Blood pressure recording apparatus and blood pressure recording method

Abstract

To accurately record a diastolic blood pressure value on the basis of Korotkoff sounds.SOLUTION: Provided is a blood pressure recording apparatus, including a cuff 20, a cuff pressure adjustment part 32, 33, and a pressure detection part 31 for detecting a cuff pressure. In a pressure reduction process, time when a waveform feature point of a beat is generated is detected for each beat of a pulse wave shown by an artery passing through a part to be measured. In the pressure reduction process, time when a waveform feature point of a beat is generated and a cuff pressure at the time are associated with each other, and sequentially stored in a memory 51 as a data pair. The cuff pressure is displayed on a display device 50. In the pressure reduction process, an observer who hears the Korotkoff sounds with a stethoscope while looking at the cuff pressures displayed on the display device 50 operates an operation part 52B to input a timing signal indicating the time at which it is determined that the generation of the Korotkoff sounds has stopped. A data pair corresponding to one beat before the data pair corresponding to the time is specified, and the cuff pressure included in the specified data pair is recorded as a corrected diastolic blood pressure value.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a blood pressure recording device, and more particularly to a blood pressure recording device that measures and records blood pressure based on Korotkoff sounds generated by an artery passing through a measurement site. The present invention also relates to a blood pressure recording method for measuring and recording blood pressure using such a blood pressure recording device.

Background Art

[0002] Conventionally, as this type of blood pressure recording device, for example, as disclosed in Non-Patent Document 1 (“UM-102 / UM-102B Aneroid Sphygmomanometer Instruction Manual”, A&D Company, Limited, Internet <URL: https: / / www.aandd.co.jp / products / medical / equipment / me-sphygmomanometer / um102 / >), instead of a traditional mercury sphygmomanometer, a manual electronic blood pressure meter equipped with a pressure indicator that electronically displays the pressure (cuff pressure) of a cuff attached to the upper arm of a subject as a bar graph along a scale is known. This electronic blood pressure meter (conventional example) has a HOLD button. When an observer (such as a doctor or a nurse) determines the systolic blood pressure or the diastolic blood pressure by auscultation during the decompression process (during blood pressure measurement) and presses the HOLD button, the pressure value at that time is displayed and held (substantially recorded) in numbers (hold function).

Prior Art Documents

Non-Patent Documents

[0003]

Non-Patent Document 1

Non-Patent Document 2

[0004] As described in Non-Patent Literature 2 (George S. Stergiou et al, “Validation of the A&D UM-101 professional hybrid device for office blood pressure measurement according to the International Protocol”, Blood Pressure Monitoring 2008, Vol. 13, No. 1, pp37-42), the above-mentioned electronic blood pressure monitor has a problem in that, when the HOLD button (mark button) is used, the blood pressure is systematically underestimated compared to the actual blood pressure, and therefore fails to meet the validation criteria. The same document suggests that the reason for this is due to the reaction time required for the observer to press the HOLD button (mark button).

[0005] Here, the inventors repeatedly conducted blood pressure measurement experiments using the hold function of the electronic blood pressure monitor described above, and found that the tendency for blood pressure to be underestimated compared to actual blood pressure was more pronounced in diastolic blood pressure than in systolic blood pressure. Specifically, the inventors used the electronic blood pressure monitor described above to simultaneously perform blood pressure measurement using the normal auscultation method and blood pressure measurement using the hold function. In blood pressure measurement using the normal auscultation method, the observer read the systolic and diastolic blood pressure based on the Korotkoff sounds heard through a stethoscope while looking at the cuff pressure displayed in real time as a bar graph on the pressure indicator (these read values ​​are called "auscultation values"). On the other hand, in blood pressure measurement using the hold function, the observer pressed the HOLD button when they determined the systolic or diastolic blood pressure based on the Korotkoff sounds heard through a stethoscope while looking at the cuff pressure displayed in real time as a bar graph on the pressure indicator, and recorded the cuff pressure at that time (these recorded values ​​are called "HOLD values"). Then, for each of the 60 measurements, the difference between the obtained HOLD value and the auscultation value (HOLD value - auscultation value) was calculated. Figure 22(A) shows a scatter plot of the obtained systolic blood pressure, with the auscultatory value on the x-axis and the difference (HOLD value - auscultatory value) on the y-axis. Figure 22(B) shows a scatter plot of the obtained diastolic blood pressure, with the auscultatory value on the x-axis and the difference (HOLD value - auscultatory value) on the y-axis. As can be seen from these figures, the average difference (HOLD value - auscultatory value) for systolic blood pressure was -1.5 mmHg. On the other hand, the average difference (HOLD value - auscultatory value) for diastolic blood pressure was -3.2 mmHg. Thus, when using the hold function of the electronic blood pressure monitor, the tendency for blood pressure to be evaluated lower than the actual blood pressure (auscultatory value) was more pronounced in diastolic blood pressure.

[0006] The reason for this is analyzed as follows. The upper panel of Figure 21 shows the changes in arterial pressure Pa and cuff pressure Pc over time. Arterial pressure Pa shows a mountain-shaped waveform that rises between the diastolic blood pressure DIA and systolic blood pressure SYS with each pulse wave, showing a peak and then falling. Cuff pressure Pc is initially pressurized by the inflation bulb to Pcmax, which is about 30 mmHg higher than the expected systolic blood pressure, and then reduced at a typical depressurization rate of 2-3 mmHg / second. When cuff pressure Pc falls below systolic blood pressure SYS, Korotkoff sounds Kc begin to be generated with each pulse, as shown in the lower panel of Figure 21, and when cuff pressure Pc falls below diastolic blood pressure DIA, the generation of Korotkoff sounds Kc stops. Here, the observer presses the HOLD button for systolic blood pressure SYS at the time when they determine that the Korotkoff sound Kc has started to be produced, that is, at time t1 when the first Korotkoff sound Kcf is heard from a state of silence (for simplicity, the observer's reaction time is omitted in the lower part of Figure 21). Therefore, the observer can press the HOLD button at a relatively correct time. On the other hand, for diastolic blood pressure DIA, the observer presses the HOLD button at the time when they first determine that the Korotkoff sound Kc has stopped being heard after being continuously heard with each beat, more specifically, at time t2 when they first determine that it has stopped being heard one beat Δt later than the time t20 when the last Korotkoff sound Kce was actually heard. Therefore, at time t2 when the observer presses the HOLD button, the cuff pressure Pc is already one beat ΔP lower than the true diastolic blood pressure DIA. This is considered to be the reason why, when using the hold function of the electronic blood pressure monitor described above, the obtained diastolic blood pressure is evaluated (recorded) as particularly low compared to the actual blood pressure (auscultatory value). This analysis was independently performed by the inventor.

[0007] Therefore, the object of this invention is to provide a blood pressure recording device configured to measure and record blood pressure based on Korotkoff sounds generated by arteries passing through the measurement site of a subject, which can accurately record diastolic blood pressure values ​​(minimum blood pressure) when an observer operates an operating unit (for example, the HOLD button mentioned above) based on Korotkoff sounds. The object of this invention is to provide a blood pressure recording method using such a blood pressure recording device, which can accurately record diastolic blood pressure values ​​(minimum blood pressure). [Means for solving the problem]

[0008] To solve the above problems, in the first phase, the blood pressure recording device of this disclosure is A blood pressure recording device configured to measure and record blood pressure based on Korotkoff sounds generated by arteries passing through the measurement site of a subject, A cuff is attached around the area to be measured, A cuff pressure adjustment unit for increasing or decreasing the cuff pressure, which is the pressure of the cuff mentioned above, During the process of reducing the cuff pressure by the cuff pressure adjustment unit described above, a pressure detection unit detects the cuff pressure, During the decompression process described above, a time detection unit detects the time at which a waveform characteristic point occurs for each beat of the pulse wave shown by the artery passing through the measured site, A first data storage unit sequentially stores in memory a data pair, associating the time at which the waveform feature point of the beat occurred or the code corresponding to that time with the cuff pressure at the time the waveform feature point of the beat occurred during the decompression process described above. Display unit and A first display processing unit performs a process to display the cuff pressure detected by the pressure detection unit on the display unit, During the decompression process described above, the system includes an operating unit configured to be operated by an observer who, while viewing the cuff pressure displayed on the display unit by the first display processing unit, listens to the Korotkoff sounds generated by the arteries passing through the area being measured using a stethoscope, The above-mentioned operating unit receives a first timing signal indicating the time when the observer determined that the Korotkoff tone had started to occur, and / or a second timing signal indicating the time when the observer determined that the Korotkoff tone had stopped to occur. During the decompression process described above, the recording processing unit identifies a data pair from a series of data pairs stored in the memory that corresponds to the time indicated by the second timing signal, and records the cuff pressure included in the identified data pair as the corrected diastolic blood pressure value. It is characterized by having the following features.

[0009] In this specification, “subject” refers to the person whose blood pressure is to be measured, typically a patient. “Observer” refers to the person who measures and records blood pressure, typically a medical professional such as a doctor or nurse.

[0010] "Korotkoff sounds" refer to the sounds produced by the arteries passing through the measurement site with each beat during the cuff pressure reduction process. "Measurement site" typically refers to the subject's upper arm.

[0011] Furthermore, the "waveform feature points" of a pulse wave refer to characteristic points within a beat that can identify the timing, such as the rising point indicating the onset of the beat, or the peak point indicating the peak (the highest point) of the beat.

[0012] Furthermore, the "code corresponding to the time" in which a waveform feature point occurs refers, for example, to a sequential number (beat number) assigned to each beat.

[0013] The term "operation unit" broadly includes means by which an observer can input a timing signal, such as a switch that is temporarily turned on when pressed, like a HOLD button in conventional examples, or a touch key that is temporarily turned on when touched.

[0014] "The data pair corresponding to the time indicated by the timing signal" refers to the data pair stored in the memory during the decompression process that was stored immediately before the time indicated by the timing signal (specifically, by the amount of time the observer took to react).

[0015] In this first phase of the blood pressure recording device, as preparation for blood pressure measurement, the cuff is fitted around the area to be measured on the subject. A stethoscope is also placed against the part of the area to be measured through which the artery passes (typically the part downstream of the cuff). In this state, the cuff pressure is increased by the cuff pressure adjustment unit, temporarily stopping the blood flow in the artery passing through the area to be measured. Then, during the cuff pressure depressurization process, the cuff pressure is detected by the pressure detection unit. Simultaneously, during the depressurization process, the time detection unit detects the time at which the waveform characteristic point of each pulse wave, as shown by the artery passing through the area to be measured, occurred. Also during the depressurization process, the first data storage unit associates the time at which the waveform characteristic point of each pulse occurred, or the code corresponding to that time, with the cuff pressure at the time the waveform characteristic point of that pulse occurred, and sequentially stores them as data pairs in the memory. Furthermore, during the decompression process, the observer, while viewing the cuff pressure displayed on the display by the first display processing unit, listens to the Korotkoff sounds generated by the arteries passing through the measured area using a stethoscope, and operates the control unit to input a second timing signal indicating at least the time when the occurrence of the Korotkoff sounds has stopped. The recording processing unit then identifies a data pair from a series of data pairs stored in the memory during the decompression process that corresponds to one beat prior to the data pair corresponding to the time indicated by the second timing signal, and the cuff pressure included in the identified data pair is recorded as a corrected diastolic blood pressure value.

[0016] Thus, in the blood pressure recording device of this first aspect, the recording processing unit identifies, among a series of data pairs stored in the memory during the decompression process, the data pair corresponding to the time indicated by the second timing signal and the data pair corresponding to one beat before that data pair. The cuff pressure included in the identified data pair is recorded as the corrected diastolic blood pressure value. According to the analysis of the present inventor described above, the corrected diastolic blood pressure value does not represent the time when the observer can first determine that the Korotkoff sound has stopped being heard continuously for each beat, but rather represents the cuff pressure corresponding to the time when the last Korotkoff sound was actually heard. Therefore, according to this blood pressure recording device, the phenomenon in which the minimum blood pressure is evaluated about one beat lower can be corrected.

[0017] Also, as described in Non-Patent Document 2, it is considered that it takes a certain reaction time from when the observer determines that the generation of the Korotkoff sound has stopped until the operation unit is operated to input the second timing signal. However, in the blood pressure recording device of this first aspect, during the decompression process, the first data storage unit sequentially stores the data pairs (that is, the time when the waveform feature point of the beat occurred or the code corresponding to that time, and the cuff pressure at the time when the waveform feature point of the beat occurred) in the memory without being affected by such a reaction time. Therefore, the data pair identified by the recording processing unit is stored without being affected by the observer's reaction time. Also, it is assumed that the observer's reaction time usually does not exceed one beat. As a result, the corrected diastolic blood pressure value is practically not affected by the observer's reaction time.

[0018] Note that there may be a slight deviation (time interval) between the time when the waveform feature point of each beat occurs and the time when the Korotkoff sound of that beat occurs. However, usually, the deviation does not reach half a beat, so the deviation does not substantially reduce the accuracy of blood pressure measurement (recording).

[0019] As described above, according to the blood pressure recording device of this first aspect, the diastolic blood pressure value can be recorded with higher accuracy compared to the conventional example.

[0020] In a blood pressure recording device according to an embodiment, the recording processing unit specifies a data pair corresponding to the time indicated by the first timing signal among the series of data pairs stored in the memory, and records the cuff pressure included in the specified data pair as the systolic blood pressure value. It is characterized by this.

[0021] According to the analysis of the present inventor described above, the time indicated by the first timing signal corresponds to the time when the observer determines that the Korotkoff sound has started to occur, that is, the time when the first Korotkoff sound is heard from the silent state. Here, as described in Non-Patent Document 2, it is considered that a slight reaction time is required from when the observer determines the above-mentioned Korotkoff sound It began to occur. until the operation unit is operated and the first timing signal is input. However, as described above, the data pair specified by the recording processing unit is stored without being affected by the reaction time of the observer. Also, the reaction time of the observer is assumed to usually not exceed one beat per minute. As a result, in the blood pressure recording device of this embodiment, the recorded systolic blood pressure value is practically not affected by the reaction time of the observer. Therefore, according to the blood pressure recording device of this embodiment, the systolic blood pressure value can be accurately recorded.

[0022] In a blood pressure recording device according to an embodiment, the recording processing unit determines whether the operation of the operation unit is the first time or the second time or later during the decompression process, and uses the time when the first operation is performed as the time indicated by the first timing signal to record the systolic blood pressure value, and also uses the time when the second and subsequent operations are performed as the time indicated by the second timing signal to record the corrected diastolic blood pressure value. It is characterized by this.

[0023] In a typical case, it is assumed that the observer intends to record the systolic blood pressure value when operating the control unit for the first time, and the diastolic blood pressure value (corrected diastolic blood pressure value in this invention) when operating the control unit for the second time. Therefore, in this embodiment of the blood pressure recording device, the recording processing unit determines whether the operation of the control unit is the first or second or subsequent operation during the decompression process, and uses the time when the first operation was performed as the time indicated by the first timing signal to record the systolic blood pressure value. Furthermore, the time when the second or subsequent operation was performed is used as the time indicated by the second timing signal to record the corrected diastolic blood pressure value. As a result, with this embodiment of the blood pressure recording device, both the systolic blood pressure value and the corrected diastolic blood pressure value can be recorded quickly. The observer can end the blood pressure measurement as soon as the corrected diastolic blood pressure value is recorded, even if the decompression process is still in progress.

[0024] The phrase "from the second time onward" is intended to accommodate the possibility that the control unit may be operated three or more times during the decompression process, such as when the subject is exhibiting arrhythmia or is pregnant.

[0025] In one embodiment of the blood pressure recording device, The above operating unit includes a first switch for receiving instructions to record the systolic blood pressure value and a second switch for receiving instructions to record the diastolic blood pressure value. The recording processing unit records the systolic blood pressure value during the decompression process, using the time when the first switch is operated as the time indicated by the first timing signal, and records the corrected diastolic blood pressure value, using the time when the second switch is operated as the time indicated by the second timing signal. It is characterized by the following:

[0026] In this embodiment of the blood pressure recording device, during the decompression process, the observer operates the first switch to record the systolic blood pressure value at the time they determine that the Korotkoff sounds have begun to occur. The recording processing unit then uses the time the first switch was operated during the decompression process as the time indicated by the first timing signal and records the systolic blood pressure value. Furthermore, during the decompression process, the observer operates the second switch to record the diastolic blood pressure value at the time they determine that the Korotkoff sounds have stopped occurring. The recording processing unit then uses the time the second switch was operated during the decompression process as the time indicated by the second timing signal and records the corrected diastolic blood pressure value. Thus, with this embodiment of the blood pressure recording device, both the systolic blood pressure value and the corrected diastolic blood pressure value can be quickly recorded according to the observer's intention (whether to record the systolic blood pressure value or the diastolic blood pressure value). Furthermore, the observer can terminate blood pressure measurement as soon as the corrected diastolic blood pressure value is recorded, even if the decompression process is still in progress. Moreover, since the recording processing unit does not need to determine whether the operation of the control unit is the first or second time during the decompression process, the processing by the recording processing unit is simplified.

[0027] In one embodiment of the blood pressure recording device, Each time the above-mentioned operating unit is operated during the decompression process, a data pair identification unit identifies the data pair corresponding to the time of operation and maintains information indicating each identified data pair. A second display processing unit, which, from a series of data pairs stored in the memory during the depressurization process described above, displays the cuff pressures included in the data pairs identified by the data pair identification unit as options on the display unit, The above display unit includes a selection operation unit for selecting the option that the observer considers to correspond to the diastolic blood pressure value from among the above options, After the decompression process is completed, the recording processing unit records the corrected diastolic blood pressure value using the data pair containing the cuff pressure represented by the option selected by the selection operation unit from the series of data pairs stored in the memory during the decompression process, as the data pair corresponding to the time indicated by the second timing signal. It is characterized by the following:

[0028] In this specification, "data pair corresponding to the time of operation" refers to the data pair stored in the memory during the decompression process that was stored immediately before the time the operation was performed (specifically, by the time of the observer's reaction).

[0029] Furthermore, "after the decompression process is completed" refers, for example, to the period after the cuff pressure reaches a predetermined pressure (e.g., 30 mmHg) that is not normally expected for diastolic blood pressure.

[0030] Furthermore, the term "selection operation unit" broadly includes means for selecting options displayed on the display unit (for example, marks representing pressure values ​​based on their position along a scale).

[0031] In this embodiment of the blood pressure recording device, the data pair identification unit identifies the data pair corresponding to the time of operation each time the operation unit is operated during the decompression process, and maintains information indicating each identified data pair. The second display processing unit displays the cuff pressures included in the data pairs identified by the data pair identification unit on the display unit as options (for example, marks indicating pressure values ​​by position along a scale) from a series of data pairs stored in the memory during the decompression process. The observer uses the selection operation unit to select the option displayed on the display unit that the observer considers to correspond to the diastolic blood pressure. Then, after the decompression process is completed, the recording processing unit uses the data pair containing the cuff pressure represented by the option selected by the selection operation unit from the series of data pairs stored in the memory during the decompression process as the data pair corresponding to the time indicated by the second timing signal, and records the corrected diastolic blood pressure value. As a result, according to this embodiment of the blood pressure recording device, the corrected diastolic blood pressure value can be recorded according to the observer's selection (selection of which option corresponds to diastolic blood pressure).

[0032] In one embodiment of the blood pressure recording device, During the depressurization process described above, each time the operating unit is operated, the data pair identification unit identifies the data pair corresponding to the time of operation and maintains information indicating each identified data pair. Equipped with , After the decompression process is completed, the recording processing unit uses the data pair identified by the data pair identification unit that corresponds to the time the last operation was performed as the data pair that corresponds to the time indicated by the second timing signal, and records the corrected diastolic blood pressure value. It is characterized by the following:

[0033] In this embodiment of the blood pressure recording device, during the decompression process, the data pair identification unit identifies the data pair corresponding to the time of operation each time the operation unit is operated, and maintains information indicating each identified data pair. After the decompression process is completed, the recording processing unit uses the data pair corresponding to the time of the last operation among the data pairs identified by the data pair identification unit as the data pair corresponding to the time indicated by the second timing signal, and records the corrected diastolic blood pressure value. This embodiment of the blood pressure recording device simplifies the processing performed by the recording processing unit.

[0034] In one embodiment of the blood pressure recording device, further, A third display processing unit causes the above-mentioned corrected diastolic blood pressure value to be displayed on the above-mentioned display unit as a digital value and / or as a mark indicating the pressure value by position along the scale. It is characterized by having the following features.

[0035] In this embodiment of the blood pressure recording device, the third display processing unit causes the corrected diastolic blood pressure value to be displayed on the display as a digital value and / or as a mark indicating the pressure value by position along the scale. Therefore, the observer can easily recognize the corrected diastolic blood pressure value by looking at the display.

[0036] In one embodiment of the blood pressure recording device, The first data storage unit described above begins to sequentially store the data pairs in the memory during the depressurization process, starting with the data pair corresponding to the time when the first operation was performed by the operation unit. It is characterized by the following:

[0037] In this embodiment of the blood pressure recording device, the memory resources can be saved compared to a case where the first data storage unit begins to sequentially store the data pairs in the memory at the same time as the start of the decompression process.

[0038] In the second phase, the blood pressure recording method of this disclosure is A blood pressure recording method comprising measuring and recording the blood pressure at a measurement site of a subject using a blood pressure recording device in the first phase, The cuff is placed around the area to be measured, and the stethoscope is placed against the part of the area to be measured through which the artery passes. After the cuff pressure is increased by the cuff pressure adjustment unit to temporarily stop blood flow in the artery passing through the measurement site, during the cuff pressure depressurization process, The above-mentioned pressure detection unit detects the cuff pressure, The above time detection unit detects a signal representing the time at which the waveform characteristic point of each pulse occurred in the pulse wave shown by the artery passing through the measured site. The first data storage unit associates the time at which the waveform feature point of the beat occurred or the code corresponding to that time with the cuff pressure at the time the waveform feature point of that beat occurred, and sequentially stores them as data pairs in the memory. While observing the cuff pressure displayed on the display unit by the first display processing unit, the observer, who has heard the Korotkoff sounds generated by the arteries passing through the measured area using a stethoscope, operates the control unit to input a second timing signal indicating at least the time when the observer determined that the generation of the Korotkoff sounds had stopped. During or after the decompression process, the recording processing unit identifies a data pair from a series of data pairs stored in the memory during the decompression process that corresponds to one beat prior to the data pair corresponding to the time indicated by the second timing signal, and records the cuff pressure included in the identified data pair as the corrected diastolic blood pressure value. It is characterized by the following:

[0039] This second phase of blood pressure recording method allows for more accurate recording of diastolic blood pressure values ​​compared to conventional methods.

[0040] In the third phase, the blood pressure recording device of this disclosure, A blood pressure recording device configured to measure and record blood pressure based on Korotkoff sounds generated by arteries passing through the measurement site of a subject, A cuff is attached around the area to be measured, A cuff pressure adjustment unit for increasing or decreasing the cuff pressure, which is the pressure of the cuff mentioned above, During the process of reducing the cuff pressure by the cuff pressure adjustment unit described above, a pressure detection unit detects the cuff pressure, During the decompression process described above, a microphone is used to convert the sound generated by the arteries passing through the measured site into an electrical signal, which is an audio signal, and output it. A Korotkoff tone signal detection unit detects a Korotkoff tone signal from the sound signal output by the microphone, A second data storage unit sequentially stores in memory as a data pair the time at which the Korotkoff tone signal was detected or the code corresponding to that time, and the cuff pressure at the time the Korotkoff tone signal was detected, during the decompression process described above. Display unit and The cuff pressure detected by the pressure detection unit is displayed on the display unit. to A first display processing unit that performs the processing to display, During the decompression process described above, the system includes an operating unit configured to be operated by an observer who, while viewing the cuff pressure displayed on the display unit by the first display processing unit, hears Korotkoff sounds generated by arteries passing through the area being measured using a stethoscope, or hears Korotkoff sounds indicated by the Korotkoff sound signal using an electroacoustic conversion device, The above-mentioned operating unit receives a first timing signal indicating the time when the observer determined that the Korotkoff tone had started to occur, and / or a second timing signal indicating the time when the observer determined that the Korotkoff tone had stopped to occur. During the decompression process described above, the recording processing unit identifies the last data pair stored in the memory, working backward from the time indicated by the second timing signal, and records the cuff pressure included in that identified data pair as the corrected diastolic blood pressure value. It is characterized by having the following features.

[0041] In this specification, "Korotkoff tone signal" refers to a pulsed electrical signal that represents a Korotkoff tone. Furthermore, "electrical sound conversion device" refers to a device that converts an electrical signal into sound, such as a speaker, headphones, or earphones.

[0042] In this third phase of the blood pressure recording device, as preparation for blood pressure measurement, the cuff is fitted around the area to be measured on the subject. The microphone is positioned to acquire the sound generated by the arteries passing through the area to be measured. Alternatively, in addition to the placement of the microphone, a stethoscope is placed against the part of the area to be measured through which the arteries pass (typically, the part downstream of the cuff). In this state, the cuff pressure is increased by the cuff pressure adjustment unit, temporarily stopping the blood flow in the arteries passing through the area to be measured. Then, during the cuff pressure depressurization process, the cuff pressure is detected by the pressure detection unit. Simultaneously, during the depressurization process, the Korotkoff sound detection unit detects a Korotkoff sound signal from the sound signal output by the microphone. Alternatively, in addition to the above, the sound generated by the arteries passing through the area to be measured is converted into an electrical signal, which is an audio signal, and output by the microphone. Furthermore, during the decompression process, the second data storage unit associates the time when the Korotkoff sound signal was detected or a code corresponding to that time with the cuff pressure at the time the Korotkoff sound signal was detected, and stores them sequentially in the memory as a data pair. In addition, during the decompression process, while observing the cuff pressure displayed on the display by the first display processing unit, an observer who has heard the Korotkoff sound generated by the artery passing through the measured site using a stethoscope, or who has heard the Korotkoff sound indicated by the Korotkoff sound signal using the electroacoustic conversion device, inputs a second timing signal via the operation unit indicating at least the time when they determined that the generation of the Korotkoff sound had stopped. Then, the recording processing unit identifies the last data pair stored in the memory during the decompression process, working backward from the time indicated by the second timing signal, and records the cuff pressure included in that identified data pair as a corrected diastolic blood pressure value.

[0043] Thus, in this third phase of the blood pressure recording device, the recording processing unit identifies the last data pair stored in the memory during the decompression process, working backward from the time indicated by the second timing signal. The cuff pressure included in this identified data pair is then recorded as the corrected diastolic blood pressure value. According to the inventor's analysis described above, the corrected diastolic blood pressure value represents the cuff pressure corresponding to the time the last Korotkoff tone was actually heard, not the time when the observer first determined that the Korotkoff tone had stopped being heard after being heard continuously with each beat. Therefore, this blood pressure recording device can correct the phenomenon in which the lowest blood pressure is underestimated by about one beat.

[0044] Furthermore, as described in Non-Patent Document 2 (George S. Stergiou et al, “Validation of the A&D UM-101 professional hybrid device for office blood pressure measurement according to the International Protocol”, Blood Pressure Monitoring 2008, Vol. 13, No. 1, pp37-42), it is thought that a slight reaction time is required from the time the observer determines that the Korotkoff sound has stopped until they operate the control unit to input the second timing signal. However, in this third phase of the blood pressure recording device, during the decompression process, the second data storage unit sequentially stores the data pairs (i.e., the time when the Korotkoff sound signal was detected or the code corresponding to that time, and the cuff pressure at the time the Korotkoff sound signal was detected) in the memory without being affected by such reaction time. Therefore, the data pairs identified by the recording processing unit are stored without being affected by the observer's reaction time. As a result, the corrected diastolic blood pressure value is practically unaffected by the observer's reaction time.

[0045] Based on the above, this third-phase blood pressure recording device can record diastolic blood pressure values ​​with greater accuracy compared to conventional examples.

[0046] In one embodiment of the blood pressure recording device, At the location of the subject having the above-mentioned measurement site, The above-mentioned cuff, the above-mentioned cuff pressure adjustment unit, the above-mentioned pressure detection unit, the above-mentioned microphone, and the above-mentioned Korotkoff sound signal detection unit are arranged, During the depressurization process described above, a transmission unit is provided that sequentially transmits the Korotkoff sound signal detected by the Korotkoff sound signal detection unit and the cuff pressure signal representing the cuff pressure detected by the pressure detection unit as measurement data, in a time-synchronized manner. At the location of the observer, which is located some distance from the location of the subject, A receiving unit is provided to receive the above measurement data, The second data storage unit, the memory, the display unit, the sound conversion device, the first display processing unit, the operation unit, and the recording processing unit are arranged as follows: During the decompression process described above, based on the received measurement data, The first display processing unit described above causes the cuff pressure to be displayed on the display unit. The second data storage unit associates the time when the Korotkoff tone signal was detected or a code corresponding to that time with the cuff pressure at the time the Korotkoff tone signal was detected, and sequentially stores them as data pairs in the memory. During the depressurization process described above, while observing the cuff pressure displayed on the display unit by the first display processing unit, the observer hears the Korotkoff tone indicated by the Korotkoff tone signal via the electro-sound conversion device and operates the control unit to input at least the second timing signal. It is characterized by the following:

[0047] In this specification, “subject location” typically refers to the location of the residence where the patient, acting as a subject, lives. Similarly, “observer location” typically refers to the location of the medical institution where the physician or nurse, acting as the observer, is employed.

[0048] In this embodiment of the blood pressure recording device, the cuff is attached to the subject's body part to be measured at the subject's location. The microphone is positioned to acquire sound generated by the arteries passing through the body part to be measured. In this state, the cuff pressure is increased by the cuff pressure adjustment unit, temporarily stopping blood flow in the arteries passing through the body part to be measured. During the cuff pressure depressurization process, the cuff pressure is detected by the pressure detection unit. Simultaneously, during the depressurization process, the sound signal output by the microphone and the cuff pressure signal representing the cuff pressure detected by the pressure detection unit are synchronized in time and transmitted sequentially as measurement data by the transmission unit.

[0049] Meanwhile, the measurement data is received by the receiving unit at the observer's location, which is located some distance from the subject's location. During the decompression process, based on the received measurement data, the first display processing unit displays the cuff pressure on the display. to The display is shown. Also, in synchronization with the display of the cuff pressure, the Korotkoff sound signal detection unit detects the Korotkoff sound signal from the sound signal included in the measurement data. Furthermore, the second data storage unit associates the time when the Korotkoff sound signal was detected or the code corresponding to that time with the cuff pressure at the time the Korotkoff sound signal was detected, and stores them sequentially in the memory as data pairs. In addition, during the depressurization process, the first display processing unit controls the display. to While observing the cuff pressure displayed above, an observer who hears the Korotkoff sound indicated by the Korotkoff sound signal via the electroacoustic conversion device operates the control unit to input at least the second timing signal. The recording processing unit then identifies the last data pair stored in the memory during the decompression process, working backward from the time indicated by the second timing signal, and records the cuff pressure included in that identified data pair as the corrected diastolic blood pressure value.

[0050] According to this embodiment of the blood pressure recording device, diastolic blood pressure values ​​can be recorded with greater accuracy compared to conventional examples. Moreover, even when the location of the subject (for example, the location of the residence where the patient as the subject lives) and the location of the observer (for example, the location of the medical institution where the doctor or nurse as the observer works) are far apart, the corrected diastolic blood pressure values ​​can be recorded by the exchange of measurement data between the transmitting unit and the receiving unit.

[0051] In the fourth phase, the blood pressure recording method of this disclosure is A blood pressure recording method comprising measuring and recording the blood pressure at a measurement site of a subject using a third-phase blood pressure recording device, The cuff is attached around the area to be measured, The microphone is positioned to acquire the sound generated by the artery passing through the area to be measured, or, in addition to positioning the microphone, the stethoscope is placed in contact with the part of the area to be measured through which the artery passes. After the cuff pressure is increased by the cuff pressure adjustment unit to temporarily stop blood flow in the artery passing through the measurement site, during the cuff pressure depressurization process, The above-mentioned pressure detection unit detects the cuff pressure, The above microphone converts the sound generated by the artery passing through the measured area into the above sound signal and outputs it. The Korotkov tone signal detection unit detects the Korotkov tone signal from the sound signal output by the microphone. The second data storage unit associates the time when the Korotkoff tone signal was detected or the code corresponding to that time with the cuff pressure at the time the Korotkoff tone signal was detected, and sequentially stores them as data pairs in the memory. The display unit is operated by the first display processing unit described above. toWhile observing the cuff pressure displayed above, an observer who has heard the Korotkoff sounds generated by the arteries passing through the measured area using the stethoscope, or who has heard the Korotkoff sounds indicated by the Korotkoff sound signal using the electroacoustic conversion device, operates the control unit to input a second timing signal indicating at least the time when the generation of the Korotkoff sounds has stopped. During or after the decompression process, the recording processing unit identifies the last data pair stored in the memory during the decompression process, working backward from the time indicated by the second timing signal, and records the cuff pressure included in the identified data pair as the corrected diastolic blood pressure value. It is characterized by the following:

[0052] This fourth phase of blood pressure recording method allows for more accurate recording of diastolic blood pressure values ​​compared to conventional methods.

[0053] In one embodiment of the blood pressure recording device, The first display processing unit described above is configured to display the cuff pressure detected by the pressure detection unit as a bar graph along a scale on the display unit. A blood pressure recording device characterized by the following features.

[0054] According to this embodiment of the blood pressure recording device, the observer determines that the above-mentioned Korotkoff sounds have begun to occur, and / or the above-mentioned Korotkoff sounds of The determination that the occurrence has stopped can be made with the same ease as when using a traditional mercury sphygmomanometer. Therefore, it can be said that it is highly convenient for observers who are accustomed to using traditional mercury sphygmomanometers. [Effects of the Invention]

[0055] As is clear from the above, the blood pressure recording device and blood pressure recording method of this disclosure allow for accurate recording of diastolic blood pressure (minimum blood pressure) when an observer operates the control unit based on Korotkoff sounds. [Brief explanation of the drawing]

[0056] [Figure 1] This figure shows the block configuration of a blood pressure monitor as a first embodiment of the blood pressure recording device of this invention. [Figure 2] This figure illustrates an example of how blood pressure is measured using the blood pressure monitor described above. [Figure 3] This figure shows a flowchart of a blood pressure recording method in one embodiment using the blood pressure monitor shown in Figure 1. [Figure 4] Figure 3 illustrates the blood pressure recording method flow chart, showing how to measure and record systolic and diastolic blood pressure values. [Figure 5] Figure 5(A) is a scatter plot showing the systolic blood pressure (maximum blood pressure) recorded using the blood pressure recording method flow shown in Figure 3, with the auscultatory value on the horizontal axis and the difference (HOLD value - auscultatory value) on the vertical axis. Figure 5(B) is a scatter plot showing the diastolic blood pressure (minimum blood pressure) recorded using the blood pressure recording method flow shown in Figure 3, with the auscultatory value on the horizontal axis and the difference (HOLD value - auscultatory value) on the vertical axis. [Figure 6] This figure shows the block configuration of a blood pressure monitor as a second embodiment of the blood pressure recording device of this invention. [Figure 7] This figure shows a flowchart of a blood pressure recording method in one embodiment using the blood pressure monitor shown in Figure 6. [Figure 8] This figure shows the block configuration of a blood pressure monitor as a third embodiment of the blood pressure recording device of this invention. [Figure 9] This figure shows a flowchart of a blood pressure recording method according to one embodiment using the blood pressure monitor shown in Figure 8. [Figure 10] This diagram illustrates how to select the cuff pressure displayed as an option on the indicator after the cuff pressure reduction process is complete. [Figure 11] Figure 9 illustrates the data set stored in memory according to the blood pressure recording method flow chart. [Figure 12] This figure shows a modified flow chart of the blood pressure recording method shown in Figure 9. [Figure 13] This figure shows the block configuration of a blood pressure monitor as a fourth embodiment of the blood pressure recording device of this invention. [Figure 14] This figure shows a flowchart of a blood pressure recording method in one embodiment using the blood pressure monitor shown in Figure 13. [Figure 15] Figure 14 illustrates the blood pressure recording method flow chart, showing how to measure and record systolic and diastolic blood pressure values. [Figure 16] This figure shows the block configuration of a modified blood pressure monitor, which is a modified version of the blood pressure monitor shown in Figure 13. [Figure 17] This figure shows the block configuration of a blood pressure measurement system as a fifth embodiment of the blood pressure recording device of this invention. [Figure 18] This figure shows a portion (first half) of the flow chart of a blood pressure recording method in one embodiment using the blood pressure measurement system shown in Figure 17. [Figure 19] This figure shows the remaining portion (second half) of the flow chart for a blood pressure recording method in one embodiment using the blood pressure measurement system shown in Figure 17. [Figure 20] Figures 20(A), 20(B), and 20(C) show possible variations of the display unit that constitutes each blood pressure monitor (and blood pressure measurement system). [Figure 21] This diagram illustrates how to record systolic and diastolic blood pressure using the hold function of a conventional electronic blood pressure monitor. [Figure 22] Figure 22(A) is a scatter plot showing the systolic blood pressure recorded by the hold function of a conventional electronic blood pressure monitor, with the auscultatory value on the horizontal axis and the difference (HOLD value - auscultatory value) on the vertical axis. Figure 22(B) is a scatter plot showing the diastolic blood pressure recorded by the hold function of a conventional electronic blood pressure monitor, with the auscultatory value on the horizontal axis and the difference (HOLD value - auscultatory value) on the vertical axis. [Modes for carrying out the invention]

[0057] Hereinafter, embodiments of this invention will be described in detail with reference to the drawings.

[0058] (First Embodiment) Figure 1 shows the block configuration of a blood pressure monitor 1A as a first embodiment of the blood pressure recording device of the present invention. Figure 2 shows how an observer (in this example, a doctor) 80 measures the blood pressure of a subject (in this example, a patient) 90 at the upper arm 91, which is the site to be measured, using the blood pressure monitor 1A. The blood pressure monitor 1A is configured to measure and record blood pressure based on the Korotkoff sound Kc generated by the arteries passing through the upper arm 91 of the subject 90.

[0059] As shown in Figure 2, the blood pressure monitor 1A comprises, broadly speaking, a main body 10 including a display unit 50, a cuff 20 that is worn around the upper arm 91 of the subject 90, and a manual pump (air inflation bulb) 32 and a manual valve 33 as pressure adjustment units.

[0060] The cuff 20 is a common type used for measuring blood pressure in the upper arm 91 and contains an air bladder (not shown) for pressurizing the upper arm 91. The main body 10 and the cuff 20 are connected by a flexible air pipe 38a. The cuff 20 is also connected to the manual pump 32 and manual valve 33 by a flexible air pipe 38b. The manual pump 32 and manual valve 33 are also common types used for measuring blood pressure.

[0061] As shown in Figure 1, the main unit 10 is equipped with a control unit 110, a display unit 50, an operation unit 52, a memory 51, a power supply unit 53, a pressure sensor 31 as a pressure detection unit, and an A / D conversion circuit 310. In this example, an air pipe 38a is connected to the pressure sensor 31 in a fluid-flowable manner. In this example, the air pipe 38a and the air pipe 38b connected to the manual pump 32 and manual valve 33 merge to form a single air pipe 38, which is connected to the cuff 20 in a fluid-flowable manner.

[0062] In this example, the display unit 50, as shown in Figure 2, consists of an LCD (Liquid Crystal Display) mounted on the rear of the main unit 10, and displays predetermined information according to control signals from the control unit 110. In this example, the display unit 50 is designed to mimic a traditional mercury sphygmomanometer, displaying a vertically aligned scale 50a and a bar graph 50b that expands and contracts along the scale 50a as an image, to display the pressure of the cuff 20 during blood pressure measurement (referred to as "cuff pressure Pc"). In addition, the display unit 50 may also digitally display the cuff pressure Pc during measurement and / or the obtained blood pressure value. The display unit 50 may consist of an organic EL (Electro Luminescence) display or may include an LED (Light Emitting Diode).

[0063] As shown in Figure 1, the operation unit 52 in this example includes a power button 52A and a HOLD button 52B, and inputs signals to the control unit 110 in response to the operation of the user, the observer 80. For ease of operation, as shown in Figure 2, the power button 52A and the HOLD button 52B are located on the top surface of the main unit 10. Specifically, the power button 52A in this example is a latch-type (self-holding type) switch, which remains in the ON state when pressed once and turns OFF when pressed again. As a result, pressing the power button 52A once turns on the power of the blood pressure monitor 1A, and pressing the power button 52A again turns off the power of the blood pressure monitor 1A. On the other hand, the HOLD button 52B in this example is a momentary-type (self-resetting type) switch, which remains ON only while pressed down and returns to the OFF state when released. As will be explained in more detail later, the HOLD button 52B is used by an observer 80 who, while viewing the cuff pressure Pc displayed in real time as a bar graph 50b on the display unit 50, hears Korotkoff sounds Kc emanating from the artery passing through the upper arm 91 using a stethoscope 89, and presses the button to input a timing signal (referred to as the "first timing signal") indicating the time when the observer determines that the Korotkoff sounds Kc have started to be produced, and / or inputs a timing signal (referred to as the "second timing signal") indicating the time when the observer determines that the Korotkoff sounds Kc have stopped to be produced.

[0064] The memory 51 shown in Figure 1 stores program data for controlling the blood pressure monitor 1A, setting data for configuring various functions of the blood pressure monitor 1A, and data from blood pressure measurement and blood pressure measurement results. The memory 51 is also used as work memory when the program is executed.

[0065] The control unit 110 includes a CPU (Central Processing Unit) as a processor and controls the operation of the entire blood pressure monitor 1A. Specifically, the control unit 110 performs control to measure and record blood pressure according to a program for controlling the blood pressure monitor 1A stored in the memory 51. The specific method of measuring and recording blood pressure will be described later.

[0066] In this example, the pressure sensor 31 is a piezoresistive pressure sensor that converts the change in electrical resistance due to the piezoresistive effect caused by the pressure (cuff pressure Pc) of the cuff 20 received through the air pipes 38 and 38a into a voltage. The A / D conversion circuit 310 converts the voltage from the pressure sensor 31 from an analog value to a digital value and transmits it to the control unit 110. The control unit 110 determines the cuff pressure Pc according to that voltage.

[0067] As described above, the manual pump 32 and manual valve 33 are common types used in manual blood pressure measurement. When the manual pump 32 is operated with the manual valve 33 closed, air is supplied from the manual pump 32 to the cuff 20 via the air pipes 38b and 38, and the cuff pressure Pc is pressurized. When the manual valve 33 is opened, air is exhausted from the cuff 20 into the atmosphere via the air pipes 38 and 38b and the manual valve 33, and the cuff pressure Pc is reduced.

[0068] The power supply unit 53 supplies or cuts off power to the control unit 110, display unit 50, memory 51, pressure sensor 31, and other parts of the main unit 10 in accordance with the ON / OFF status of the power button 52A.

[0069] Figure 3 shows a flow chart of a blood pressure recording method in one embodiment in which an observer 80 measures and records the blood pressure of a subject 90's upper arm 91 using a blood pressure monitor 1A. In Figure 3 (and in Figures 7, 9, 12, 14, and 19 described later), for ease of understanding, the processing and decisions made by the control unit 110 within the main unit 10 are outlined with solid lines, and manual operations and manual inputs by the observer 80 are outlined with dashed lines, placed next to the solid line flow chart.

[0070] In preparation for blood pressure measurement, in this example, observer 80 places the cuff 20 around the upper arm 91 of subject 90 and places the stethoscope 89 against the portion of subject 90's upper arm 91 through which the artery passes (the portion corresponding to the downstream side of the cuff 20). The manual valve 33 is also assumed to be open.

[0071] In this state, when the observer 80 turns on the power button 52A of the blood pressure monitor 1A, the control unit 110 in the main unit 10 initializes the processing memory area and initializes the pressure sensor 31 (step S101 in Figure 3). Specifically, with the manual valve 33 open, the pressure sensor 31 is adjusted to 0 mmHg (setting atmospheric pressure to 0 mmHg).

[0072] Next, in step S102, the control unit 110 acts as the first display processing unit and starts the process of displaying the current cuff pressure Pc detected by the pressure sensor 31 on the display unit 50 as a bar graph 50b along the scale 50a in real time. Initially, 0 mmHg is displayed.

[0073] In this state, the observer 80 closes the manual valve 33 (step S103) and uses the manual pump 32 to pressurize the cuff pressure Pc to Pcmax, which is approximately 30 mmHg higher than the expected systolic blood pressure (steps S104, S105). This temporarily stops the blood flow through the artery in the upper arm 91. Next, in step S106, the observer 80 gradually opens the manual valve 33 and begins to reduce the cuff pressure Pc at a typical depressurization rate of 2-3 mmHg / second. As shown in step S107, the control unit 110 waits for the depressurization to begin, displaying the current cuff pressure Pc on the display unit 50. Here, whether or not depressurization has begun can be determined by the control unit 110, for example, calculating the first derivative coefficient (dPc / dt) of the cuff pressure Pc with respect to time t detected by the pressure sensor 31, and checking whether the first derivative coefficient (dPc / dt) is negative or not.

[0074] When depressurization begins (Yes in step S107), the control unit 110 performs the processes in steps S108 to S114 during this depressurization process.

[0075] Here, the upper panel of Figure 4 illustrates the changes in arterial pressure Pa and cuff pressure Pc over time. In this example, the arterial pressure Pa shows a bell-shaped waveform, rising between the diastolic blood pressure DIA and systolic blood pressure SYS with a rising point Pf for each pulse wave (in this example, the period is T), then falling with a peak point Pp. As described above, during the pressurization process, the cuff pressure Pc is initially pressurized to Pcmax, approximately 30 mmHg higher than the expected systolic blood pressure, and then, in the decompression process, is reduced at a rate of 2-3 mmHg / second in this example. When the cuff pressure Pc falls below the systolic blood pressure SYS, Korotkoff sounds Kc begin to occur with each pulse, as shown in the middle panel of Figure 4, and when the cuff pressure Pc falls below the diastolic blood pressure DIA, the generation of Korotkoff sounds Kc stops. In this decompression process, Kcf indicates the first Korotkoff sound, and Kce indicates the last Korotkoff sound.

[0076] During this decompression process, the control unit 110 acts as a time detection unit and, first in step S108 of Figure 3, begins to determine the time at which the rising point Pf (see upper part of Figure 4), which is a waveform characteristic point of the pulse wave, occurs for each beat. The rising point Pf of the beat is determined by the control unit 110 extracting the fluctuation component (let's call it Pm) of the cuff pressure Pc detected by the pressure sensor 31, for example, and calculating the first derivative coefficient (dPm / dt) and second derivative coefficient (d) of this fluctuation component Pm with respect to time t. 2 PM / DT 2 ) is calculated, and the sign of its first derivative (dPm / dt) changes from negative to positive, as does the second derivative (d 2 PM / DT 2 This can be determined by detecting the point where ) becomes zero.

[0077] Furthermore, instead of using the rising point Pf, which indicates the onset of the beat, as the "waveform feature point" of the pulse wave, the peak point Pp, which indicates the peak (the highest point of the mountain) of the beat, may be used.

[0078] In parallel with this process, in step S109 of Figure 3, the control unit 110 acts as a first data storage unit and starts the process of associating the beat number N, which is a code corresponding to the time when the rise point Pf of a beat occurred, with the cuff pressure Pc at the time when the rise point Pf of a beat occurred, and sequentially storing them as data pairs in the memory 51. In this example, as shown in the lower part of Figure 4, a series of data pairs obtained during this decompression process (referred to as a "data set") DS1 is stored, with the data pair of beat number N=1 and cuff pressure Pc=141 (mmHg) being stored next, the data pair of beat number N=2 and cuff pressure Pc=138 (mmHg) being stored next, and so on, until finally the data pair of beat number N=18 and cuff pressure Pc=93 (mmHg) being stored. Since this process is performed without the operation of the observer 80, this data set DS1 is stored without being affected by the reaction time (described later) when the observer 80 presses the HOLD button 52B.

[0079] Alternatively, the time at which the beat rise point Pf occurs and the cuff pressure Pc at that time may be directly associated and sequentially stored as a data pair in memory 51. However, by using the beat number N as described above, the resources of memory 51 can be saved.

[0080] Furthermore, instead of the rising edge Pf of the beat, the peak point Pp may be used as the waveform feature point of the beat. The peak point Pp of the beat is obtained by the control unit 110, for example, by extracting the fluctuation component (let's call it Pm) from the cuff pressure Pc detected by the pressure sensor 31 through a filter, and then calculating the first derivative coefficient (dPm / dt) and second derivative coefficient (d) of this fluctuation component Pm with respect to time t. 2 PM / DT 2 ) is calculated, and the sign of its first derivative (dPm / dt) changes from positive to negative, as does the second derivative (d 2 PM / DT 2 This can be determined by detecting the point where ) becomes zero.

[0081] During the decompression process described above, while steps S108 and S109 in Figure 3 are being performed, in step S110, the control unit 110 determines whether or not the HOLD button 52B has been pressed. If the HOLD button 52B has not been pressed (No in step S110), the control unit 110 continues the process from steps S108 to S110 as long as the current cuff pressure Pc is above a predetermined pressure (30 mmHg in this example) (No in step S115). Note that 30 mmHg is a pressure lower than the expected diastolic blood pressure (minimum blood pressure) and is predetermined as the pressure at which the decompression process should be terminated.

[0082] During the decompression process described above, the observer 80 listens to the Korotkoff sounds Kc produced by the arteries passing through the upper arm 91 using a stethoscope 89 while watching the cuff pressure Pc displayed in real time as a bar graph 50b on the display 50 shown in Figure 2. Then, in step S111 in Figure 3, the observer 80 presses the HOLD button 52B at time t1, which is delayed by a reaction time td1 minutes from the time t0 at which the observer determined that the Korotkoff sounds Kc had started to be produced (i.e., the time when the first Korotkoff sound Kcf was heard from a state of silence), as illustrated in the middle of Figure 4. This corresponds to the first press during the decompression process described above. Here, the observer 80 can make the determination that the Korotkoff sounds Kc have started to be produced (and the determination that the Korotkoff sounds Kc have stopped to be produced, as described later) with the same feeling as when using a traditional mercury sphygmomanometer. Therefore, it can be said that this is highly convenient for observers who are accustomed to using traditional mercury sphygmomanometers. It is assumed that observer 80's reaction time td1 will not normally exceed one beat T.

[0083] When the HOLD button 52B is pressed (Yes in step S110 of Figure 3), the control unit 110 acts as a recording unit and, in step S112 of Figure 3, determines whether the HOLD button 52B has been pressed for the first time or for the second time or later during the depressurization process. In this example, the memory 51 is equipped with a counter (not shown) that counts the number of times the HOLD button 52B has been pressed. This counter is reset each time the depressurization process starts and counts the number of times the HOLD button 52B has been pressed. By referring to the count value of this counter, the control unit 110 can determine whether the HOLD button 52B has been pressed for the first time or for the second time or later. If the HOLD button 52B has been pressed for the first time, in step S113, the control unit 110 determines that the first timing signal t1 (represented by the same sign as time t1 for simplicity) was input at the time t1 when the first press occurred, as illustrated in the middle of Figure 4. The control unit 110 then acts as a recording processing unit and identifies the data pair corresponding to the time indicated by the first timing signal t1 from the dataset DS1 stored in the memory 51 (in the example in the lower part of Figure 4, the data pair with beat number N=3 stored immediately before time t1). Furthermore, the control unit 110 stores the cuff pressure Pc included in the identified data pair in the memory 51 as the systolic blood pressure value. In the example in the lower part of Figure 4, 135 mmHg (shown by the dashed frame A1) included in the data pair with beat number N=3 is stored as the systolic blood pressure value. Along with this, in this example, the obtained systolic blood pressure value of 135 mmHg is displayed on the display unit 50. This display may be shown on the display unit 50 as a digital value, for example, "Maximum blood pressure 135 mmHg", and / or as a horizontal bar-shaped mark indicating the pressure value by its position along the scale 50a, as shown by mark M1 in Figure 10(A) described later. This allows observer 80 to easily recognize the obtained systolic blood pressure value by looking at the display 50. At this point, the dataset DS1 only contains data pairs from beat number N=1 to beat number N=3.

[0084] After this, the decompression process described above proceeds, and the cuff pressure Pc decreases. Again in step S111 in Figure 3, observer 80 presses the HOLD button 52B at time t2, which is a reaction time td2 minutes later than t21, the time when he determined that the Korotkoff tone Kc had stopped being heard (that is, the time when he first determined that it had stopped being heard one beat T later than the time t20 when the last Korotkoff tone Kce was heard), as illustrated in the middle of Figure 4. This corresponds to the second press in the decompression process described above. It is assumed that observer 80's reaction time td2 does not usually exceed one beat T.

[0085] When the HOLD button 52B is pressed (Yes in step S110 of Figure 3), the control unit 110, in step S112 of Figure 3, refers to the count value of the counter to determine whether it is the first time the HOLD button 52B has been pressed during the depressurization process or a subsequent press. If it is the second time the HOLD button 52B has been pressed, in step S114, the control unit 110 determines that a second timing signal t2 (represented by the same sign as time t2 for simplicity) was input at time t2 when the second press occurred, as illustrated in the middle of Figure 4. The control unit 110 then acts as a recording processing unit and identifies the data pair corresponding to the time indicated by the second timing signal t2 from the dataset DS1 stored in memory 51 (in the example in the lower part of Figure 4, the data pair with beat number N=18 stored immediately before time t2), and further identifies the data pair corresponding to one beat prior to that data pair (in the example in the lower part of Figure 4, the data pair with beat number N=17). Furthermore, the control unit 110 stores the cuff pressure Pc included in the latter data pair in the memory 51 as a corrected diastolic blood pressure value. In the example in the lower part of Figure 4, 95 mmHg (shown by the dashed frame A2) included in the data pair with beat number N=17 is stored as the corrected diastolic blood pressure value. In addition, in this example, the control unit 110 acts as a third display processing unit and displays the above corrected diastolic blood pressure value of 95 mmHg on the display unit 50. This display may be shown on the display unit 50 as a digital value, for example, "Minimum blood pressure 95 mmHg", and / or as a horizontal bar-shaped mark indicating the pressure value by its position along the scale 50a, as shown by mark M2 in Figure 10(A) described later. This allows the observer 80 to easily recognize the corrected diastolic blood pressure value by looking at the display unit 50.

[0086] In Figure 3, the phrase "from the second time onward" in step S112 is intended to accommodate the possibility that the HOLD button 52B may be pressed three or more times during the decompression process. Specifically, if subject 90 exhibits arrhythmia, the beat may be interrupted. Also, if the subject is pregnant, Korotkoff sounds may continue to be heard even at low pressures (e.g., 30 mmHg). The quality of Korotkoff sounds changes in five stages from the start to the stop. Each interval of the sound is called a "phase," and these are divided into phases I through V. Therefore, both the point where the quality of the Korotkoff sound changes (beginning of phase IV) and the last sound of the Korotkoff sound may be recorded. For this reason, as mentioned above, this is intended to accommodate the possibility that the HOLD button 52B may be pressed three or more times during the decompression process.

[0087] After this, as the decompression process proceeds and the current cuff pressure Pc falls below a predetermined pressure (30 mmHg in this example) (Yes in step S115), the control unit 110 terminates processing of this blood pressure recording method flow. The observer 80 opens the manual valve 33 to lower the cuff pressure Pc (step S116). Alternatively, the observer 80 may open the manual valve 33 to lower the cuff pressure Pc as soon as the corrected diastolic blood pressure value is recorded.

[0088] Thus, in this blood pressure monitor 1A, the control unit 110 acts as a recording processing unit, and during the decompression process, the data pair corresponding to the time indicated by the second timing signal t2 is identified from a series of data pairs stored in the memory 51. The cuff pressure Pc included in the data pair corresponding to one beat prior to the identified data pair is recorded as the corrected diastolic blood pressure value. According to the inventor's analysis described above, the corrected diastolic blood pressure value corresponds to the cuff pressure Pc corresponding to the time t20 when the Korotkoff sound Kc was actually last heard, not to the time t21 when the observer 80 first determined that the sound had stopped being heard after being continuously heard with each beat. Therefore, according to the blood pressure recording method flow shown in Figure 3 using the blood pressure monitor 1A, the phenomenon in which the lowest blood pressure is evaluated as being approximately one beat lower can be corrected.

[0089] Furthermore, it is thought that a small reaction time td1 and td2 is required from the time the observer 80 determines that the Korotkoff sound Kc has started to be produced until they press the HOLD button 52B, and from the time the observer 80 determines that the Korotkoff sound Kc has stopped to they press the HOLD button 52B. However, in this blood pressure monitor 1A, during the decompression process, the control unit 110 acts as the first data storage unit, so that data pairs are sequentially stored in the memory 51 without being affected by such reaction times td1 and td2. Therefore, the data pairs identified by the control unit 110 acting as the recording processing unit are stored without being affected by the observer 80's reaction times td1 and td2. Also, it is assumed that the observer's reaction times td1 and td2 do not usually exceed one beat. As a result, the recorded systolic blood pressure value and the corrected diastolic blood pressure value are practically unaffected by the observer 80's reaction times td1 and td2.

[0090] It should be noted that there may be a slight delay (time interval) between the time when the rising point (Pf) of a beat occurs and the time when the Korotkoff tone (Kc) of that beat occurs. However, this delay usually does not amount to half a beat, so it does not substantially reduce the accuracy of blood pressure measurement (recording).

[0091] As described above, this first embodiment allows for more accurate recording of systolic blood pressure and diastolic blood pressure (corrected diastolic blood pressure) compared to the conventional example. Moreover, in this first embodiment, the control unit 110 determines whether the operation of the operation unit 52 is the first or second time during the decompression process, so both the systolic blood pressure and the corrected diastolic blood pressure can be recorded quickly. Furthermore, the observer 80 can end the blood pressure measurement as soon as the corrected diastolic blood pressure is recorded, even if the decompression process is still in progress.

[0092] The inventors experimentally verified the accuracy of the systolic blood pressure values ​​and the corrected diastolic blood pressure values ​​recorded by this first embodiment. Specifically, the inventors used a blood pressure monitor 1A to simultaneously perform blood pressure measurement using the normal auscultation method and blood pressure measurement using the hold function (HOLD button 52B) according to the blood pressure recording method flow shown in Figure 3. In blood pressure measurement using the normal auscultation method, the observer 80 read the maximum and minimum blood pressure based on the Korotkoff sounds Kc heard by the stethoscope 89 while looking at the cuff pressure Pc displayed in real time as a bar graph 50b on the display unit 50 (these read values ​​are called "auscultation values"). On the other hand, in blood pressure measurement using the hold function, while viewing the cuff pressure Pc displayed in real time as a bar graph 50b on the display unit 50, the observer 80 pressed the HOLD button 52B at times corresponding to t1 and t2 in the middle of Figure 4, based on the Korotkoff sounds Kc heard by the stethoscope 89, and recorded the cuff pressure at that time (this recorded value is called the "HOLD value"). Then, the difference between the HOLD value and the auscultatory value obtained each of the 60 measurements (HOLD value - auscultatory value) was calculated. Figure 5(A) shows a scatter plot for systolic blood pressure (maximum blood pressure), with the auscultatory value on the horizontal axis and the difference (HOLD value - auscultatory value) on the vertical axis. Figure 5(B) shows a scatter plot for diastolic blood pressure (minimum blood pressure), with the auscultatory value on the horizontal axis and the difference (HOLD value - auscultatory value) on the vertical axis. As can be seen from these figures, the average difference (HOLD value - auscultation value) for systolic blood pressure (maximum blood pressure) was -1.5 mmHg. On the other hand, the average difference (HOLD value - auscultation value) for diastolic blood pressure (minimum blood pressure) was -1.2 mmHg. Thus, in this verification experiment, no significant difference was observed in systolic blood pressure (maximum blood pressure) compared to conventional cases. However, it can be said that the phenomenon of underestimating diastolic blood pressure (minimum blood pressure) by about one beat was corrected.

[0093] In the blood pressure monitor 1A described above, a manual pump 32 and a manual valve 33 are provided as the cuff pressure adjustment unit, and the cuff pressure Pc is adjusted by manually increasing or decreasing the pressure. However, this is not the only option. For example, a commercially available electronic blood pressure monitor (for example, the upper arm blood pressure monitor HEM-7120 series manufactured by Omron Healthcare Co., Ltd.) may be equipped with an electric pump and valve, and the control unit 110 may automatically increase or decrease the pressure of the cuff. In this case, the observer 80 does not need to operate the manual pump 32 and manual valve 33, and can use one hand (the right hand in the example in Figure 2) exclusively to press the HOLD button 52B during the depressurization process. Therefore, it is convenient for the observer 80. This point is the same in the second to fourth embodiments described later.

[0094] (Second Embodiment) Figure 6 shows the block configuration of a blood pressure monitor 1B as a second embodiment of the blood pressure recording device of the present invention. This blood pressure monitor 1B differs from the blood pressure monitor 1A described above in that the HOLD buttons on the operation unit 52 include a systolic blood pressure HOLD button 52B1 as a first switch that receives an instruction to record the systolic blood pressure value, and a diastolic blood pressure HOLD button 52B2 as a second switch that receives an instruction to record the diastolic blood pressure value. In this example, both the systolic blood pressure HOLD button 52B1 and the diastolic blood pressure HOLD button 52B2 are momentary type (self-resetting type) switches. The hardware configuration of this blood pressure monitor 1B other than the operation unit 52 is the same as that of the blood pressure monitor 1A. In Figure 6, the same reference numerals are used for components that are the same as those in Figure 1, and redundant explanations are omitted.

[0095] In this example, observer 80 is scheduled to press the systolic blood pressure HOLD button 52B1 at the time they determine that the Korotkoff sound Kc has started to be produced. Observer 80 is also scheduled to press the diastolic blood pressure HOLD button 52B2 at the time they determine that the Korotkoff sound Kc has stopped being produced.

[0096] Figure 7 shows a flow chart of a blood pressure recording method in one embodiment in which an observer 80 measures and records the blood pressure of a subject 90's upper arm 91 using a blood pressure monitor 1B. In preparation for blood pressure measurement, in this example, as shown in Figure 2, the observer 80 wraps the cuff 20 around the subject 90's upper arm 91 and places the stethoscope 89 against the part of the subject 90's upper arm 91 through which the artery passes (the part corresponding to the downstream side of the cuff 20). The manual valve 33 is also assumed to be open.

[0097] Steps S201 to S209 of the blood pressure recording method flow in Figure 7 are performed in exactly the same way as steps S101 to S109 of the blood pressure recording method flow in Figure 3.

[0098] In this example, while steps S208 and S209 in Figure 7 are being processed during the decompression process, in step S210, the control unit 110 determines whether the systolic blood pressure HOLD button 52B1 has been pressed. Also, in step S213, the control unit 110 determines whether the diastolic blood pressure HOLD button 52B2 has been pressed. If neither the systolic blood pressure HOLD button 52B1 nor the diastolic blood pressure HOLD button 52B2 has been pressed (No in step S210, No in step S213), the control unit 110 continues the processing in steps S208 to S210 and S213 as long as the current cuff pressure Pc is above a predetermined pressure (30 mmHg in this example) (No in step S216).

[0099] During the decompression process described above, if the observer 80 presses the systolic blood pressure HOLD button 52B1 as shown in step S211 of Figure 7 (Yes in step S210 of Figure 7), in step S212, the control unit 110 determines that a first timing signal t1 was input at the time t1 when the systolic blood pressure HOLD button 52B1 was pressed, as illustrated in the middle section of Figure 4. The control unit 110 then acts as a recording processing unit and identifies the data pair corresponding to the time indicated by the first timing signal t1 from the dataset DS1 stored in memory 51 (in the example in the lower section of Figure 4, the data pair with beat number N=3 stored immediately before time t1). Furthermore, the control unit 110 stores the cuff pressure Pc included in the identified data pair as the systolic blood pressure value in memory 51. In the example in the lower section of Figure 4, 135 mmHg (shown by the dashed box A1) included in the data pair with beat number N=3 is stored as the systolic blood pressure value. In addition, in this example, the obtained systolic blood pressure value of 135 mmHg is displayed on the display unit 50. This display may be shown on the display unit 50 as a digital value, for example, "Maximum blood pressure 135 mmHg", and / or as a horizontal bar-shaped mark indicating the pressure value by its position along the scale 50a, as shown by mark M1 in Figure 10(A) described later.

[0100] On the other hand, during the decompression process described above, if the observer 80 presses the diastolic blood pressure HOLD button 52B2 as shown in step S214 of Figure 7 (Yes in step S213 of Figure 7), in step S215, the control unit 110 determines that a second timing signal t2 was input at the time t2 when the diastolic blood pressure HOLD button 52B2 was pressed, as illustrated in the middle of Figure 4. The control unit 110 then acts as a recording processing unit and identifies the data pair corresponding to the time indicated by the second timing signal t2 from the dataset DS1 stored in memory 51 (in the example in the lower part of Figure 4, the data pair with beat number N=18 stored immediately before time t2), and further identifies the data pair corresponding to one beat prior to that data pair (in the example in the lower part of Figure 4, the data pair with beat number N=17). Furthermore, the control unit 110 stores the cuff pressure Pc included in the latter data pair in memory 51 as a corrected diastolic blood pressure value. In the example shown in the lower part of Figure 4, the corrected diastolic blood pressure value of 95 mmHg (shown by the dashed box A2) included in the data pair with beat number N=17 is stored. In this example, the control unit 110 also acts as a third display processing unit to display the corrected diastolic blood pressure value of 95 mmHg on the display unit 50. This display may be shown on the display unit 50 as a digital value, for example, "Minimum blood pressure 95 mmHg", and / or as a horizontal bar-shaped mark indicating the pressure value by its position along the scale 50a, as shown by mark M2 in Figure 10(A) described later. This allows the observer 80 to easily recognize the obtained systolic blood pressure value and the corrected diastolic blood pressure value by looking at the display unit 50.

[0101] After this, as the decompression process proceeds and the current cuff pressure Pc falls below a predetermined pressure (30 mmHg in this example) (Yes in step S216 of Figure 7), the control unit 110 terminates processing of this blood pressure recording method flow. The observer 80 opens the manual valve 33 to lower the cuff pressure Pc (step S217). Alternatively, the observer 80 may open the manual valve 33 to lower the cuff pressure Pc as soon as the corrected diastolic blood pressure value is recorded.

[0102] According to this second embodiment, systolic blood pressure and diastolic blood pressure (corrected diastolic blood pressure) can be recorded with high accuracy, similar to the first embodiment. Moreover, according to this second embodiment, both the systolic blood pressure and the corrected diastolic blood pressure can be recorded quickly, depending on the observer's intention (whether to record the systolic blood pressure or the diastolic blood pressure). Furthermore, even if the decompression process is still in progress, the observer 80 can end the blood pressure measurement as soon as the corrected diastolic blood pressure is recorded. In addition, since the control unit 110 does not need to determine whether the operation of the operation unit 52 is the first or second time during the decompression process, the processing by the control unit 110 is simplified.

[0103] (Third embodiment) Figure 8 shows the block configuration of a blood pressure monitor 1C as a third embodiment of the blood pressure recording device of the present invention. This blood pressure monitor 1C differs from the blood pressure monitor 1A described above in that, in addition to the power button 52A and the HOLD button 52B, the operation unit 52 includes a selection button 52C as a selection operation unit. In this example, the selection button 52C is a momentary type (self-resetting type) switch. The hardware configuration of this blood pressure monitor 1C other than the operation unit 52 is the same as that of blood pressure monitor 1A. In Figure 8, the same reference numerals are used for components that are the same as those in Figure 1, and redundant explanations are omitted.

[0104] In this example, observer 80 is expected to select the option that they believe corresponds to their diastolic blood pressure value from the options (cuff pressure Pc included in the data pair) (marks M1 and M2 in Figure 10, described later) displayed on the display unit 50, which correspond to the time when the first and second timing signals t1 and t2 were input, using the selection button 52C.

[0105] Figure 9 shows a flow chart of a blood pressure recording method in one embodiment in which an observer 80 measures and records the blood pressure of a subject 90's upper arm 91 using a blood pressure monitor 1C. In preparation for blood pressure measurement, in this example, as shown in Figure 2, the observer 80 wraps the cuff 20 around the subject 90's upper arm 91 and places the stethoscope 89 in contact with the portion of the subject 90's upper arm 91 through which the artery passes (the portion corresponding to the downstream side of the cuff 20). The manual valve 33 is also assumed to be open.

[0106] Steps S301 to S309 of the blood pressure recording method flow in Figure 9 are performed in exactly the same way as steps S101 to S109 of the blood pressure recording method flow in Figure 3.

[0107] In this example, while steps S308 and S309 in Figure 9 are being processed during the depressurization process, in step S310, the control unit 110 determines whether or not the HOLD button 52B has been pressed. If the HOLD button 52B has not been pressed (No in step S310), the control unit 110 continues the processing in steps S308 to S310 as long as the current cuff pressure Pc is above a predetermined pressure (30 mmHg in this example) (No in step S313). In this example, it is assumed that the dataset DS2 shown in Figure 11 is stored in memory 51.

[0108] During the decompression process described above, when the observer 80 presses the HOLD button 52B for the first time, as shown in step S311 of Figure 9 (Yes in step S310 of Figure 9), in step S312, the control unit 110 acts as a data pair identification unit and identifies the data pair corresponding to the time t1 when the button was pressed (in the example of Figure 11, the data pair with beat number N=3) from the dataset DS2 stored in memory 51. Furthermore, the control unit 110 maintains information indicating the identified data pair with beat number N=3 by setting a flag F1 for that identified data pair with beat number N=3. At the same time, the control unit 110 acts as a second display processing unit and causes the display unit 50 to display the cuff pressure Pc (135 mmHg, shown by the dashed frame B1 in the example of Figure 11) included in the identified data pair with beat number N=3 as a blood pressure value option. In this example, it is displayed as a horizontal bar-shaped mark indicating the pressure value by its position along the scale 50a, as shown by mark M1 in Figure 10(A). At this point, the dataset DS2 only contains data pairs from beat number N=1 to beat number N=3.

[0109] Next, during the decompression process described above, if the observer 80 presses the HOLD button 52B a second time, as shown in step S311 of Figure 9 (Yes in step S310 of Figure 9), then in step S312, the control unit 110 acts as a data pair identification unit and identifies the data set stored in memory 51. DS2 From these, the control unit 110 identifies the data pair corresponding to the time t2 when the button was pressed (in the example in Figure 11, the data pair with beat number N=18). Furthermore, the control unit 110 maintains information indicating the identified data pair with beat number N=18 by setting a flag F2 for that data pair. At the same time, the control unit 110 acts as a second display processing unit and causes the display unit 50 to display the cuff pressure Pc (93 mmHg, shown by the dashed frame B2 in the example in Figure 11) included in the identified data pair with beat number N=18 as a blood pressure value option. In this example, it is displayed as a horizontal bar-shaped mark indicating the pressure value by its position along the scale 50a, as shown by mark M2 in Figure 10(A).

[0110] Furthermore, if the HOLD button 52B is pressed three or more times during the decompression process described above, the control unit 110 acts as a data pair identification unit each time it is pressed, identifying the data pair from the dataset DS1 stored in memory 51 that corresponds to the time the button was pressed. In addition, the control unit 110 maintains information indicating the identified data pair with beat number N by flagging that data pair. At the same time, the control unit 110 acts as a second display processing unit, causing the display unit 50 to display the cuff pressure Pc included in the identified data pair with beat number N as a blood pressure value option. Note that "three or more times" is intended to accommodate the possibility that the HOLD button 52B may be pressed three or more times during the decompression process described above. For more details, if the subject 90 is showing arrhythmia, the beat may be interrupted midway. Also, if the woman is pregnant, Korotkoff sounds may continue to be heard even at low pressures (e.g., 30 mmHg). The quality of Korotkoff sounds changes in five stages from the time they are produced until they stop. Each interval of sound is called a "phase," and they are divided into phases I through V. Therefore, both the point where the quality of the Korotkoff tone changes (beginning of phase IV) and the last sound of the Korotkoff tone are sometimes recorded. For this reason, as mentioned above, the system is designed to accommodate the possibility that the HOLD button 52B may be pressed three or more times during the decompression process.

[0111] After this, as the decompression process progresses and the current cuff pressure Pc falls below a predetermined pressure (30 mmHg in this example) (Yes in step S313 of Figure 9), the observer 80 opens the manual valve 33 to lower the cuff pressure Pc and terminate the decompression process (step S314). At the end of this decompression process, the control unit 110 acts as a second display processing unit, maintaining the display of mark M1 representing the obtained blood pressure value of 135 mmHg and mark M2 representing the obtained blood pressure value of 93 mmHg, as illustrated in Figure 10(A). The control unit 110 then waits for a selection to be made by the selection button 52C (step S315 of Figure 9). At this stage, the observer 80 selects the option that they believe corresponds to their diastolic blood pressure value from among the marks M1 and M2 displayed on the display unit 50, which are options corresponding to the time t1 and t2 when the HOLD button 52B was pressed (i.e., the time when the timing signal was input).

[0112] In this example, each time observer 80 presses the selection button 52C, the selection candidates sequentially switch, with mark M1 flashing (indicated by a radial mark surrounding a horizontal bar) as shown in Figure 10(B), or mark M2 flashing as shown in Figure 10(C). If three or more marks representing options are displayed, the selection candidates cycle through among the three or more marks.

[0113] In this example, observer 80 presses and holds the selection button 52C for, for example, 3 seconds or more to select mark M2 when mark M2 is flashing as shown in Figure 10(C). Then, in step S317 in Figure 9, the control unit 110 acts as a recording processing unit and identifies the data pair containing the cuff pressure represented by the selection button 52C (in the example in Figure 11, the data pair with beat number N=18 in the dataset DS2 with flag F2 set) as the data pair that observer 80 selected as corresponding to the diastolic blood pressure value. Furthermore, the control unit 110 identifies the data pair corresponding to one beat prior to the identified data pair (in the example in Figure 11, the data pair with beat number N=17 in the dataset DS2). Then, the cuff pressure Pc contained in the latter data pair is stored in memory 51 as the corrected diastolic blood pressure value. In this example, as shown in Figure 11, the 95 mmHg (dashed box) contained in the data pair with beat number N=17 in the dataset DS2 B21 By setting the flag F21 (as shown in Figure 10(D)), the information that the corrected diastolic blood pressure value is 95 mmHg is stored. At the same time, in this example, the control unit 110 acts as a third display processing unit and displays the corrected diastolic blood pressure value of 95 mmHg on the display unit 50. In this example, instead of displaying mark M2, this display is shown as a horizontal bar-shaped mark indicating the pressure value by its position along the scale 50a, as shown by mark M21 in Figure 10(D). Also in this example, the remaining mark M1 displays the cuff pressure Pc (135 mmHg, shown by the dashed frame B1 in the example of Figure 11) contained in the data pair of beat number N=3 for which flag F1 was set. As a result, the observer 80 can easily recognize the obtained systolic blood pressure value and the corrected diastolic blood pressure value by looking at marks M1 and M21 displayed on the display unit 50. In this way, the systolic blood pressure value and the corrected diastolic blood pressure value are recorded.

[0114] According to this third embodiment, systolic blood pressure values ​​and diastolic blood pressure values ​​(corrected diastolic blood pressure values) can be recorded with high accuracy, similar to the first embodiment. Moreover, according to this third embodiment, the corrected diastolic blood pressure values ​​can be recorded according to the observer 80's selection (the selection of which option corresponds to the diastolic blood pressure value).

[0115] Figure 12 shows a modified flow chart of the blood pressure recording method shown in Figure 9. In preparation for blood pressure measurement, in this example, as shown in Figure 2, the observer 80 wraps the cuff 20 around the upper arm 91 of the subject 90 and places the stethoscope 89 against the part of the upper arm 91 of the subject 90 through which the artery passes (the part corresponding to the downstream side of the cuff 20). The manual valve 33 is also assumed to be open.

[0116] Steps S401 to S414 of the blood pressure recording method flow in Figure 12 are performed in exactly the same way as steps S301 to S314 of the blood pressure recording method flow in Figure 9.

[0117] In the blood pressure recording method flow shown in Figure 12, when the HOLD button 52B is pressed two or more times during the decompression process, in step S415 after the completion of the decompression process, the control unit 110 acts as a recording processing unit and uses the data pair corresponding to the time t2 when the last operation was performed (in the example in Figure 11, the data pair with beat number N=18) from among the data pairs with flags (let's call them F1 and F2) set in the dataset DS2 as the data pair corresponding to the time indicated by the second timing signal t2. That is, without asking the observer 80 to select an option that is thought to correspond to diastolic blood pressure, the control unit 110 stores the cuff pressure Pc contained in the data pair corresponding to one beat prior to the data pair with beat number N=18 as the corrected diastolic blood pressure value in memory 51. In the example in Figure 11, the 95 mmHg (indicated by the dashed box) contained in the data pair with beat number N=17 in the dataset DS2. B21The data is stored by setting the flag F21 (as shown in Figure 10(D)). In addition, in this example, the control unit 110 acts as a third display processing unit and displays the corrected diastolic blood pressure value of 95 mmHg on the display unit 50. In this example, instead of displaying mark M2, this display is shown as a horizontal bar-shaped mark indicating the pressure value by its position along the scale 50a, as shown by mark M21 in Figure 10(D). Also in this example, the remaining mark M1 displays the cuff pressure Pc (135 mmHg in this example, shown by the dashed frame B1) included in the data pair of beat number N=3 for which flag F1 was set. As a result, the observer 80 can easily recognize the obtained systolic blood pressure value and the corrected diastolic blood pressure value by looking at marks M1 and M21 displayed on the display unit 50. In this way, the systolic blood pressure value and the corrected diastolic blood pressure value are recorded.

[0118] According to the blood pressure recording method flow chart in Figure 12, the processing performed by the control unit 110, which acts as the recording processing unit, becomes simpler. In addition, the selection button 52C can be omitted from the hardware configuration of the blood pressure monitor 1C.

[0119] In the first to third embodiments, upon commencement of the decompression process, the control unit 110 acts as a first data storage unit and begins the process of associating the beat number N, which is a code corresponding to the time when the rising edge Pf of a beat occurs, with the cuff pressure Pc at the time when the rising edge Pf of a beat occurs, and sequentially storing them as data pairs in the memory 51. However, the invention is not limited to this. The control unit 110 may also begin sequentially storing the data pairs in the memory 51 during the decompression process, starting with the data pair corresponding to the time when the HOLD button 52B was pressed for the first time (in the example of Figure 11, the data pair with beat number N=3). This saves resources in the memory 51.

[0120] (Fourth Embodiment) Figure 13 shows the block configuration of a blood pressure monitor 1D as a fourth embodiment of the blood pressure recording device of the present invention. This blood pressure monitor 1D differs from the blood pressure monitor 1A described above in that it includes a microphone 40 mounted on the cuff 20 and an A / D conversion circuit 410 mounted on the main body 10. The microphone 40 converts the sound generated by the artery passing through the upper arm 91 of the subject 90 into an electrical signal, which is an audio signal Ks, and outputs it. The audio signal Ks output by the microphone 40 is transmitted to the A / D conversion circuit 410 through wiring 71 extending from the cuff 20 to the main body 10 as shown in Figure 13. The A / D conversion circuit 410 converts the audio signal Ks from an analog value to a digital value and transmits it to the control unit 110. The other hardware configurations of this blood pressure monitor 1D are the same as those of the blood pressure monitor 1A. In Figure 13, the same reference numerals are used for components that are the same as those in Figure 1, and redundant explanations are omitted.

[0121] Figure 14 shows a flow chart of a blood pressure recording method in one embodiment in which an observer 80 measures and records the blood pressure of a subject 90's upper arm 91 using a blood pressure monitor 1D. In preparation for blood pressure measurement, in this example, as shown in Figure 2, the observer 80 wraps the cuff 20 around the subject 90's upper arm 91 and places the stethoscope 89 against the part of the subject 90's upper arm 91 through which the artery passes (the part corresponding to the downstream side of the cuff 20). The manual valve 33 is also assumed to be open.

[0122] Steps S501 to S507 of the blood pressure recording method flow in Figure 14 are performed in exactly the same way as steps S101 to S107 of the blood pressure recording method flow in Figure 3.

[0123] When depressurization begins (Yes in step S507), the control unit 110 performs the processes in steps S508 to S514 during this depressurization process.

[0124] First, the microphone 40 converts the sound generated by the artery passing through the upper arm 91 of the subject 90 into an electrical signal, which is a sound signal Ks, and outputs it. As shown in the upper part of Figure 15, this sound signal Ks includes a pulsed Korotkoff tone signal Kca, which represents a Korotkoff tone, as an electrical signal (AC signal). The sound signal Ks output by the microphone 40 is transmitted to the control unit 110 as a digital value via the wiring 71 and A / D conversion circuit 410 shown in Figure 13. Here, in step S508 in Figure 14, the control unit 110 acts as a Korotkoff tone signal detection unit and detects the Korotkoff tone signal Kca from the sound signal Ks, for example as shown in the middle part of Figure 15. The Korotkoff tone signal Kca can be detected by the control unit 110 setting a threshold Th slightly higher than the background noise level ba for the sound signal Ks, for example as shown in the upper part of Figure 15, and extracting the component of the sound signal Ks that exceeds that threshold Th. The timing at which the Korotkoff tone signal Kca is detected is assumed to coincide with the timing at which observer 80 hears the Korotkoff tone Kc with a stethoscope 89 (i.e., the processing time required for the control unit 110 to detect the Korotkoff tone signal Kca from the sound signal Ks is negligible).

[0125] In parallel with this process, in step S509 of Figure 14, the control unit 110 acts as a second data storage unit and starts the process of associating the beat number N, which is a code corresponding to the time when the Korotkoff tone signal Kca was detected, with the cuff pressure Pc at the time the Korotkoff tone signal Kca was detected, and sequentially storing them as data pairs in the memory 51. In this example, as shown in the lower part of Figure 15, a series of data pairs obtained during this decompression process (referred to as a "data set") DS3 is stored, with the data pair of beat number N=1 and cuff pressure Pc=125 (mmHg) being stored next, the data pair of beat number N=2 and cuff pressure Pc=122 (mmHg) being stored next, and so on, until finally the data pair of beat number N=15 and cuff pressure Pc=85 (mmHg) being stored. Since this process is performed without the operation of the observer 80, this data set DS3 is stored without being affected by the reaction time (described later) when the observer 80 presses the HOLD button 52B. Note that in the lower section of Figure 15, the columns marked with "-" do not contain any data pairs.

[0126] Alternatively, the time at which the Korotkoff tone signal Kca was generated and the cuff pressure Pc at that time may be directly associated and sequentially stored as a data pair in memory 51. However, by using the beat number N as described above, the resources of memory 51 can be saved. This is the same as in the first embodiment.

[0127] During the decompression process described above, while steps S508 and S509 in Figure 14 are being performed, in step S510, the control unit 110 determines whether or not the HOLD button 52B has been pressed. If the HOLD button 52B has not been pressed (No in step S510), the control unit 110 continues the process from steps S508 to S510 as long as the current cuff pressure Pc is above a predetermined pressure (30 mmHg in this example) (No in step S515). Note that 30 mmHg is a pressure lower than the expected minimum blood pressure and is predetermined as the pressure at which the decompression process should be terminated.

[0128] During the decompression process described above, the observer 80 observes the cuff pressure Pc, which is displayed in real time as a bar graph 50b on the display unit 50 shown in Figure 2, and, in this example, as in the first embodiment, listens to the Korotkoff sound Kc generated by the artery passing through the upper arm 91 using a stethoscope 89 (as mentioned above, the timing of the generation of this Korotkoff sound Kc is assumed to coincide with the timing of the generation of the Korotkoff sound signal Kca shown in the middle of Figure 15). Then, in step S511 of Figure 14, the observer 80 determines the time when the Korotkoff sound Kc has started to be generated, as illustrated in the middle of Figure 15 (i.e., from silence to the first Korotkoff sound) Kcaf At time t1, which is delayed by reaction time td1 minutes from the time (t0) when the sound was heard, press the HOLD button 52B. This corresponds to the first press in the decompression process described above. It is assumed that the observer 80's reaction time td1 will not normally exceed one beat T.

[0129] When the HOLD button 52B is pressed (Yes in step S510 of Figure 14), the control unit 110 acts as a recording processing unit and, in step S512 of Figure 14, determines whether the HOLD button 52B has been pressed for the first time or for the second time or later during the depressurization process. In this example, the control unit 110 can determine whether the HOLD button 52B has been pressed for the first time or for the second time or later by referring to the count value of the counter described in the first embodiment. If the HOLD button 52B has been pressed for the first time, in step S513, the control unit 110 determines that a first timing signal t1 (represented by the same sign as time t1 for simplicity) has been input, as illustrated in the middle of Figure 15. The control unit 110 then acts as a recording processing unit and identifies the data pair corresponding to the time indicated by the first timing signal t1 (in the example in the lower part of Figure 15, the data pair with beat number N=1 stored immediately before time t1) from the dataset DS3 stored in the memory 51. Furthermore, the control unit 110 stores the cuff pressure Pc contained in the identified data pair as the systolic blood pressure value in the memory 51. In the example in the lower part of Figure 15, 125 mmHg (shown by the dashed frame C1) contained in the data pair with beat number N=1 is stored as the systolic blood pressure value. In this example, the obtained systolic blood pressure value of 125 mmHg is also displayed on the display unit 50. This display may be shown as a digital value on the display unit 50, for example, "Maximum blood pressure 125 mmHg", and / or as a horizontal bar-shaped mark indicating the pressure value by its position along the scale 50a, as shown by mark M1 in Figure 10(A). This allows the observer 80 to easily recognize the obtained systolic blood pressure value by looking at the display unit 50. At this point, the dataset DS3 only contains the data pair with beat number N=1.

[0130] After this, the decompression process described above proceeds, and the cuff pressure Pc decreases. Again in step S511 in Figure 14, observer 80 determines the time when the generation of the Korotkoff tone Kc has stopped, as illustrated in the middle of Figure 15 (i.e., the last Korotkoff tone). KkaeAt time t20, when the sound was first heard, and then at time t21 (the time when it was first determined that the sound had stopped, with a delay of one beat T), the HOLD button 52B is pressed at time t2, which is a further delay of reaction time td2 minutes. This corresponds to the second press during the decompression process described above. It is assumed that the observer 80's reaction time td2 will not normally exceed one beat T.

[0131] When the HOLD button 52B is pressed (Yes in step S510 of Figure 14), the control unit 110 determines in step S512 of Figure 14 whether the HOLD button 52B has been pressed for the first time or for the second time or later during the decompression process. If the HOLD button 52B has been pressed for the second time, in step S514, the control unit 110 refers to the count value of the counter and determines that a second timing signal t2 (represented by the same sign as time t2 for simplicity) has been input, as illustrated in the middle of Figure 15. The control unit 110 then acts as a recording processing unit and identifies the last data pair stored in the memory 51 from the dataset DS3 stored in the memory 51, going back from the time indicated by the second timing signal t2 (in the example in the lower part of Figure 15, the data pair with beat number N=15), and stores the cuff pressure Pc included in the identified data pair in the memory 51 as a corrected diastolic blood pressure value. In the example in the lower part of Figure 15, Corrected diastolic blood pressure The 85 mmHg value (shown in the dashed box C2) included in the data pair with beat number N=15 is stored. In this example, the control unit 110 acts as a third display processing unit to display the corrected diastolic blood pressure value of 85 mmHg on the display unit 50. This display may be shown on the display unit 50 as a digital value, for example, "Minimum blood pressure 85 mmHg", and / or, figure As shown in mark M2 in 10(A), the pressure value may be displayed as a horizontal bar-shaped mark indicating its position along the scale 50a. This allows the observer 80 to easily recognize the corrected diastolic blood pressure value by looking at the display 50.

[0132] Note that the second "and subsequent" in step S512 of Figure 14 is intended to accommodate the possibility that the HOLD button 52B may be pressed three or more times during the decompression process described above. Specifically, if subject 90 is exhibiting arrhythmia, the beat may be interrupted midway. Also, if the subject is pregnant, Korotkoff sounds may continue to be heard even at low pressures (e.g., 30 mmHg). The quality of Korotkoff sounds changes in five stages from the start to the stop. Each interval of the sound is called a "phase," and they are divided into phases I to V. Therefore, both the point where the quality of the Korotkoff sound changes (beginning of phase IV) and the last sound of the Korotkoff sound may be recorded. For this reason, as mentioned above, it is intended to accommodate the possibility that the HOLD button 52B may be pressed three or more times during the decompression process described above.

[0133] After this, as the decompression process proceeds and the current cuff pressure Pc falls below a predetermined pressure (30 mmHg in this example) (Yes in step S515), the control unit 110 terminates processing of this blood pressure recording method flow. The observer 80 opens the manual valve 33 to lower the cuff pressure Pc (step S516). Alternatively, the observer 80 may open the manual valve 33 to lower the cuff pressure Pc as soon as the corrected diastolic blood pressure value is recorded.

[0134] Thus, in this blood pressure monitor 1D, the control unit 110 acts as a recording processing unit, and from a series of data pairs stored in the memory 51 during the decompression process, the last data pair stored, working backward from the time indicated by the second timing signal t2, is identified, and the cuff pressure Pc included in that identified data pair is recorded as the corrected diastolic blood pressure value. According to the inventor's analysis described above, the corrected diastolic blood pressure value corresponds to the cuff pressure Pc at the time t20 when the Korotkoff sound Kc was actually last heard, not at the time t21 when the observer 80 first determined that the sound had stopped being heard after being continuously heard with each beat. Therefore, according to the blood pressure recording method flow shown in Figure 14 using the blood pressure monitor 1D, the phenomenon in which the lowest blood pressure is evaluated as being about one beat lower can be corrected.

[0135] Furthermore, it is thought that a small reaction time td1 and td2 is required from the time the observer 80 determines that the Korotkoff sound Kc has started to be produced until the HOLD button 52B is pressed, and from the time the observer 80 determines that the Korotkoff sound Kc has stopped to the HOLD button 52B. However, in this blood pressure monitor 1D, during the decompression process, the control unit 110 acts as a second data storage unit, so that data pairs are sequentially stored in the memory 51 without being affected by such reaction times td1 and td2. Therefore, the data pairs identified by the control unit 110 acting as the recording processing unit are stored without being affected by the observer 80's reaction times td1 and td2. As a result, the recorded systolic blood pressure value and the corrected diastolic blood pressure value are practically unaffected by the observer 80's reaction times td1 and td2.

[0136] As described above, this fourth embodiment allows for more accurate recording of systolic blood pressure values ​​and diastolic blood pressure values ​​(corrected diastolic blood pressure values) compared to the conventional example.

[0137] Furthermore, in this fourth embodiment, the dataset DS3 associates the beat number N, which is a code corresponding to the time when the Korotkoff sound signal Kca is detected, with the cuff pressure Pc at the time the Korotkoff sound signal Kca is detected, and stores them sequentially in the memory 51 as data pairs. Therefore, compared to the first embodiment, there is no possibility that the discrepancy (time interval) between the time when the rise point Pf of a beat occurs and the time when the Korotkoff sound Kc of that beat occurs will affect the accuracy of blood pressure measurement (recording). Consequently, systolic blood pressure values ​​and diastolic blood pressure values ​​(corrected diastolic blood pressure values) can be recorded with even greater accuracy.

[0138] In the blood pressure monitor 1D described above, the microphone 40 is mounted on the cuff 20, but this is not the only option. For example, as in the blood pressure monitor 1E shown in Figure 16, the microphone 40 may be mounted on the main body 10, and in this example, it may receive sound generated by the arteries passing through the upper arm 91 of the subject 90 through an air pipe 38d connected to an air pipe 38. In this case as well, similar to the blood pressure monitor 1D, the microphone 40 can convert the sound generated by the arteries passing through the upper arm 91 of the subject 90 into an electrical signal, which is an audio signal Ks, and output it. Therefore, by using this blood pressure monitor 1E and performing the blood pressure recording method flow shown in Figure 14, systolic blood pressure values ​​and diastolic blood pressure values ​​(corrected diastolic blood pressure values) can be recorded with high accuracy. Moreover, when using the blood pressure monitor 1E, there is no need to extend the wiring 71 between the cuff 20 and the main body 10, thus simplifying the configuration of the device.

[0139] Furthermore, in this fourth embodiment, the observer 80 presses the HOLD button 52B upon hearing the Korotkoff sound Kc generated by the artery passing through the upper arm 91 using a stethoscope 89, similar to the first embodiment. However, it is not limited to this. For example, an electrophonic sound conversion device such as the speaker 54 shown in Figure 17 below may be provided, and the Korotkoff sound signal Kca may be reproduced as the Korotkoff sound Kc using this electrophonic sound conversion device. In that case, the observer 80 may press the HOLD button 52B upon hearing the reproduced Korotkoff sound Kc.

[0140] (Fifth embodiment) Figure 17 shows the block configuration of a blood pressure measurement system 1F as a fifth embodiment of the blood pressure recording device of this invention. This blood pressure measurement system 1F is a modified version of the blood pressure monitor 1D in Figure 13, adapted to enable remote medical consultation. In Figure 17, the same reference numerals are used for components that are the same as those in Figure 13, and redundant explanations are omitted.

[0141] This blood pressure measurement system 1F broadly consists of a patient-side device 100A installed at the location of the subject (in this example, the patient) 90, who has an upper arm 91, and a physician-side device 100B installed at the location of the observer (in this example, the physician) 80. The location of the subject 90 refers to the location of the residence where the patient, acting as subject 90, lives. The location of the observer 80 refers to the location of the medical institution where the physician, acting as observer 80, works.

[0142] The patient-side device 100A comprises a cuff 20 and a main unit 10A. The cuff 20 is equipped with a microphone 40. The main unit 10A is equipped with a control unit 110A, a pressure sensor 31 as a pressure detection unit, an electric pump 32A and a solenoid valve 33A as cuff pressure adjustment units, a measurement button 52D as an operation unit, a memory 51A, a power supply unit 53A, A / D conversion circuits 310 and 410, a pump drive circuit 320, a solenoid valve drive circuit 330, a communication unit 190A, and a display unit 55.

[0143] The sound signal Ks output by the microphone 40 is transmitted to the A / D conversion circuit 410 via the wiring 71 extending from the cuff 20 to the main unit 10A.

[0144] The control unit 110A includes a CPU (Central Processing Unit) as a processor and controls the operation of the entire patient-side device 100A.

[0145] An air pipe 38a is connected to the pressure sensor 31 in a fluid-flow manner, an air pipe 38b is connected to the electric pump 32A in a fluid-flow manner, and an air pipe 38c is connected to the solenoid valve 33A in a fluid-flow manner. In this example, air pipes 38a, 38b, and 38c merge to form a single air pipe 38, which is connected to the cuff 20 in a fluid-flow manner.

[0146] The electric pump 32A is driven by the pump drive circuit 320 based on a control signal from the control unit 110A, supplying air to pressurize the cuff 20. The solenoid valve 33A is opened and closed by the solenoid valve drive circuit 330 based on a control signal from the control unit 110A, and is used to discharge air from or seal air into the cuff 20. This allows the cuff 20 to be automatically pressurized or depressurized.

[0147] In this example, the measurement button 52D is a momentary type (self-resetting type) switch. When pressed once, the measurement operation by the patient-side device 100A begins, and when pressed again, the measurement operation by the patient-side device 100A is interrupted or stopped.

[0148] Memory 51A stores program data for controlling the patient-side device 100A, setting data for configuring various functions of the patient-side device 100A, and data from blood pressure measurement and blood pressure measurement results. Memory 51A is also used as work memory when the program is executed.

[0149] The power supply unit 53A supplies or cuts off power to the control unit 110A, memory 51, pressure sensor 31, electric pump 32A, solenoid valve 33A, and other parts within the main unit 10A, depending on whether the measurement button 52D is turned on or off.

[0150] The communication unit 190A is configured to function as a transmitter based on a control signal from the control unit 110A during the measurement operation by the patient-side device 100A. In this example, during the cuff pressure Pc depressurization process, the communication unit 190A sequentially transmits the cuff pressure signal representing the cuff pressure Pc detected by the pressure sensor 31 as measurement data, either alone or in time-synchronized with the sound signal Ks output by the microphone 40 and the cuff pressure signal representing the cuff pressure Pc detected by the pressure sensor 31.

[0151] The display unit 55 consists of an LCD (Liquid Crystal Display) and displays predetermined information according to control signals from the control unit 110A. In this example, the display unit 55 digitally displays the cuff pressure Pc being measured, for example, as "xxx mmHg". The display unit 55 may also consist of an organic EL (Electro Luminescence) display or may include an LED (Light Emitting Diode).

[0152] On the other hand, the physician's device 100B includes a main unit 10B. The main unit 10B is equipped with a control unit 110B, a display unit 50, an operating unit 52, a speaker 54 as an electrophonic sound conversion device, a memory 51B, a power supply unit 53B, and a communication unit 190B.

[0153] The control unit 110B includes a CPU (Central Processing Unit) as a processor and controls the operation of the entire physician-side device 100B.

[0154] The display unit 50 and the operating unit 52 are the same as those in the blood pressure monitor 1D in Figure 13 (and therefore in the blood pressure monitor 1A in Figure 1).

[0155] During the measurement operation by the patient-side device 100A, speaker 54 reproduces the Korotkoff tone signal Kca, which is an electrical signal, as the Korotkoff tone Kc based on a control signal from the control unit 110B. Instead of speaker 54, headphones, earphones, or the like may be provided as the electro-sound conversion device.

[0156] Memory 51B stores program data for controlling the physician-side device 100B, configuration data for setting various functions of the physician-side device 100B, and data from blood pressure measurement and blood pressure measurement results. Memory 51B is also used as work memory when the program is executed.

[0157] The power supply unit 53B supplies or cuts off power to the control unit 110B, memory 51B, and other parts within the main unit 10B in response to the on / off status of the power button 52A.

[0158] In this example, the communication unit 190B is connected to the communication unit 190A of the patient-side device 100A via a network 190 such as the Internet, enabling data communication. In this example, the communication unit 190B receives measurement data in real time from the communication unit 190A of the patient-side device 100A while the patient-side device 100A is performing a measurement operation, and passes it to the control unit 110B.

[0159] Figures 18 and 19 show a flow chart of a blood pressure recording method in one embodiment in which an observer 80 measures and records the blood pressure of a subject 90's upper arm 91 using a blood pressure measurement system 1F. In Figures 18 and 19, the processing and decisions made by the control unit 110A of the patient-side device 100A are outlined with solid lines on the left, and the processing and decisions made by the control unit 110B of the physician-side device 100B are outlined with solid lines on the right. Terminal 1 in the flow chart in Figure 18 is continuous with terminal 1 in the flow chart in Figure 19, and terminal 2 in the flow chart in Figure 18 is continuous with terminal 2 in the flow chart in Figure 19. In Figure 19, as previously described, manual operation and manual input by the observer 80 are outlined with dashed lines.

[0160] It is assumed that the physician's device 100B is powered on beforehand and that initialization has been performed on the physician's device 100B as shown in step S701 of Figure 18. As a result, the contents of the data set in memory 51B are assumed to be reset. Also, in preparation for blood pressure measurement, in this example, it is assumed that the subject 90 has wrapped the cuff 20 around their upper arm 91 and is wearing it.

[0161] When subject 90 presses the measurement button 52D on the patient-side device 100A, the pressure sensor initialization process shown in step S601 of Figure 18 is performed on the patient-side device 100A.

[0162] Next, as shown in steps S602 and S702 of Figure 18, the communication unit 190A of the patient-side device 100A and the communication unit 190B of the physician-side device 100B communicate via the network 190 (indicated by arrow C1 in Figure 18) to synchronize the patient-side device 100A and the physician-side device 100B. If synchronization is not achieved (NO in steps S602 and S702 of Figure 18), the system waits until synchronization is achieved. Once synchronization is achieved (YES in steps S602 and S702 of Figure 18), it becomes possible for the patient-side device 100A and the physician-side device 100B to exchange data in sync.

[0163] With synchronization established, in step S603 of Figure 18, the control unit 110A of the patient-side device 100A begins to display the current cuff pressure Pc detected by the pressure sensor 31 on the display unit 55. Subsequently, the control unit 110A acts as a cuff pressure adjustment unit, closing the solenoid valve 33A in step S604 and starting to drive the electric pump 32A in step S605. Accordingly, in step S606, the control unit 110A begins to transmit a cuff pressure signal representing the current cuff pressure Pc detected by the pressure sensor 31 from the communication unit 190A of the patient-side device 100A to the communication unit 190B of the physician-side device 100B via the network 190 (indicated by arrow C2 in Figure 18). Furthermore, in step S607, the control unit 110A acts as a cuff pressure adjustment unit and, as shown in the upper part of Figure 15, determines whether the cuff pressure Pc has reached a predetermined pressure Pcmax, which is approximately 30 mmHg higher than the expected systolic blood pressure. If it has not reached this level (NO in step S607), it returns to step S605 and continues pressurizing. This temporarily stops the blood flow through the artery in the upper arm 91 of the subject 90. Once the cuff pressure Pc reaches pressure Pcmax (YES in step S607 in Figure 18), the control unit 110A stops the electric pump 32A in step S608 and gradually opens the solenoid valve 33A in step S609. This initiates a reduction in the cuff pressure Pc, typically at a rate of 2-3 mmHg / second. In this example, since the pressure adjustment is performed automatically, the patient, as subject 90, does not need to adjust the pressure, which is convenient.

[0164] As described above, in step S606 of Figure 18, when the patient-side device 100A begins transmitting a cuff pressure signal representing the current cuff pressure Pc, in step S703, the control unit 110B of the physician-side device 100B receives the cuff pressure signal via the communication unit 190B. Then, in step S704, the control unit 110B acts as the first display processing unit and starts processing to display the current cuff pressure Pc detected by the pressure sensor 31 on the display unit 50 as a bar graph 50b along the scale 50a in real time.

[0165] In the cuff pressure Pc depressurization process initiated in step S609 of Figure 18, the control unit 110A of the patient-side device 100A acts as a Korotkoff sound signal detection unit, as shown in step S610 of Figure 19, and detects a pulsed Korotkoff sound signal Kca from the sound signal Ks output by the microphone 40, as shown in the middle of Figure 15. Then, in step S611 of Figure 19, the control unit 110A synchronizes the pulsed Korotkoff sound signal Kca and the cuff pressure signal representing the cuff pressure Pc in time and transmits them sequentially as measurement data through the communication unit 190A, which acts as a transmitter (indicated by arrow C3 in Figure 19).

[0166] In step S706 of Figure 19, the communication unit 190B of the physician-side device 100B acts as a receiver and receives measurement data in real time from the patient-side device 100A while the patient-side device 100A is performing a measurement operation, and passes it to the control unit 110B. In step S707, the control unit 110B acts as a second data storage unit and associates the beat number N corresponding to the time when the Korotkoff sound signal Kca was detected with the cuff pressure Pc at the time the Korotkoff sound signal Kca was detected, and sequentially stores them as data pairs in the memory 51B. As in the fourth embodiment, this is referred to as the data set DS3 (see Figure 15).

[0167] During the depressurization process described above, observer 80 listens to the Korotkoff tone Kc reproduced by speaker 54 based on the Korotkoff tone signal Kca, while watching the cuff pressure Pc displayed in real time as a bar graph 50b on display unit 50. In step S709 of Figure 19, observer 80 determines the time when the Korotkoff tone Kc began to be generated (i.e., from silence to the first Korotkoff tone), as illustrated in the middle section of Figure 15. Kcaf At time t1, which is delayed by a reaction time td1 minutes from the time t0 when the sound was heard, the HOLD button 52B is pressed. If this is the first press during the decompression process described above, the control unit 110B determines that the first timing signal t1 (represented by the same sign as time t1 for simplicity) has been input. The control unit 110B then acts as a recording processing unit and performs the processing in steps S708, S710, and S711 in Figure 19 (the same as the processing in steps S510, S512, and S513 in Figure 14) to identify the data pair corresponding to the time indicated by the first timing signal t1 (in the example in the lower part of Figure 15, the data pair with beat number N=1 stored immediately before time t1) from the dataset DS3 stored in memory 51. Furthermore, the control unit 110B stores the cuff pressure Pc included in the identified data pair as the systolic blood pressure value in memory 51B. In the example shown in the lower part of Figure 15, the systolic blood pressure value of 125 mmHg (indicated by the dashed box C1) included in the data pair with beat number N=1 is stored. In this example, the obtained systolic blood pressure value of 125 mmHg is also displayed on the display unit 50.

[0168] After this, the decompression process described above proceeds, and the cuff pressure Pc decreases. Again in step S709 in Figure 19, observer 80 determines the time when the generation of the Korotkoff tone Kc, as illustrated in the middle of Figure 15, has stopped (i.e., the last Korotkoff tone). KkaeAt time t2, which is one beat T after the time t20 when the sound was heard, the HOLD button 52B is pressed at time t2, which is a further delay of reaction time td2 minutes. If this is the second press during the decompression process described above, the control unit 110B determines that a second timing signal t2 (represented by the same sign as time t2 for simplicity) has been input. The control unit 110B then acts as a recording processing unit and performs the processing in steps S708, S710, and S712 in Figure 19 (the same as the processing in steps S510, S512, and S514 in Figure 14) to identify the last data pair stored in the data set DS3 stored in memory 51, going back from the time indicated by the second timing signal t2 (in the example in the lower part of Figure 15, the data pair with beat number N=15), and stores the cuff pressure Pc included in the identified data pair in memory 51B as the corrected diastolic blood pressure value. In the example in the lower part of Figure 15, Corrected diastolic blood pressure The 85 mmHg value (shown in the dashed box C2) included in the data pair with beat number N=15 is stored. In this example, the control unit 110B also acts as a third display processing unit to display the corrected diastolic blood pressure value of 85 mmHg on the display unit 50. This allows the observer 80 to visually confirm the obtained systolic blood pressure value and the corrected diastolic blood pressure value.

[0169] Subsequently, as the decompression process progresses and the current cuff pressure Pc falls below a predetermined pressure (30 mmHg in this example) (Yes in steps S612 and S713 in Figure 19), the control unit 110A of the patient-side device 100A opens the solenoid valve 33A in step S613. As a result, air is exhausted from the cuff 20 into the atmosphere via the air pipes 38, 38c and the solenoid valve 33A. At the same time, in step S714, the control unit 110B of the physician-side device 100B transmits the obtained systolic blood pressure value and the corrected diastolic blood pressure value to the patient-side device 100A via the communication unit 190B (indicated by arrow C4 in Figure 19). Then, in step S614, the control unit 110A of the patient-side device 100A receives the obtained systolic blood pressure value and the corrected diastolic blood pressure value via the communication unit 190A. In step S615, the control unit 110A of the patient-side device 100A displays the obtained systolic blood pressure value and the corrected diastolic blood pressure value as digital values ​​on the display unit 55. This allows the subject 90 to visually confirm the obtained systolic blood pressure value and the corrected diastolic blood pressure value.

[0170] According to this fifth embodiment, systolic blood pressure values ​​and diastolic blood pressure values ​​(corrected diastolic blood pressure values) can be recorded with high accuracy, similar to the fourth embodiment. Moreover, even if the location of the observer 80 (for example, the location of the medical institution where the physician, acting as observer 80, works) is far from the location of the subject 90 (for example, the location of the residence where the patient, acting as subject 90, lives), the obtained systolic blood pressure values ​​and diastolic blood pressure values ​​(corrected diastolic blood pressure values) can be recorded by exchanging the above measurement data between the communication unit 190A of the patient-side device 100A and the communication unit 190B of the physician-side device 100B. The obtained systolic blood pressure values ​​and diastolic blood pressure values ​​(corrected diastolic blood pressure values) may be stored in the medical institution's electronic medical record, for example, via the communication unit 190B.

[0171] Network 190 is typically the internet, but it could also be a hospital LAN (Local Area Network) or a one-to-one communication network.

[0172] Furthermore, in this fifth embodiment, the patient-side device 100A, located at the location of the subject 90, and the physician-side device 100B, located at the location of the observer 80, operate in synchronous manner. However, the embodiment is not limited to this, and the patient-side device 100A and the physician-side device 100B may operate independently. For example, after the patient-side device 100A performs the processing from step S601 in Figure 18 to step S610 in Figure 19 (excluding the processing in steps S602 and S606 in Figure 18), instead of transmitting the measurement data to the physician-side device 100B in real time in step S611 in Figure 19, the pulsed Korotkoff tone signal Kca and the cuff pressure signal representing the cuff pressure Pc are temporally associated and temporarily recorded in memory 51A as measurement data (referred to as "second measurement data"). After this, the patient-side device 100A completes the processes from steps S612 to S613 in Figure 19. After storing the second measurement data in memory 51A, the patient-side device 100A transmits the second measurement data recorded in memory 51A to the physician-side device 100B at any time in accordance with a request from the physician-side device 100B. The physician-side device 100B temporarily records the received second measurement data in memory 51B. The observer 80 activates the physician-side device 100B and plays back the second measurement data temporarily recorded in memory 51B to determine the blood pressure value. For example, the observer 80 looks at the cuff pressure Pc displayed on the display 50 based on the second measurement data, listens to Korotkoff sounds through the speaker 54, and presses the HOLD button 52B at the time when the observer determines that the Korotkoff sounds have started to occur and / or when the Korotkoff sounds have stopped to occur. This allows the systolic blood pressure value and / or diastolic blood pressure value (corrected diastolic blood pressure value) to be recorded based on the second measurement data. In this way, the subject 90 and the observer 80 do not need to operate their respective devices simultaneously. Therefore, convenience is increased for both the subject 90 and the observer 80.

[0173] In the embodiments described above, the measurement site was assumed to be the upper arm 91 of the subject 90, but it is not limited to this. The measurement site may also be the wrist or lower limb of the subject 90.

[0174] In the embodiments described above, the HOLD button 52B is mounted on the main body 10 of each blood pressure monitor 1A to 1E or on the main body 10B of the physician's device 100B, but it is not limited to this. The HOLD button 52B may be provided at a distance from the main bodies 10 and 10B, and may input a timing signal to the control units 110 and 110B via wired or wireless connection.

[0175] Furthermore, each of the blood pressure monitors 1A to 1E and the blood pressure measurement system 1F described above may be equipped with a printer to print out the obtained systolic blood pressure values ​​and diastolic blood pressure values ​​(corrected diastolic blood pressure values) onto paper such as roll paper.

[0176] In each of the embodiments described above, the display unit 50 for the observer 80 is designed to mimic a traditional mercury sphygmomanometer, displaying a vertically aligned scale 50a and a bar graph 50b that expands and contracts along the scale 50a as an image to represent the cuff pressure Pc. However, it is not limited to this. For example, the displays 56, 57, and 58 shown in Figures 20(A), 20(B), and 20(C), respectively, may also be used. The display unit 56 shown in Figure 20(A) comprises an LED section 56L consisting of numerous LEDs arranged in an arc shape on the front panel 56P, and a scale 56a printed in an area along the inner circumference of the LED section 56L on the front panel 56P. The display unit 56 represents the cuff pressure Pc by changing the illuminated range of the LED section 56L (for convenience, the range shown in black in Figure 20(A)) 56b. The display unit 57 shown in Figure 20(B) is equipped with an LCD unit 57D that occupies a circular area on the front panel 56P. The LCD unit 57D displays, as an image, a scale 57a arranged in a ring (or arc) shape, and a pointer 57b that rotates around the center 50c like the minute hand of a clock, representing the cuff pressure Pc. The display unit 58 shown in Figure 20(C) is equipped with a 3-digit 7-segment (figure-eight shaped) type LCD unit 58D on the main body 10C. The LCD unit 58D displays the cuff pressure Pc as a digital value. Thus, various types of displays can be used for the observer 80. The same applies to the display unit 55 (see Figure 17) for the subject 90.

[0177] The embodiments described above are illustrative, and various modifications are possible without departing from the scope of this invention. Each of the above embodiments can stand on its own, but they can also be combined. Furthermore, various features within different embodiments can stand on their own, but they can also be combined. [Explanation of symbols]

[0178] 1A, 1B, 1C, 1D, 1E Blood pressure monitor 1F Blood pressure measurement system 10, 10A, 10B Main Unit 20 Cuffs 31 Pressure Sensor 32 Manual pumps 32A Electric Pump 33 Manual valve 33A Solenoid valve 40 Microphones 50,55,56,57,58 Display 110, 110A, 110B Control Unit 190 Networks 190A,190B Communication Department

Claims

1. A blood pressure recording device configured to measure and record blood pressure based on Korotkoff sounds generated by an artery passing through a measurement site of a subject, A cuff that is attached around the measurement site; A cuff pressure adjusting unit for increasing or decreasing the cuff pressure, which is the pressure of the cuff; a pressure detection unit that detects the cuff pressure during a process of reducing the cuff pressure by the cuff pressure adjustment unit; a time detection unit that detects, during the decompression process, a time at which a waveform characteristic point of a pulse occurs for each beat of a pulse wave exhibited by an artery passing through the measurement site; a first data storage unit that associates, during the decompression process, a time at which a waveform characteristic point of the beat occurs or a code corresponding to that time with the cuff pressure at the time at which the waveform characteristic point of the beat occurs, and sequentially stores the data in a memory as a data pair; A display device; a first display processing unit that performs processing for displaying the cuff pressure detected by the pressure detection unit on the display; an operation unit configured to be operated by an observer who listens to Korotkoff sounds generated by an artery passing through the measurement site with a stethoscope while watching the cuff pressure displayed on the display by the first display processing unit during the decompression process, the operation unit is adapted to input a first timing signal indicating a time when the observer judges that the Korotkoff sounds have started to be generated, and / or a second timing signal indicating a time when the observer judges that the Korotkoff sounds have stopped to be generated, a recording processing unit that identifies a data pair corresponding to one beat before the data pair corresponding to the time indicated by the second timing signal from among the series of data pairs stored in the memory during the decompression process, and records the cuff pressure included in the identified data pair as a corrected diastolic blood pressure value. A blood pressure recording device comprising:

2. 2. The blood pressure recording device according to claim 1, The recording processing unit identifies a data pair corresponding to a time indicated by the first timing signal from the series of data pairs stored in the memory, and records the cuff pressure included in the identified data pair as a systolic blood pressure value. A blood pressure recording device.

3. 3. The blood pressure recording device according to claim 2, The recording processing unit determines whether the operation of the operation unit is the first operation or the second or subsequent operation during the depressurization process, and records the systolic blood pressure value using the time when the first operation is performed as the time indicated by the first timing signal, and records the corrected diastolic blood pressure value using the time when the second or subsequent operation is performed as the time indicated by the second timing signal. A blood pressure recording device.

4. 3. The blood pressure recording device according to claim 2, the operation unit includes a first switch for receiving an instruction to record a systolic blood pressure value and a second switch for receiving an instruction to record a diastolic blood pressure value; The recording processing unit records the systolic blood pressure value during the depressurization process, using the time when the first switch is operated as the time indicated by the first timing signal, and records the corrected diastolic blood pressure value, using the time when the second switch is operated as the time indicated by the second timing signal. A blood pressure recording device.

5. 2. The blood pressure recording device according to claim 1, further comprising: a data pair specifying unit that specifies a data pair corresponding to a time when the operation unit is operated each time the operation unit is operated during the decompression process, and maintains information indicating each specified data pair; a second display processing unit that causes the display device to display, as options, the cuff pressures included in the data pairs identified by the data pair identifying unit from among a series of data pairs stored in the memory during the decompression process; a selection operation unit for selecting an option that the observer considers to be a diastolic blood pressure value from among the options displayed on the display device, After the depressurization process is completed, the recording processing unit records the corrected diastolic blood pressure value using a data pair including a cuff pressure represented by the option selected by the selection operation unit, among the series of data pairs stored in the memory during the depressurization process, as a data pair corresponding to the time indicated by the second timing signal. A blood pressure recording device.

6. 2. The blood pressure recording device according to claim 1, a data pair specifying unit that specifies a data pair corresponding to a time when the operation unit is operated during the decompression process and maintains information indicating each specified data pair; After the decompression process is completed, the recording processing unit uses the data pair corresponding to the time when the last operation was performed among the data pairs identified by the data pair identification unit as the data pair corresponding to the time indicated by the second timing signal, and records the corrected diastolic blood pressure value. A blood pressure recording device.

7. 7. The blood pressure recording device according to claim 1, further comprising: a third display processing unit that causes the display to display the corrected diastolic blood pressure value as a digital value and / or as a mark indicating a pressure value by a position along a scale. A blood pressure recording device comprising:

8. 7. The blood pressure recording device according to claim 1, The first data storage section is configured to sequentially store the data pairs in the memory during the depressurization process, starting from the data pair corresponding to the time when the first operation was performed by the operation section. A blood pressure recording device.

9. A blood pressure recording method for measuring and recording blood pressure at a measurement site of a subject using the blood pressure recording device according to claim 1, comprising: The cuff is attached to the measurement site so as to surround it, and a stethoscope is placed on a portion of the measurement site through which an artery passes; The cuff pressure is increased by the cuff pressure adjusting unit to temporarily stop the blood flow in the artery passing through the measurement site, and then, in the process of decreasing the cuff pressure, The cuff pressure is detected by the pressure detection unit. the time detection unit detects, for each beat of a pulse wave indicated by an artery passing through the measurement site, a signal indicating a time at which a waveform characteristic point of that beat occurred; the first data storage unit associates the time at which the waveform characteristic point of the beat occurred or a code corresponding to the time with the cuff pressure at the time at which the waveform characteristic point of the beat occurred, and sequentially stores the data pairs in the memory; an observer who listens to Korotkoff sounds generated by an artery passing through the measurement site with the stethoscope while watching the cuff pressure displayed on the display by the first display processing unit operates the operation unit to input at least a second timing signal indicating a time when it is determined that the generation of the Korotkoff sounds has stopped; During the depressurization process or after completion of the depressurization process, the recording processing unit identifies a data pair that corresponds to one beat before the data pair corresponding to the time indicated by the second timing signal from the series of data pairs stored in the memory during the depressurization process, and records the cuff pressure included in the identified data pair as a corrected diastolic blood pressure value. A blood pressure recording method comprising:

10. A blood pressure recording device configured to measure and record blood pressure based on Korotkoff sounds generated by an artery passing through a measurement site of a subject, A cuff that is attached around the measurement site; A cuff pressure adjusting unit for increasing or decreasing the cuff pressure, which is the pressure of the cuff; a pressure detection unit that detects the cuff pressure during a process of reducing the cuff pressure by the cuff pressure adjustment unit; a microphone that converts a sound generated by an artery passing through the measurement site during the decompression process into an electric sound signal and outputs the sound signal; a Korotkoff sound signal detection unit that detects a Korotkoff sound signal indicative of a Korotkoff sound from the sound signal output by the microphone; a second data storage unit that associates the time at which the Korotkoff sound signal is detected or a code corresponding to the time with the cuff pressure at the time at which the Korotkoff sound signal is detected during the decompression process, and sequentially stores the data in a memory as a data pair; A display device; a first display processing unit that performs processing for displaying the cuff pressure detected by the pressure detection unit on the display; an operation unit configured to be operated by an observer who listens to Korotkoff sounds generated by an artery passing through the measurement site with a stethoscope or hears Korotkoff sounds indicated by the Korotkoff sound signal with an electro-acoustic conversion device while watching the cuff pressure displayed on the display by the first display processing unit during the decompression process, the operation unit is adapted to input a first timing signal indicating a time when the observer judges that the Korotkoff sounds have started to be generated, and / or a second timing signal indicating a time when the observer judges that the Korotkoff sounds have stopped to be generated, a recording processing unit that identifies the last stored data pair from the series of data pairs stored in the memory during the decompression process, going back from the time indicated by the second timing signal, and records the cuff pressure included in the identified data pair as a corrected diastolic blood pressure value. A blood pressure recording device comprising:

11. 11. The blood pressure recording device according to claim 10, At the location of the subject having the measurement site, the cuff, the cuff pressure adjusting unit, the pressure detecting unit, the microphone, and the Korotkoff sound signal detecting unit are disposed, a transmission unit is provided that, during the decompression process, synchronizes the Korotkoff sound signal detected by the Korotkoff sound signal detection unit with a cuff pressure signal representing the cuff pressure detected by the pressure detection unit in time and sequentially transmits them as measurement data; At the location of the observer, which is separate from the location of the subject, A receiving unit for receiving the measurement data is provided, the second data storage unit, the memory, the display, the electro-acoustic conversion device, the first display processing unit, the operation unit, and the recording processing unit are arranged; During the decompression process, based on the received measurement data, The first display processing unit causes the display device to display the cuff pressure, the second data storage unit associates the time at which the Korotkoff sound signal is detected or a code corresponding to that time with the cuff pressure at the time at which the Korotkoff sound signal is detected, and sequentially stores the data in the memory as a data pair; During the decompression process, an observer who hears the Korotkoff sound indicated by the Korotkoff sound signal from the electro-acoustic conversion device while watching the cuff pressure displayed on the display by the first display processing unit operates the operation unit to input at least the second timing signal. A blood pressure recording device.

12. A blood pressure recording method for measuring and recording blood pressure at a measurement site of a subject using the blood pressure recording device according to claim 10, comprising the steps of: The cuff is attached to the measurement site so as to surround the measurement site, The microphone is arranged so as to capture a sound generated by an artery passing through the measurement site, or in addition to the arrangement of the microphone, the stethoscope is placed on a portion of the measurement site through which the artery passes, The cuff pressure is increased by the cuff pressure adjusting unit to temporarily stop the blood flow in the artery passing through the measurement site, and then, in the process of decreasing the cuff pressure, The cuff pressure is detected by the pressure detection unit. The microphone converts a sound generated by an artery passing through the measurement site into the sound signal and outputs the sound signal. The Korotkoff sound signal detection unit detects the Korotkoff sound signal from the sound signal output by the microphone; the second data storage unit associates the time at which the Korotkoff sound signal is detected or a code corresponding to that time with the cuff pressure at the time at which the Korotkoff sound signal is detected, and sequentially stores the data pairs in the memory; an observer who listens to Korotkoff sounds generated by an artery passing through the measurement site with the stethoscope or listens to Korotkoff sounds indicated by the Korotkoff sound signal with the electro-acoustic conversion device while watching the cuff pressure displayed on the display by the first display processing unit operates the operation unit to input at least a second timing signal indicating a time when it is determined that the generation of the Korotkoff sounds has stopped; During the depressurization process or after the end of the depressurization process, the recording processing unit identifies the last stored data pair from the series of data pairs stored in the memory during the depressurization process, going back from the time indicated by the second timing signal, and records the cuff pressure included in the identified data pair as a corrected diastolic blood pressure value. A blood pressure recording method comprising:

13. A blood pressure recording device according to any one of claims 1 to 6, claim 10 or claim 11, The first display processing unit is adapted to perform a process of displaying the cuff pressure detected by the pressure detection unit on the display as a bar graph along a scale. A blood pressure recording device.

Images