Biometric information monitor and method of operating the biological information monitor

Abstract

To provide a biological information monitor that can reduce burden on a doctor when administering anesthetics, and a display method for the biological information monitor.SOLUTION: A biological information monitor includes: a corrected MAC (Minimum Alveolar Concentration) acquisition unit that acquires corrected MAC that has been corrected based on factors affecting effectiveness of an anesthetic drug; and a display unit that displays a list of corrected MACs for a plurality of anesthetic drugs acquired by the corrected MAC acquisition unit.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a biological information monitor and a method for displaying biological information, and particularly to a biological information monitor capable of displaying MAC (Minimum Alveolar Concentration) and a method for displaying biological information on the monitor.

Background Art

[0002] Conventionally, some biological information monitors are capable of connecting an exhaled gas sensor. This type of biological information monitor can display the gas concentration (e.g., the gas concentration of volatile anesthetics, oxygen, carbon dioxide, etc.) contained in the exhaled gas of a patient detected by the exhaled gas sensor. This type of biological information monitor is described in, for example, Patent Document 1.

[0003] Such a biological information monitor is used, for example, by an anesthesiologist during surgery. The anesthesiologist can judge the effectiveness of anesthesia on the patient based on the gas concentration displayed on the biological information monitor.

[0004] As standardized in Non-Patent Document 1, MAC is used as an index representing the effectiveness of anesthesia on a patient. MAC is the minimum alveolar concentration of an anesthetic at 1 atmosphere for making 50% of adult patients in a stationary state (a state without body movement reaction), and the numerical value of MAC = 1.0 is an index indicating that anesthesia is effective for 50% of adults. Surgically, an inhaled anesthetic concentration of 1.2 to 1.5 times the MAC value is required. For example, when MAC = 1.​​​​​​​​​​​​In equation (1), ExN2O is the N2O concentration (%) in exhaled breath, ExPAGT is the primary anesthetic gas concentration (%) in exhaled breath, and ExSAGT is the secondary anesthetic gas concentration (%) in exhaled breath. Also, KN2O is a constant for N2O, KPAGT is a constant for the primary anesthetic gas, and KSAGT is a constant for the secondary anesthetic gas. Incidentally, AGT is a general term for anesthetic gases.

[0007] Total MAC is the sum of the MAC values ​​for each inhaled anesthetic used in the calculation. Generally, the MAC displayed on the vital signs monitor screen is this Total MAC. Primary anesthetic gas is the main component of the anesthetic gas, in other words, the anesthetic gas with the highest concentration among the detected anesthetic gases. Secondary anesthetic gas is a minor component of the anesthetic gas, in other words, the anesthetic gas with the second highest concentration among the detected anesthetic gases. Equation (1) calculates Total MAC using the 1st and 2nd highest concentration anesthetic gases, but of course, Total MAC can also be calculated by including the 3rd and subsequent highest concentration anesthetic gases.

[0008] The constants KN2O, KPAGT, and KSAGT for each anesthetic gas are predetermined values. Examples of constants for each anesthetic gas are shown in Table 1 below.

[0009] [Table 1] Note that the value of this constant can be changed. In practice, the constants exemplified in Table 1 are slightly modified depending on the model, the doctor's judgment, etc.

[0010] Furthermore, the standard in Non-Patent Document 1 explicitly states that MAC may vary depending on the patient's age, and suggests that it should be appropriately adjusted according to age.

[0011] Furthermore, Non-Patent Document 2 proposes multiplying the calculated MAC by a correction formula, and many biometric monitors have been using this correction formula for some time. [Prior art documents] [Patent Documents]

[0012] [Patent Document 1] Special Publication No. 2010-508523 [Non-patent literature]

[0013] [Non-Patent Document 1] ISO-80601-2-55 : 2018 [Non-Patent Document 2] “Age-related iso-MAC charts for isoflurane, sevoflurane and desflurane in man”, British Journal of AnaesthesiaVol.91 Issue 2 p170-174 Published in issue: August, 2003, RWD Nickalls WW Mapleson [Overview of the project] [Problems that the invention aims to solve]

[0014] As mentioned above, by displaying MAC values ​​corrected for age on the vital signs monitor, medical professionals such as doctors can more accurately determine how well the anesthesia is working in the patient based on the corrected MAC values.

[0015] Incidentally, generally speaking, vital signs monitors capable of displaying MAC values ​​are equipped with a function to display not only the MAC value calculated based on the concentration of anesthetic in exhaled gas, but also the gas concentration value corresponding to MAC=1.0 for each anesthetic.

[0016] Medical staff can recognize how effective the anesthesia is for a patient based on the MAC value (i.e., Total MAC exemplified in Equation (1)) calculated based on the concentration of anesthetic in the exhaled gas displayed on the biological information monitor.

[0017] On the other hand, medical staff can determine the concentration of anesthetic to be administered to the patient from now on, using as an index the value of the gas concentration corresponding to MAC = 1.0 of each anesthetic displayed on the biological information monitor.

[0018] By the way, generally, the anesthetic administered to a patient is not of one type, and often a plurality of anesthetics are mixed and administered. Therefore, the doctor must determine the concentrations of a plurality of anesthetics to be administered to the patient, taking into account the MAC of each anesthetic and further considering that the concentration of the anesthetic corresponding to MAC = 1.0 changes according to factors such as the patient's age, etc., and complicated calculations are required.

[0019] The present invention has been made in consideration of the above points, and provides a biological information monitor and a display method of the biological information monitor that can reduce the burden on a doctor when administering anesthetic.

Means for Solving the Problems

[0020] One aspect of the biological information monitor of the present invention is a corrected MAC (Minimum Alveolar Concentration) acquisition unit that acquires a corrected MAC corrected based on factors affecting the effectiveness of each of a plurality of anesthetics, a display unit that displays a list of the corrected MACs for each of the plurality of anesthetics acquired by the corrected MAC acquisition unit, and is provided with.

[0021] One aspect of the display method of the biological information monitor of the present invention is For each of a plurality of anesthetics, a corrected MAC (Minimum Alveolar Concentration) acquisition step of acquiring a corrected MAC corrected based on factors affecting the effectiveness of the anesthetic, a display step of displaying a list of the corrected MACs for each of the plurality of anesthetics acquired in the corrected MAC acquisition step, is included.

Effect of the Invention

[0022] According to the present invention, since the concentrations of each anesthetic corrected according to factors affecting the effectiveness of the anesthetic are displayed in a list, a doctor can easily determine the concentrations of a plurality of anesthetics to be administered to a patient by looking at this list display. As a result, it is possible to realize a biological information monitor and a display method of the biological information monitor that can reduce the burden on the doctor when administering an anesthetic.

Brief Description of the Drawings

[0023] [Figure 1] Perspective view showing the external configuration of the biological information monitor according to the embodiment [Figure 2] Block diagram showing the configuration of the biological information monitor of the embodiment [Figure 3] Diagram showing an example of a list display of age-corrected MAC displayed on the display unit [Figure 4] Diagram showing an example of a screen when the list display of age-corrected MAC is stopped [Figure 5] Diagram showing the relationship between age and MAC described in Non-Patent Document 2

Mode for Carrying Out the Invention

[0024] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0025] FIG. 1 is a perspective view showing the external configuration of the biological information monitor 10 according to the present embodiment.

[0026] The biological information monitor 10 has a display unit 101 on its front. Additionally, a standby switch 11 and an alarm indicator 12 are provided on the front of the biological information monitor 10.

[0027] One side of the vital signs monitor 10 is provided with a group of connectors related to the measurement of vital signs. Specifically, it includes an ECG (Electrocardiogram) connector 13a, an NIBP (Non-Invasive Blood Pressure) connector 13b, and an SpO2 connector 13c. Below the group of connectors is an additional module connection section 14 to which an additional module for realizing optional vital signs measurement processing can be attached. For example, an exhaled gas sensor 116 (Figure 2) can be connected to this additional module connection section 14. Incidentally, the other side of the vital signs monitor 10 (not shown) is provided with a USB connector, a LAN connection connector, and a recorder.

[0028] Figure 2 is a block diagram showing the configuration of the vital signs monitor 10. The vital signs monitor 10 is connected via a connector section 110 to vital signs detection units such as an electrocardiogram electrode 111 for detecting an electrocardiogram, a blood pressure measurement cuff 112 for detecting blood pressure, a body temperature sensor 113 for detecting body temperature, an SpO2 sensor 114 for detecting SpO2, a cardiac output sensor 115 for detecting cardiac output, and an exhaled gas sensor 116. The connector section 110 functions as an interface between the vital signs detection units and the measurement processing unit 104. The connector section 110 includes the ECG connector 13a, NIBP connector 13b, and SpO2 connector 13c shown in Figure 1.

[0029] The measurement processing unit 104 executes a predetermined measurement process by running a program stored in the memory unit 105. Through this measurement process, the measurement processing unit 104 measures the patient's biological information from the biological information detection unit (electrocardiogram electrodes 111, blood pressure cuff 112, body temperature sensor 113, SpO2 sensor 114, cardiac output sensor 115, and exhaled gas sensor 116) connected to the connector unit 110. Since conventionally known methods can be applied to the measurement of various biological information from the above-mentioned biological information detection unit, a detailed explanation thereof is omitted here.

[0030] Furthermore, the measurement processing unit 104 is capable of storing previously measured biological information in the storage unit 105, and reading biological information stored in the storage unit 105. In addition, the biological information obtained by the measurement processing unit 104 is displayed on the display unit 101 in the form of measured values ​​or waveforms via the display control unit 102.

[0031] The display unit 101 is, for example, a liquid crystal display with a touch panel, and not only has a display function to display biometric information, but also functions as an input unit that accepts user input operations. Specifically, the display control unit 102 changes the display on the display unit 101 and the processing of the measurement processing unit 104 by the user's touch operation of the display unit 101. Various setting values ​​can be input by the user's touch operation of the display unit 101. In this embodiment, user operations such as various settings are accepted by touch operation of the display unit 101, but user operations may also be accepted using, for example, a keyboard, mouse, or dedicated buttons.

[0032] In addition to the above configuration, the biological information monitor 10 of this embodiment has an age-corrected MAC calculation unit 200.

[0033] Here, the memory unit 105 stores the reference MAC for each of the multiple anesthetics. The reference MAC is the concentration of each anesthetic corresponding to MAC = 1.0.

[0034] The age-corrected MAC calculation unit 200 reads the reference MAC for each of the multiple anesthetics from the memory unit 105, and calculates the age-corrected MAC for each of the multiple anesthetics by multiplying the reference MAC for each of the multiple anesthetics by a coefficient corresponding to age.

[0035] In other words, the memory unit 105 and the age-corrected MAC calculation unit 200 function as age-corrected MAC acquisition units that acquire an age-corrected MAC for each of the multiple anesthetics based on age.

[0036] The age-corrected MAC for each of the multiple anesthetics calculated by the age-corrected MAC calculation unit 200 is displayed in a list on the display unit 101 via the display control unit 102. Furthermore, the age-corrected MAC for each of the multiple anesthetics calculated by the age-corrected MAC calculation unit 200 is output to the measurement processing unit 104.

[0037] Figure 3 shows an example of a list display of age-adjusted MAC values ​​shown on the display unit 101. The display area 301 displays a list of age-adjusted MAC values ​​for each of several anesthetics. This allows physicians to easily determine the concentrations of multiple anesthetics to be administered to a patient by looking at this list, as it displays the concentrations of each anesthetic corresponding to an age-adjusted MAC of 1.0.

[0038] In this embodiment, in addition to a list of age-adjusted MACs for each of the multiple anesthetics, a list of the unadjusted MACs on which the age-adjusted MACs are based is also displayed. The list of unadjusted MACs is displayed in display area 302, which is located next to display area 301.

[0039] The MAC value before age correction displayed in display area 302 can be changed by the user. This change affects the calculation result of the age-corrected MAC calculation unit 200, and consequently, the age-corrected MAC value displayed in display area 301 also changes.

[0040] In this embodiment, the display of the age correction MAC list in the display area 301 can also be stopped based on the user's touch operation of the ON / OFF button 303, as shown in Figure 4.

[0041] Next, the calculation of age-adjusted MAC by the age-adjusted MAC calculation unit 200 will be explained in detail. The age-adjusted MAC calculation unit 200 calculates the age-adjusted MAC for each anesthetic drug, for example, using the following formula.

[0042]

number

number

number

[0043] K(age)N2O, K(age)PAGT, and K(age)SAGT represent the N2O concentration (%), primary anesthetic gas concentration (%), and secondary anesthetic gas concentration (%), respectively, corresponding to an age-adjusted MAC of 1.0.

[0044] KN2O, K(PAGT), and K(SAGT) represent the N2O concentration (%), primary anesthetic gas concentration (%), and secondary anesthetic gas concentration (%), respectively, corresponding to an age-unadjusted MAC=1.0.

[0045] f(age) is a correction factor according to age. In this embodiment, f(age) is, for example, expressed by the following formula.

[0046]

number

[0047] The age-corrected MAC (i.e., K(age)N2O, K(age)PAGT, K(age)SAGT) calculated by the age-corrected MAC calculation unit 200 using equations (2)-(4) are displayed in a list in the display area 301. Of course, the list displays the names of specific anesthetic drugs, not names such as primary anesthetic gas or secondary anesthetic gas.

[0048] The display example in Figure 3 shows a case where the patient's age is less than 40 years, and the age-adjusted MAC value for each anesthetic displayed in display area 301 is greater than the reference MAC value for each anesthetic displayed in display area 302.

[0049] Furthermore, the age-corrected MAC for each of the multiple anesthetics calculated by the age-corrected MAC calculation unit 200 is also output to the measurement processing unit 104. The measurement processing unit 104 calculates the age-corrected Total MAC (AGE) based on the concentration of the anesthetic in the exhaled gas using the following formula.

[0050]

number

[0051] As described above, according to this embodiment, an age-corrected MAC acquisition unit (storage unit 105, age-corrected MAC calculation unit 200) is provided to acquire an age-corrected MAC for each of the multiple anesthetic drugs, corrected based on age, and a display unit 101 is provided to display a list of the age-corrected MACs for each of the multiple anesthetic drugs acquired by the age-corrected MAC acquisition unit (storage unit 105, age-corrected MAC calculation unit 200). As a result, the concentrations of each anesthetic drug corrected according to the patient's age are displayed in a list, so that the physician can easily determine the concentrations of multiple anesthetic drugs to be administered to the patient by looking at this list. As a result, a vital signs monitor and a method for displaying vital signs monitors can be realized that can reduce the burden on physicians when administering anesthetic drugs.

[0052] The embodiments described above are merely examples of how the present invention can be implemented, and the technical scope of the present invention should not be limited by them. In other words, the present invention can be implemented in various ways without departing from its gist or its main features.

[0053] In the above-described embodiment, the case where the age-corrected MAC acquisition unit is composed of a storage unit 105 and an age-corrected MAC calculation unit 200 was mentioned. However, if the storage unit 105 stores in advance age-corrected MACs for each of the multiple anesthetics based on age, the age-corrected MAC calculation unit 200 may be omitted.

[0054] The above-described embodiment mentions a case where corrected MAC values ​​are obtained and displayed in a list for each of several anesthetics based on age. However, the present invention is not limited to this; essentially, it is sufficient to obtain and display corrected MAC values ​​for each of several anesthetics based on factors that affect the effectiveness of the anesthetic.

[0055] In other words, the biological information monitor of the present invention may be configured to include a corrected MAC acquisition unit that acquires a corrected MAC for each of a plurality of anesthetics based on factors that affect the effectiveness of the anesthetic, and a display unit that displays a list of the corrected MACs for each of the plurality of anesthetics acquired by the corrected MAC acquisition unit.

[0056] The display unit may also display a list of the original MACs on which the corrected MACs were derived, in addition to a list of the corrected MACs for each of the multiple anesthetics.

[0057] The value of the MAC before correction displayed on the display unit can be changed by the user, and the value of the corrected MAC displayed on the display unit may be changed in accordance with the change in the value of the MAC before correction.

[0058] The corrected MAC acquisition unit may include a storage unit that stores a reference MAC for each of the multiple anesthetics, and a corrected MAC calculation unit that calculates a corrected MAC for each of the multiple anesthetics by multiplying the reference MAC for each of the multiple anesthetics by a coefficient corresponding to the factor.

[0059] The aforementioned factors may include at least one of atmospheric pressure and body temperature. In other words, since the effectiveness of anesthetics changes depending on atmospheric pressure and patient body temperature, a corrected MAC (Anesthetic Gas Concentration) may be obtained and displayed in a list for each of several anesthetics based on atmospheric pressure and patient body temperature. For example, since the effectiveness of anesthetics decreases as atmospheric pressure decreases, a corrected MAC (anesthetic gas concentration) may be obtained and displayed in a list for each of several anesthetics, such that it increases as atmospheric pressure decreases. Alternatively, a corrected MAC that reflects a combination of multiple factors such as age, atmospheric pressure, and body temperature may be obtained and displayed in a list.

[0060] Furthermore, pregnant women may be added as a factor. Generally, MAC is considered to decrease in pregnant women, so for example, in the case of pregnant women, a corrected MAC (anesthetic gas concentration) that is higher for each of the multiple anesthetic drugs than for non-pregnant women may be obtained and displayed in a list. [Industrial applicability]

[0061] The present invention is widely applicable to biological information monitors capable of displaying MACs and methods for displaying biological information monitors. [Explanation of Symbols]

[0062] 10. Biometric Information Monitor 101 Display section 102 Display Control Unit 103 Alarm Indicator 104 Measurement Processing Unit 105 Storage section 110 Connector section 200 Age-corrected MAC calculation unit

Claims

1. A corrected MAC acquisition unit acquires multiple corrected MACs for each of several anesthetic drugs, corrected based on factors that affect the effectiveness of the anesthetic drug. The connection part to which the exhaled gas sensor is connected, A processing unit that calculates a total corrected MAC using the aforementioned multiple corrected MACs and the concentration of the anesthetic in the patient's exhaled gas obtained by the exhaled gas sensor, A display unit that displays a list of corrected MACs for each of the multiple anesthetics acquired by the corrected MAC acquisition unit, A biometric information monitor equipped with the following features.

2. The aforementioned display unit is In addition to a list of corrected MACs for each of the aforementioned multiple anesthetics, a list of the uncorrected MACs on which the corrected MACs were based is displayed. A biological information monitor according to claim 1.

3. The MAC value before correction displayed on the display unit can be changed by the user. The value of the corrected MAC displayed on the display unit is changed in accordance with the change in the value of the MAC before correction. The biological information monitor according to claim 2.

4. The aforementioned correction MAC acquisition unit, A memory unit that stores a reference MAC for each of the aforementioned multiple anesthetics, A corrected MAC calculation unit calculates a corrected MAC for each of the multiple anesthetics by multiplying the standard MAC for each of the multiple anesthetics by a coefficient corresponding to the factor, Equipped with, A biological information monitor according to any one of claims 1 to 3.

5. The aforementioned factors include the patient's age, A biological information monitor according to any one of claims 1 to 4.

6. The aforementioned factors include at least one of atmospheric pressure and body temperature. A biological information monitor according to any one of claims 1 to 5.

7. The processing unit calculates a value for each anesthetic by dividing the concentration of the anesthetic in the exhaled gas by the corrected MAC, and calculates the total corrected MAC by adding up these divided values. A biological information monitor according to any one of claims 1 to 6.

8. A corrected MAC acquisition step is to obtain multiple corrected MACs for each of several anesthetics, corrected based on factors that affect the effectiveness of the anesthetic, and The steps include inputting patient exhaled gas information from an exhaled gas sensor, A step of calculating a total corrected MAC using the aforementioned multiple corrected MACs and the concentration of the anesthetic contained in the patient's exhaled gas. A display step which displays a list of corrected MACs for each of the multiple anesthetics obtained in the corrected MAC acquisition step, A method for operating a vital signs monitor, including the operation of such a device.

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