Biological information display device and biological information display method

Abstract

To provide a biological information display device and a biological information display method capable of easily checking a change in hemodynamics of a subject.SOLUTION: A biological information display device M includes: a reception part 74 for receiving a start signal showing a start timing of treatment for a subject, and an end signal showing an end timing of the treatment; a calculation part 70 for calculating a moving average of a pulse wave propagation time of the subject, calculating a hemodynamics parameter of the subject using the calculated moving average, and calculating a rate of change in the hemodynamics parameter in a period from the start timing to the end timing on the basis of the start signal and the end signal received by the reception part 74; and a display control part 72 for outputting the calculated rate of change in a display part 71.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a biological information display device and a biological information display method.

[0002] Conventionally, when administering a treatment such as administering an infusion to a subject, changes in parameters related to the subject's hemodynamics, such as stroke volume or cardiac output (hereinafter referred to as "hemodynamic parameters"), are used as useful parameters for checking the subject's condition. For example, a small amount of infusion is administered, and if the rate of change between the value of the hemodynamic parameter before administration and the value of the hemodynamic parameter after administration is equal to or greater than a certain value, a decision is made to continue the administration of the infusion, or to terminate the administration in order to switch to another treatment if the rate of change is less than the certain value. Furthermore, Patent Document 1 discloses a method for calculating cardiac output using pulse wave transit time. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-312947 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in order to check the change in hemodynamics before and after the treatment, for example, the operator performing the treatment records the values ​​of the hemodynamic parameters at the start of the treatment and at the end of the treatment, and performs calculations using these values. This requires a lot of time and effort, and a technology that can easily check the change in the hemodynamics of the subject is desired.

[0005] The present disclosure provides a biological information display device and a biological information display method that allow changes in the circulatory dynamics of a subject to be easily confirmed. [Means for solving the problem]

[0006] A biological information display device according to one aspect of the present disclosure includes: a receiving unit that receives a start signal indicating a timing to start a treatment on a subject and an end signal indicating a timing to end the treatment; a calculation unit that calculates a moving average value of a pulse wave transit time of the subject, calculates a circulatory dynamics parameter of the subject using the calculated moving average value, and further calculates a rate of change of the circulatory dynamics parameter during a period from the start timing to the end timing based on the start signal and the end signal received by the receiving unit; and a display control unit that controls output of the calculated rate of change to a display unit. [Effects of the Invention]

[0007] According to the present disclosure, changes in the hemodynamics of a subject can be easily confirmed. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing the configuration of a biological information processing device (biological information display device) according to the present invention. [Figure 2] FIG. 2 is a diagram showing an example of a measurement form using a monitor device which is an example of the biological information processing device shown in FIG. [Figure 3] FIG. 3 is a diagram showing an example of a screen displayed on the display unit shown in FIG. [Figure 4] FIG. 4 is a diagram showing an example of a screen displayed when a new treatment for a subject is started. [Figure 5] FIG. 5 is a diagram for explaining an operation for instructing switching of the pulse wave transit time used in calculating the circulatory dynamics parameters. [Figure 6] FIG. 6 is a flowchart illustrating the flow of an operation for switching the pulse wave transit time used to calculate circulatory dynamics parameters in the biological information processing device according to the embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a biological information display device and a biological information display method according to the present invention will be described below with reference to the accompanying drawings.

[0010] [Configuration of biometric information processing device] Fig. 1 is a diagram showing the configuration of a biological information processing device (biological information display device) M according to the present invention. Fig. 2 is a diagram showing an example of a measurement form using a monitor device M1, which is an example of the biological information processing device M shown in Fig. 1.

[0011] The bioinformation processing device M includes a display device 1 that calculates and controls the display of circulatory dynamics parameters related to the circulatory dynamics of the subject, a blood pressure measuring device 2 that measures blood pressure during systole and diastole, a respiration measuring device 4, an invasive blood pressure measuring device 5, a reception unit 6, electrocardiogram electrodes 31, a photoelectric pulse wave detection sensor 32, a measurement data transmitter 65, and a display unit 71.

[0012] The blood pressure measurement device 2 is a device that measures the blood pressure of a subject by a non-invasive blood pressure (NIBP) measurement method, and includes a cuff 21, an exhaust valve 22, a pressure pump 23, a pressure sensor 24, a cuff pressure detection unit 25, and an A / D converter 26. Specifically, as shown in Fig. 2, the blood pressure measurement device 2 measures blood pressure by attaching the cuff 21 to the upper arm of the subject.

[0013] The interior of the cuff 21 is opened or closed to the atmosphere by opening or closing an exhaust valve 22. The exhaust valve 22 is opened or closed based on, for example, a control signal output from the monitor device M1. Air is supplied to the cuff 21 from a pressure pump 23. The supply of air is controlled based on, for example, the control signal output from the monitor device M1.

[0014] A pressure sensor 24 is connected to the cuff 21, and the sensor output of the pressure sensor 24 is detected by a cuff pressure detection unit 25. The sensor output from the cuff pressure detection unit 25 is converted into a digital signal by an A / D converter 26, and then input to the NIBP pulse pressure measurement means 11 of the display device 1.

[0015] As shown in Fig. 2, the electrocardiogram electrodes 31 are attached to the chest of the subject, and measurements are made using the occurrence of an R wave on the electrocardiogram as the reference point for time intervals. The electrocardiogram electrodes 31 are also electrically connected to a measurement data transmitter 65. Measurement data from the electrocardiogram electrodes 31 is input to the measurement data transmitter 65 and wirelessly transmitted from the measurement data transmitter 65 to the time interval detection unit 36 ​​in the display device 1 shown in Fig. 1.

[0016] As shown in Fig. 2, the photoplethysmographic detection sensor 32 is attached to a peripheral part of the subject, such as a finger, and measures, for example, the pulse wave. The pulse wave transit time (PWTT) is obtained from the measurement data obtained from the electrocardiogram electrodes 31 and the pulse wave obtained from the photoplethysmographic detection sensor 32. The photoplethysmographic detection sensor 32 is electrically connected to a measurement data transmitter 65. The measurement data obtained by the photoplethysmographic detection sensor 32 is input to the measurement data transmitter 65 and wirelessly transmitted from the measurement data transmitter 65 to the pulse wave detection unit 33 in the display device 1 shown in Fig. 1.

[0017] The respiration measuring device 4 continuously measures the respiration of the subject. The measurement data measured by the respiration measuring device 4 is input to the respiratory cycle detecting means 41 of the display device 1.

[0018] The invasive blood pressure measuring device 5 measures blood pressure by an invasive blood pressure (IBP) method, i.e., by inserting a catheter into the subject's blood vessel. Measurement data by the invasive blood pressure measuring device 5 is input to the invasive blood pressure pulse pressure measuring means 51 of the display device 1.

[0019] The reception unit 6 receives an input operation from the operator and generates an instruction signal corresponding to the input operation. The reception unit 6 is, for example, a touch panel placed on the display unit 71 (described later), operation buttons provided on the housing of the display device 1, or a mouse or keyboard connected to an input / output interface (e.g., a USB interface, etc.) not shown. The instruction signal generated by the reception unit 6 is input to the display device 1.

[0020] [Display device configuration] The display device 1 includes a pulse wave detection unit 33, an A / D converter 34, a time interval detection unit 36, a calculation unit 70, a display control unit 72, and a receiving unit 74. The calculation unit 70 includes an NIBP pulse pressure measurement means 11, a heart rate calculation means 12, a pulse wave transit time measurement means 13, a pulse wave transit time respiratory variation measurement means 14, a pulse wave amplitude measurement means 15, a pulse wave amplitude respiratory variation measurement means 16, a circulatory dynamics calculation means 17, an intrinsic coefficient calculation means 18, a memory unit 19, a respiratory cycle detection means 41, an invasive blood pressure pulse pressure measurement means 51, and a pulse pressure respiratory variation measurement means 52.

[0021] The time interval detection unit 36 ​​acquires an electrocardiogram waveform based on the measurement data received from the electrocardiogram electrodes 31 via the measurement data transmitter 65. The time interval detection unit 36 ​​also converts the measurement data into a digital signal and outputs it to the heart rate calculation means 12 and pulse wave transit time measurement means 13 of the calculation unit 70.

[0022] Pulse wave detection unit 33 acquires the waveform of the peripheral photoplethysmogram based on the measurement data received from photoplethysmogram sensor 32 via measurement data transmitter 65. Pulse wave detection unit 33 then outputs the measurement data to A / D converter 34. A / D converter 34 converts the measurement data into a digital signal and outputs it to pulse wave transit time measurement means 13 and pulse wave amplitude measurement means 15 of calculation unit 70.

[0023] The NIBP pulse pressure measuring means 11 measures the NIBP pulse pressure based on the blood pressure data measured by the blood pressure measuring device 2. The NIBP pulse pressure is calculated from the difference between the systolic (maximum) blood pressure value and the diastolic (minimum) blood pressure value. The measured NIBP pulse pressure is input to the intrinsic coefficient calculating means 18.

[0024] The heart rate calculation means 12 calculates the number of beats per minute (heart rate, HR) based on the reference point (time point at which the R wave occurs) measured by the time interval detection unit 36. The calculated heart rate HR is input to the circulatory dynamics calculation means 17.

[0025] The pulse wave transit time measuring means 13 calculates the pulse wave transit time PWTT, which is the time it takes for the R wave of the electrocardiogram to reach the peripheral SpO2 pulse wave, based on the reference point (the time when the R wave occurs) measured by the time interval detecting unit 36 ​​and the waveform of the peripheral part detected by the photoelectric pulse wave detecting sensor 32.

[0026] More specifically, the pulse wave transit time measurement means 13 calculates a moving average of multiple pulse wave transit times immediately preceding the current time to prevent the value of the pulse wave transit time PWTT from being disturbed by the influence of momentary noise, etc. Specifically, the pulse wave transit time measurement means 13 calculates 16 consecutive pulse wave transit times PWTT and then calculates the moving average of these 16 pulse wave transit times PWTT. Hereinafter, the moving average of the 16 pulse wave transit times PWTT will be referred to as the "moving average value PWTT-16."

[0027] Furthermore, the pulse wave transit time measurement means 13 calculates four consecutive moving average values ​​PWTT-16 using 64 consecutive pulse wave transit times PWTT, and then calculates the moving average value of these four moving average values ​​PWTT-16. The moving average value of the pulse wave transit time PWTT calculated in this way is referred to as the "moving average value PWTT-64." The pulse wave transit time measurement means 13 then outputs the calculated moving average value PWTT-64 as the pulse wave transit time PWTT to the circulatory dynamics calculation means 17 and the pulse wave transit time respiratory variation measurement means 14.

[0028] The pulse wave transit time respiratory variation measuring means 14 measures the respiratory variation of the pulse wave transit time PWTT based on the pulse wave transit time PWTT calculated by the pulse wave transit time measuring means 13 and the respiratory cycle detected by the respiratory cycle detecting means 41. The measurement data indicating the measured respiratory variation of the pulse wave transit time PWTT is input to the intrinsic coefficient calculating means 18.

[0029] Pulse wave amplitude measuring means 15 measures the amplitude of the pulse wave from the waveform of the peripheral part acquired by pulse wave detection unit 33. The measured pulse wave amplitude is input to pulse wave amplitude respiratory variation measuring means 16.

[0030] The respiratory cycle detection means 41 detects the respiratory cycle from the respiratory data measured by the respiration measurement device 4. The detected respiratory cycle is input to the pulse wave transit time respiratory variation measurement means 14, the pulse wave amplitude respiratory variation measurement means 16, and the pulse pressure respiratory variation measurement means 52.

[0031] Pulse wave amplitude respiratory variation measuring means 16 measures the respiratory variation of pulse wave amplitude (PAV: Pulse Amplitude Variation) based on the pulse wave amplitude measured by pulse wave amplitude measuring means 15 and the respiratory cycle detected by respiratory cycle detecting means 41. The measured respiratory variation of pulse wave amplitude is input to intrinsic coefficient calculating means 18.

[0032] The invasive blood pressure pulse pressure measuring means 51 measures the IBP pulse pressure based on the blood pressure data measured by the invasive blood pressure measuring device 5. The measured IBP pulse pressure is input to the pulse pressure respiratory variation measuring means 52.

[0033] The pulse pressure respiratory variation measuring means 52 measures the respiratory variation of pulse pressure (PPV: Pulse Pressure Variation) based on the IBP pulse pressure measured by the invasive blood pressure pulse pressure measuring means 51 and the respiratory cycle measured by the respiratory cycle detecting means 41. The measurement data indicating the measured respiratory variation of pulse pressure is input to the intrinsic coefficient calculating means 18.

[0034] The intrinsic coefficient calculation means 18 calculates coefficients intrinsic to the subject based on the NIBP pulse pressure measured by the NIBP pulse pressure measurement means 11, the respiratory variation in pulse wave transit time PWTT measured by the pulse wave amplitude respiratory variation measurement means 14, the respiratory variation in pulse wave amplitude measured by the pulse wave amplitude respiratory variation measurement means 16, and the respiratory variation in pulse pressure measured by the pulse pressure respiratory variation measurement means 52. The calculated coefficients are, for example, coefficients K, α, and β, which will be described later, and are input to the circulatory dynamics calculation means 17.

[0035] The circulatory dynamics calculation means 17 calculates the subject's circulatory dynamics parameters based on the heart rate HR calculated by the heart rate calculation means 12, the pulse wave transit time PWTT measured by the pulse wave transit time measurement means 13, and the coefficients K, α, and β calculated by the characteristic coefficient calculation means 18.

[0036] Here, the circulatory dynamics calculation means 17 calculates the flow rate of blood flowing into the aorta during cardiac systole (stroke volume, SV) and the cardiac output measured non-invasively and continuously (estimated continuous cardiac output, esCCO) as circulatory dynamics parameters.

[0037] Furthermore, the circulatory dynamics calculation means 17 calculates the rate of change of the circulatory dynamics parameters during a period in which the subject is receiving treatment such as infusion or medication (hereinafter referred to as the "treatment period"). The calculation of the circulatory dynamics parameters by the circulatory dynamics calculation means 17 and the calculation of the rate of change of the circulatory dynamics parameters will be described later.

[0038] [Calculation of hemodynamic parameters and rate of change in hemodynamic parameters] (Calculation of circulatory dynamics parameters) There is a correlation between stroke volume SV and pulse wave transit time PWTT as shown in Equation 1. In Equation 1, K, α, and β are coefficients specific to each subject. SV = K * (α * PWTT + β) (Equation 1)

[0039] The circulatory dynamics calculation means 17 substitutes the coefficients K, α, and β calculated by the intrinsic coefficient calculation means 18 into Equation 1. Furthermore, the circulatory dynamics calculation means 17 substitutes, for example, the moving average value PWTT-64 received from the pulse wave transit time measurement means 13 into PWTT in Equation 1. In this way, the circulatory dynamics calculation means 17 can calculate the stroke volume SV. The stroke volume SV calculated by the circulatory dynamics calculation means 17 will be referred to as the "stroke volume esSV" hereinafter.

[0040] The circulatory dynamics calculation means 17 periodically calculates the stroke volume esSV, and stores the calculated stroke volume esSV in the storage unit 19 in association with the timing of calculation, for example.

[0041] Furthermore, when the amount of blood ejected by the beating of the heart (cardiac output, CO) is used, there is a correlation between the stroke volume SV and the heart rate HR as shown in Equation 2. SV = CO / HR (Equation 2)

[0042] Using Equations 1 and 2, the noninvasive continuous estimated cardiac output (esCCO) can be calculated as shown in Equation 3 below. CO=SV*HR =K*(α*PWTT+β)*HR =esCCO (Equation 3)

[0043] The circulatory dynamics calculation means 17 substitutes the coefficients K, α, and β into Equation 3. The circulatory dynamics calculation means 17 also substitutes the moving average value PWTT-64 for PWTT in Equation 3. This allows the circulatory dynamics calculation means 17 to calculate the noninvasive continuous estimated cardiac output esCCO.

[0044] The circulatory dynamics calculation means 17 periodically calculates the noninvasive continuous estimated cardiac output esCCO, and stores the calculated noninvasive continuous estimated cardiac output esCCO in the storage unit 19 in association with the calculation timing, for example.

[0045] (Calculation of the rate of change of hemodynamic parameters) An operator who performs a treatment on a subject can input the start timing of the treatment to the bio-information processing device M by performing a predetermined input operation on the reception unit 6. When such an input operation is performed, the reception unit 6 outputs a start signal indicating the content of the input operation and the start timing to the display device 1.

[0046] Furthermore, the operator can input the timing for ending the treatment to the bio-information processing device M by performing a predetermined input operation on the reception unit 6. When such an input operation is performed, the reception unit 6 outputs an end signal indicating the end timing to the display device 1.

[0047] When the receiving unit 74 of the display device 1 receives the start signal or the end signal output from the accepting unit 6, it outputs the received start signal or the end signal to the calculating unit 70 and the display control unit 72.

[0048] When the circulatory dynamics calculation means 17 of the calculation unit 70 receives a start signal from the receiving unit 74, it stores the start timing indicated by the start signal in the storage unit 19. Furthermore, when the circulatory dynamics calculation means 17 receives an end signal from the receiving unit 74, it stores the end timing indicated by the end signal in the storage unit 19.

[0049] After receiving the end signal, the circulatory dynamics calculation means 17 identifies the treatment period based on the start timing and end timing, and calculates the rate of change of the circulatory dynamics parameters during the identified treatment period.

[0050] For example, the circulatory dynamics calculation means 17 refers to a plurality of noninvasive continuous estimated cardiac outputs esCCO stored in the memory unit 19 and identifies the maximum value esCCOmax of the noninvasive continuous estimated cardiac outputs esCCO calculated during the treatment period and the minimum value esCCOmin of the noninvasive continuous estimated cardiac outputs esCCO calculated during the treatment period.

[0051] Then, by using the maximum value esCCOmax and the minimum value esCCOmin, the circulatory dynamics calculation means 17 can calculate the rate of change of the noninvasive continuous estimated cardiac output esCCO according to the following equation 4. The circulatory dynamics calculation means 17 stores the calculated rate of change in the memory unit 19. Rate of change of esCCO = 2 * (esCCOmax - esCCOmin) / (esCCOmax + esCCOmin) (Equation 4)

[0052] In addition, the circulatory dynamics calculation means 17 refers to the multiple stroke volumes esSV stored in the memory unit 19 and identifies the maximum value esSVmax of the stroke volumes esSV calculated during the treatment period and the minimum value esSVmin of the stroke volumes esSV calculated during the treatment period.

[0053] Then, by using the maximum value esSVmax and the minimum value esSVmin, the circulatory dynamics calculation means 17 can calculate the rate of change of the stroke volume esSV as shown in the following equation 5. The circulatory dynamics calculation means 17 stores the calculated rate of change in the storage unit 19. esSV change rate = 2 * (esSVmax - esSVmin) / (esSVmax + esSVmin) (Equation 5)

[0054] The start signal from the accepting unit 6 may be a signal that does not include information about the start timing. In this case, for example, the receiving unit 74 notifies the calculation unit 70 and the display control unit 72 of the reception timing of the start signal as the start timing. Similarly, for the end signal, if the end signal is a signal that does not include information about the end timing, the receiving unit 74 notifies the calculation unit 70 and the display control unit 72 of the reception timing of the end signal as the end timing.

[0055] [Display control processing] (Display of hemodynamic parameters and rate of change of hemodynamic parameters) (a) Display during periods when no treatment has been performed The display control unit 72 controls output of the circulatory dynamics parameters and the change rates of the circulatory dynamics parameters calculated by the circulatory dynamics calculation means 17 to a display unit 71 such as a monitor. As a result, a screen including the circulatory dynamics parameters and the change rates of the circulatory dynamics parameters is displayed on the display unit 71. Fig. 3 is a diagram showing an example of a screen displayed on the display unit 71 shown in Fig. 1.

[0056] 3, the screen displayed on the display unit 71 displays the subject's current heart rate, blood pressure, noninvasive continuous estimated cardiac output esCCO, stroke volume esSV, etc. The screen also includes an area R that displays the subject's hemodynamic parameters during the treatment period.

[0057] The region R includes multiple tabs Tb. These multiple tabs Tb include, for example, a tab Tb1 for selecting a display related to hemodynamic parameters, and a tab Tb2 for selecting a display related to the rate of change of the hemodynamic parameters. The tab Tb1 is labeled, for example, "esCCO." The tab Tb2 is labeled, for example, "rate of change calculation."

[0058] Figure 3 shows the screen that is displayed when an operator selects tab Tb1 and then performs an input operation to select tab Tb2 on the reception unit 6 shown in Figure 1, during a period when no treatment is being performed on the subject.

[0059] When the above-described input operation is performed, the reception unit 6 outputs an instruction signal indicating the content of the input operation to the reception unit 74 of the display device 1. When the reception unit 74 receives the instruction signal output from the reception unit 6, it outputs the instruction signal to the display control unit 72.

[0060] When the display control unit 72 receives the instruction signal output from the receiving unit 74, it reads out the start timing and end timing stored in the storage unit 19 and specifies one or more treatment periods for the subject.

[0061] Furthermore, the display control unit 72 refers to the multiple circulatory dynamics parameters and the rates of change of the multiple circulatory dynamics parameters stored in the storage unit 19, and reads out, for each treatment period, the start timing, the end timing, the circulatory dynamics parameters associated with the start timing, the circulatory dynamics parameters associated with the end timing, and the rates of change of the circulatory dynamics parameters from the storage unit 19. Then, the display control unit 72 performs control so that these read values ​​are displayed in the region R.

[0062] Furthermore, the display control unit 72 can switch between displaying the rate of change in the noninvasive continuous estimated cardiac output esCCO and the rate of change in the stroke volume esSV as the rate of change display of the hemodynamic parameter.

[0063] More specifically, when tab Tb1 or Tb2 is selected, area R includes a selection button B11 for selecting the display of noninvasive continuous estimated cardiac output esCCO, a selection button B12 for selecting the display of stroke volume esSV, and a table Ta showing a list of the rates of change of hemodynamic parameters for each treatment period. Selection button B11 is labeled, for example, "ΔesCCO." Selection button B12 is labeled, for example, "ΔesSV."

[0064] The operator can select either selection button B11 or selection button B12. When the operator does not select either selection button B11 or selection button B12, selection button B11 is automatically selected. In other words, in this state, table Ta displays the noninvasive continuous estimated cardiac output esCCO and the rate of change of the noninvasive continuous estimated cardiac output esCCO.

[0065] Specifically, suppose the subject received the first treatment between 15:30 and 15:45, and the second treatment between 15:48 and 15:58.

[0066] In this case, for example, Table Ta displays that the noninvasive continuous estimated cardiac output esCCO at 15:30 is 5.00, the noninvasive continuous estimated cardiac output esCCO at 15:45 is 5.08, and the rate of change in noninvasive continuous estimated cardiac output esCCO during the first treatment period is 12%. Table Ta also displays that the noninvasive continuous estimated cardiac output esCCO at 15:48 is 5.10, the noninvasive continuous estimated cardiac output esCCO at 15:58 is 5.20, and the rate of change in noninvasive continuous estimated cardiac output esCCO during the second treatment period is 10%.

[0067] In table Ta, for example, the most recent treatment duration value is displayed in the top row, so if two treatments have been performed, the value for the second treatment duration is displayed in the first row, and the value for the first treatment duration is displayed in the second row.

[0068] Also, assume that the operator performs an input operation to select selection button B12 included in region R. In this case, the display control unit 72 performs control so that the stroke volume esSV and the rate of change in stroke volume esSV for each treatment period are displayed in table Ta, instead of the noninvasive continuous estimated cardiac output esCCO and the rate of change in noninvasive continuous estimated cardiac output esCCO for each treatment period.

[0069] If any of the change rates of the hemodynamic parameters displayed in the table Ta is less than a predetermined threshold, the display control unit 72 may perform control so that the display is performed in a way that makes it easier for the operator to recognize that the change rate is less than the threshold. For example, the display control unit 72 may perform control so that the color of the change rate is displayed in a different color from the colors of the other change rates, or so that a message indicating that the change rate is less than the threshold is displayed on the screen.

[0070] (b) Display during treatment period Region R further includes a selection button B13 for inputting the start and end timings of the treatment. For example, the selection button B13 is marked with the words "before treatment" during a period when no treatment is being performed, and "after treatment" during a treatment period.

[0071] As described above, the operator can input the start and end timings of the treatment into the bio-information processing device M by performing a predetermined input operation on the reception unit 6. This predetermined input operation is, for example, an operation of selecting the selection button B13 displayed in the region R.

[0072] That is, at the start timing of the treatment, the worker performs an operation to select the selection button B13 marked with the characters "before implementation." As a result, the start timing is input to the biometric information processing device M, and the characters on the selection button B13 change to "after implementation." Furthermore, at the end timing of the treatment, the worker performs an operation to select the selection button B13 marked with the characters "after implementation." As a result, the end timing is input to the biometric information processing device M, and the characters on the selection button B13 change to "before implementation."

[0073] Fig. 4 is a diagram showing an example of a screen displayed when a new treatment for a subject is started. With reference to Fig. 3 and Fig. 4, for example, it is assumed that the operator performs an input operation to the reception unit 6 to select the selection button B13 shown in Fig. 3 at 4:00 pm, which is the timing to start a new treatment for the subject.

[0074] In this case, the accepting unit 6 outputs an instruction signal indicating the content of the input operation and the start timing, 4:00 p.m., as a start signal to the receiving unit 74 of the display device 1. Upon receiving the instruction signal output from the accepting unit 6, the receiving unit 74 outputs the instruction signal to the calculating unit 70 and the display control unit 72.

[0075] When the circulatory dynamics calculation means 17 in the calculation unit 70 receives the instruction signal output from the receiving unit 74, it stores 16:00 indicated by the instruction signal in the storage unit 19 as the start timing.

[0076] When the display control unit 72 receives the instruction signal output from the receiving unit 74, it controls so that the text attached to the selection button B13 on the screen changes from "Before Implementation" to "After Implementation." The display control unit 72 also references a plurality of circulatory dynamics parameters stored in the storage unit 19 and reads out the circulatory dynamics parameters corresponding to the start timing, 4:00 p.m., from the storage unit 19. The display control unit 72 then controls so that the start timing and the values ​​of the read circulatory dynamics parameters are displayed in the table Ta.

[0077] Specifically, the display control unit 72 controls the display so that the value of the circulatory dynamics parameter at 4:00 PM, which is the start timing of the latest treatment, and the value at 4:00 PM are displayed in the first row of the table Ta. The display control unit 72 also controls the display so that the values ​​for the treatment period from 3:48 PM to 3:58 PM, which were displayed in the first row in Fig. 3, are displayed in the second row, and the values ​​for the treatment period from 3:30 PM to 3:45 PM, which were displayed in the second row in Fig. 3, are displayed in the third row.

[0078] (c) Display of circulatory dynamics parameters at the current time As described above, the subject's current noninvasive continuous estimated cardiac output esCCO and stroke volume esSV are displayed on the screen displayed on display unit 71. Display control unit 72 periodically reads the latest noninvasive continuous estimated cardiac output esCCO and stroke volume esSV stored in memory unit 19 and outputs the read noninvasive continuous estimated cardiac output esCCO and stroke volume esSV to display unit 71.

[0079] As an example, the screen shown in FIG. 4 displays the noninvasive continuous estimated cardiac output esCCO at the current time, which is "3.73," and the stroke volume esSV at the current time, which is "47."

[0080] Although the screens shown in FIGS. 3 and 4 display both the noninvasive continuous estimated cardiac output esCCO and the stroke volume esSV as the subject's current hemodynamic parameters, the screen may be configured to display either the noninvasive continuous estimated cardiac output esCCO or the stroke volume esSV.

[0081] (Switching of moving average value of pulse wave transit time (PWTT) used to calculate hemodynamic parameters) Here, if the heart rate HR is 80 bpm, it takes about one minute to calculate the moving average value PWTT-64 of 64 pulse wave transit times PWTT. However, during certain periods, such as during treatment, it may be necessary to monitor sudden changes in the subject's hemodynamics.

[0082] For this reason, the bioinformation processing device M is configured to be able to switch, for example, the moving average value of the pulse wave propagation time PWTT used to calculate circulatory dynamics parameters between the moving average value PWTT-64 of the pulse wave propagation time PWTT for 64 times (the first pulse wave propagation time) and the moving average value PWTT-16 of the pulse wave propagation time PWTT for 16 times (the second pulse wave propagation time).

[0083] (a) Automatic switching 1, during a period when no treatment is being performed, i.e., a period when no start signal is received from the receiving unit 74, the pulse wave transit time measuring means 13 outputs the moving average value PWTT-64 as the pulse wave transit time PWTT to the circulatory dynamics calculating means 17. This allows the circulatory dynamics calculating means 17 to calculate circulatory dynamics parameters using the highly accurate moving average value PWTT-64, with the effects of noise and the like reduced.

[0084] That is, during periods when no treatment is being performed, the current noninvasive continuous estimated cardiac output esCCO and stroke volume esSV are displayed using the moving average PWTT-64 on display unit 71. This allows the operator to more accurately check changes in the noninvasive continuous estimated cardiac output esCCO and stroke volume esSV.

[0085] On the other hand, during the treatment period, i.e., the period after receiving the start signal from the receiving unit 74 but before receiving the end signal from the receiving unit 74, the pulse wave transit time measuring means 13 outputs the moving average value PWTT-16 as the pulse wave transit time PWTT to the circulatory dynamics calculating means 17. This allows the circulatory dynamics calculating means 17 to calculate circulatory dynamics parameters using the moving average value PWTT-16 calculated earlier.

[0086] That is, during the treatment period, the current noninvasive continuous estimated cardiac output esCCO and stroke volume esSV are frequently updated on the display unit 71. This allows the operator to quickly check changes in the noninvasive continuous estimated cardiac output esCCO and stroke volume esSV.

[0087] (b) Manual switching The pulse wave transit time measuring means 13 may switch the moving average value to be output as the pulse wave transit time PWTT to the circulatory dynamics calculating means 17 between the moving average value PWTT-64 and the moving average value PWTT-16 when a specified input operation is performed by the operator, regardless of whether or not it is a treatment period.

[0088] 5 is a diagram illustrating an operation for instructing switching of the pulse wave transit time PWTT used in calculating hemodynamic parameters. As shown in FIG. 5, the plurality of tabs Tb included in the area R includes a tab Tb3 for selecting the display of a setting screen related to hemodynamic parameters. The tab Tb3 is labeled, for example, "Advanced Settings."

[0089] 5 shows a screen when an operator performs an input operation on the reception unit 6 shown in FIG. 1 to select tab Tb1 and then tab Tb3. When the above-described input operation is performed, the reception unit 6 outputs an instruction signal indicating the content of the input operation to the reception unit 74 of the display device 1. When the reception unit 74 receives the instruction signal output from the reception unit 6, it outputs the instruction signal to the display control unit 72.

[0090] When the display control unit 72 receives the instruction signal output from the receiving unit 74, it controls the display unit 71 to display a setting screen related to circulatory dynamics parameters, as shown in Fig. 5, based on the instruction signal. The setting screen displays selection buttons B21 and B22 for selecting the pulse wave transit time PWTT used to calculate the circulatory dynamics parameters. The selection button B21 is labeled, for example, "Normal." The selection button B22 is labeled, for example, "Quick."

[0091] It is assumed that the worker performs an input operation to select the selection button B21 on the reception unit 6. When the above-described input operation is performed, the reception unit 6 outputs an instruction signal indicating the content of the input operation to the reception unit 74 of the display device 1. When the reception unit 74 receives the instruction signal output from the reception unit 6, it outputs the instruction signal to the calculation unit 70.

[0092] When the pulse wave transit time measuring means 13 of the calculation unit 70 receives an instruction signal indicating that the selection button B21 has been selected, it outputs the moving average value PWTT-64 as the pulse wave transit time PWTT to the circulatory dynamics calculation means 17. The circulatory dynamics calculation means 17 uses the moving average value PWTT-64 to calculate circulatory dynamics parameters.

[0093] Furthermore, suppose that the worker performs an input operation to select selection button B22 on the reception unit 6. When the above-described input operation is performed, the reception unit 6 outputs an instruction signal indicating the content of the input operation to the reception unit 74 of the display device 1. When the reception unit 74 receives the instruction signal output from the reception unit 6, it outputs the instruction signal to the calculation unit 70.

[0094] When the pulse wave transit time measuring means 13 of the calculation unit 70 receives an instruction signal indicating that the selection button B22 has been selected, it switches the moving average value output as the pulse wave transit time PWTT to the circulatory dynamics calculation means 17 from the moving average value PWTT-64 to the moving average value PWTT-16. Then, the circulatory dynamics calculation means 17 calculates circulatory dynamics parameters using the moving average value PWTT-16.

[0095] In addition, when the operator does not select either the selection button B21 or the selection button B22, the selection button B21 is automatically selected. Therefore, in this state, the circulatory dynamics calculation means 17 calculates the circulatory dynamics parameters using the moving average value PWTT-64.

[0096] Furthermore, the moving average value of the pulse wave transit time PWTT that can be used to calculate circulatory dynamics parameters is not limited to being switchable between two types, the moving average value PWTT-16 and the moving average value PWTT-64, but may be switchable between three or more types of moving average values.

[0097] In addition, even when tab Tb2 for selecting a display regarding the rate of change of circulatory dynamics parameters is selected, the pulse wave transit time measuring means 13 may switch the moving average value to be output to the circulatory dynamics calculation means 17 from the moving average value PWTT-64 to the moving average value PWTT-16.

[0098] In addition, the biological information display device including the circulatory dynamics calculation means 17, the intrinsic coefficient calculation means 18, the memory unit 19, the display unit 71, the display control unit 72, and the receiving unit 74 in the calculation unit 70 may be provided separately from the processing device including the other components in the calculation unit 70.

[0099] The display unit 71 may be provided inside the display device 1. When the biometric information display device is provided separately from the processing device as described above, the display unit 71 may be provided inside the biometric information display device.

[0100] [Operation flow] FIG. 6 is a flowchart illustrating the flow of an operation for switching the pulse wave transit time PWTT used for calculating circulatory dynamics parameters in the biological information processing device M according to the embodiment of the present disclosure.

[0101] 6, for example, when an operator starts up the display device 1, each means in the calculation unit 70 performs measurement, etc. At this time, the pulse wave transit time measurement means 13 outputs the moving average value PWTT-64 as the pulse wave transit time PWTT to the circulatory dynamics calculation means 17, and the circulatory dynamics calculation means 17 calculates circulatory dynamics parameters using the moving average value PWTT-64. Then, the circulatory dynamics parameters calculated by the circulatory dynamics calculation means 17 are displayed on the display unit 71 (step S10).

[0102] Next, if treatment has not started on the subject, i.e., if the operator has not performed an input operation for the start timing of treatment, or if the operator has not performed an operation to select selection button B22 shown in Figure 5 ("NO" in step S11), the operation shown in step S10 continues.

[0103] On the other hand, when treatment for the subject is started, that is, when the operator inputs the timing of starting treatment, or when the operator selects the selection button B22 shown in FIG. 5 ("YES" in step S11), the pulse wave transit time measurement means 13 switches the moving average value output to the circulatory dynamics calculation means 17 as the pulse wave transit time PWTT from the moving average value PWTT-64 to the moving average value PWTT-16. The circulatory dynamics calculation means 17 then calculates circulatory dynamics parameters using the moving average value PWTT-16, and the circulatory dynamics parameters calculated by the circulatory dynamics calculation means 17 are displayed on the display unit 71 (step S12).

[0104] Next, if the treatment for the subject has not been completed, i.e., if the operator has not performed an input operation for the timing of the end of the treatment, or if the operator has not performed an operation to select the selection button B21 shown in Figure 5 ("NO" in step S13), the operation shown in step S12 continues.

[0105] On the other hand, when the treatment for the subject is completed, that is, when the operator inputs the timing of the treatment completion, or when the operator selects the selection button B21 shown in Fig. 5 ("YES" in step S13), the operation shown in step S10 is performed again. These operations from step S10 to step S13 are repeated until, for example, the operator stops the bio-information processing device M.

[0106] As described above, in the biological information processing device M according to one embodiment of the present disclosure, the receiving unit 74 receives a start signal indicating the start timing of a treatment for a subject and an end signal indicating the end timing of the treatment. The calculating unit 70 calculates a moving average value of the subject's pulse wave transit time PWTT, calculates the subject's hemodynamic parameters using the calculated moving average value, and further calculates a rate of change of the hemodynamic parameters during the treatment period from the start timing to the end timing based on the start signal and the end signal received by the receiving unit 74. The display control unit 72 then controls the display unit 71 to output the calculated rate of change.

[0107] In this way, by automatically calculating and displaying the rate of change of the circulatory dynamics parameter, it is possible to easily visually confirm the change in the circulatory dynamics of the subject during the treatment period. Furthermore, by calculating the circulatory dynamics parameter using a moving average value over multiple pulse wave transit times, it is possible to display a more accurate value that is free from the influence of noise, etc.

[0108] In addition, in the biological information processing device M according to another aspect of the present disclosure, the display control unit 72 can switch between displaying the rate of change in stroke volume esSV and displaying the rate of change in noninvasive continuous estimated cardiac output esCCO. With this configuration, the operator can arbitrarily select and check either the rate of change in stroke volume esSV or the rate of change in noninvasive continuous estimated cardiac output esCCO.

[0109] Furthermore, in the biological information processing device M according to another aspect of the present disclosure, the display control unit 72 further controls the display unit 71 to output the circulatory dynamics parameters calculated by the calculation unit 70 using moving average values ​​for a plurality of pulse wave propagation times immediately preceding the current time. With this configuration, it is possible to quickly check not only the rate of change in the circulatory dynamics parameters during the treatment period but also the circulatory dynamics parameters themselves.

[0110] Furthermore, in the biological information processing device M according to another aspect of the present disclosure, the display control unit 72 further controls the display unit 71 to output circulatory dynamics parameters calculated using the moving average values ​​for a plurality of pulse wave propagation times immediately before the start timing, the end timing, and the start timing of the treatment, and circulatory dynamics parameters calculated using the moving average values ​​for a plurality of pulse wave propagation times immediately before the end timing. With this configuration, it is possible to check the circulatory dynamics parameters at the start timing and the end timing of the treatment for the subject.

[0111] Furthermore, in the biological information processing device M according to another aspect of the present disclosure, the display control unit 72 performs control to output a list of change rates of multiple treatments to the display unit 71 based on the start signal and end signal received by the receiving unit 74. With this configuration, it is possible to compare changes in hemodynamics in multiple treatments.

[0112] In addition, in a biological information processing device M according to another aspect of the present disclosure, the calculation unit 70 calculates a moving average value of the pulse wave transit time PWTT of the subject and calculates a circulatory dynamics parameter of the subject using the calculated moving average value. The calculation unit 70 can switch the calculation target between a circulatory dynamics parameter using a moving average value PWTT-64 for a first pulse wave transit time and a circulatory dynamics parameter using a moving average value PWTT-16 for a second pulse wave transit time that is shorter than the first pulse wave transit time.

[0113] With this configuration, for example, in a situation where changes in the subject's circulatory dynamics need to be confirmed early, the circulatory dynamics parameters can be calculated using the moving average value PWTT-16 for the second pulse wave transit time, and in a situation where changes in the circulatory dynamics need to be confirmed with high accuracy while reducing the influence of noise, etc., the circulatory dynamics parameters can be calculated using the moving average value PWTT-64 for the first pulse wave transit time. Therefore, the subject's biological information can be processed in a more appropriate manner depending on the usage situation.

[0114] In addition, in a biological information processing device M according to another embodiment of the present disclosure, the receiving unit 74 receives a start signal indicating the start timing of a treatment for a subject and an end signal indicating the end timing of the treatment. The calculating unit 70 calculates circulatory dynamics parameters using the moving average value PWTT-64 when no treatment is being performed, and calculates circulatory dynamics parameters using the moving average value PWTT-16 during the treatment period, based on the start signal and the end signal received by the receiving unit 74.

[0115] In this way, while the subject is receiving treatment, hemodynamic parameters are calculated using the moving average value PWTT-16 for the second pulse wave transit time, which is calculated early, allowing changes in hemodynamics to be quickly confirmed.On the other hand, while no treatment is being performed, hemodynamic parameters are calculated using the moving average value PWTT-64 for the first pulse wave transit time, which is highly accurate as the effects of noise, etc. are reduced, allowing changes in hemodynamics to be confirmed more accurately.

[0116] In addition, in the biological information processing device M according to another aspect of the present disclosure, when the accepting unit 6, which accepts operations by an operator, accepts a predetermined operation, the calculation unit 70 switches the calculation target from the circulatory dynamics parameters using the moving average value PWTT-64 to the circulatory dynamics parameters using the moving average value PWTT-16. With this configuration, the calculation target can be switched between the circulatory dynamics parameters using the moving average value PWTT-64 and the circulatory dynamics parameters using the moving average value PWTT-16 at any timing desired by the operator.

[0117] Although the embodiments of the present disclosure have been described above, the technical scope of the present application should not be construed as being limited by the description of the present embodiments. The present embodiments are merely examples, and it will be understood by those skilled in the art that various modifications of the embodiments are possible within the scope of the invention described in the claims. The technical scope of the present application should be determined based on the scope of the invention described in the claims and its equivalents. [Explanation of symbols]

[0118] M: biological information processing device (biological information display device), 1: display device, 2: blood pressure measuring device, 4: respiration measuring device, 5: invasive blood pressure measuring device, 6: reception unit, 11: NIBP pulse pressure measuring means, 12: heart rate calculating means, 13: pulse wave transit time measuring means, 14: pulse wave transit time respiratory variation measuring means, 15: pulse wave amplitude measuring means, 16: pulse wave amplitude respiratory variation measuring means, 17: circulatory dynamics calculating means, 18: intrinsic coefficient calculating means, 19: memory unit, 41: respiratory cycle detecting means, 51: invasive blood pressure pulse pressure measuring means, 52: pulse pressure respiratory variation measuring means, 71: display unit, 72: display control unit, 74: receiving unit

Claims

1. a receiving unit that receives a start signal indicating a timing to start a treatment on a subject and an end signal indicating a timing to end the treatment; a calculation unit that calculates a moving average value of a pulse wave transit time of the subject, calculates a circulatory dynamics parameter of the subject using the calculated moving average value, identifies a treatment period during which the treatment is being performed based on the start signal and the end signal received by the receiving unit, and calculates a rate of change of the circulatory dynamics parameter during the treatment period using a maximum value and a minimum value of the circulatory dynamics parameter; a display control unit that controls output of the calculated rate of change to a display unit.

2. The biological information display device according to claim 1 , wherein the display control unit is capable of switching between displaying a rate of change in stroke volume and displaying a rate of change in cardiac output as the rate of change display.

3. 3. The biological information display device according to claim 1, wherein the display control unit further controls the display unit to output the circulatory dynamics parameter calculated by the calculation unit using the moving average value for a plurality of pulse wave propagation times immediately preceding the current time.

4. 3. The biological information display device according to claim 1, wherein the display control unit further controls outputting to the display unit the circulatory dynamics parameters calculated by the calculation unit using the moving average values ​​for the start timing, the end timing, and a plurality of pulse wave propagation times immediately preceding the start timing, and the circulatory dynamics parameters calculated by the calculation unit using the moving average values ​​for a plurality of pulse wave propagation times immediately preceding the end timing.

5. 3. The biological information display device according to claim 1, wherein the display control unit controls outputting a list of the change rates for each of the multiple treatment periods to the display unit based on the start signal and the end signal received by the receiving unit.

6. receiving an initiation signal indicating when treatment should begin for the subject; receiving an end signal indicating the timing to end the treatment; calculating a moving average value of the pulse wave transit time of the subject, and calculating a circulatory dynamics parameter of the subject using the calculated moving average value; specifying a treatment period during which the treatment is being performed based on the start signal and the end signal, and calculating a rate of change of the hemodynamic parameter during the treatment period using a maximum value and a minimum value of the hemodynamic parameter during the treatment period; and performing control to output the calculated rate of change to a display unit.

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