JPH037137A - Continuous blood-pressure monitoring device - Google Patents

Abstract

PURPOSE:To shorten the measuring time, catch a quick change in blood pressure, prevent blood stagnation in a patient, and thereupon perform accurate measurement of his blood pressure by referencing the pulsed wave parameters to a pulsed wave parameter characteristics stored in memory, and deciding the blood pressure value through specified logical calculations. CONSTITUTION:A cough pressure signal from a pressure sensor 4 is amplified by an amplifier 6 and digital converted by an A/D converter 8, the result to be taken in by an MPU 10. Meantime the cough pressure signal is fed to a band-pass filter 7, and pulsed wave signals sensed thereby are digital converted by the A/D converter 8 and taken in by the MPU 10. The MPU 10 is equipped with a function to decide the blood pressure value from the amplitude of pulsation obtained in the course of extra-slow speed decompression in the cough 2, a function to calculate the pulsed wave parameters, a function to store the relation between the pulsed wave parameters and relative pressure in a memory 10a, a function to calculate the membership function on the basis of the pulsed wave parameters obtained through short-time measurement and the characteristics function, and a function to decide the blood pressure value from this membership function. A display 9 is connected with the MPU 10 to display the blood pressure value, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention relates to a continuous blood pressure monitoring device that continuously monitors a subject's blood pressure by indirect measurement.

(b) Conventional technology In general, when measuring blood pressure in critically ill patients or patients undergoing surgery, rapid measurement is required and it is also necessary to capture steep blood pressure fluctuations, so this method is called the direct method (H blood sedimentation). method is used. This method involves inserting an indwelling needle into the patient's artery and directly measuring the intraarterial pressure using a pressure sensor connected to it, which is constantly displayed. There are many clinically unfavorable points such as a high degree of invasiveness.

Therefore, in recent years, for example, a cuff is attached to the upper arm, and the air pressure inside the cuff (hereinafter sometimes referred to as cuff pressure) is reduced or increased at a constant rate, and during this process, Korotkoff sounds and pulse waves are generated. Continuous blood pressure monitoring devices have appeared that automatically and intermittently perform indirect measurements (referred to as the Rivaro and Fuchi methods) to determine blood pressure values using blood vessel information. This continuous blood pressure monitoring device requires only a cuff to be attached, so it is safer and the measurement procedure is simpler than the direct method.

(c) Problems to be Solved by the Invention In the indirect measurement continuous blood pressure monitoring device described above, it is necessary to change the cuff pressure at a predetermined rate over the range from systolic pressure or higher to diastolic pressure or lower. The time required for the same measurement ranges from several tens of seconds to more than one minute, making it impossible to quickly determine blood pressure 1jll+, and making it difficult to detect rapid blood pressure fluctuations.

In addition, in the above-mentioned continuous blood pressure monitoring device, since the arterial blood flow is temporarily stopped by the cuff, repeating measurements without a time interval may cause blood stasis and make accurate III determination impossible, especially for patients with blood circulation disorders. is clinically unfavorable.

Furthermore, in devices that measure blood pressure during the cuff decompression process, the cuff must be pressurized above the systolic pressure before decompression begins, but if this pressurization is insufficient, the blood pressure value cannot be determined, so measurements must be taken again. There are issues that need to be addressed. For these reasons, direct measurement is still the mainstream for continuous blood pressure monitoring.

This invention has been overlooked above, and is intended to significantly shorten measurement time, detect rapid blood pressure fluctuations, prevent blood stasis in patients, perform accurate blood pressure measurements, and prevent blood pressure from being insufficiently pressurized. The purpose is to provide a continuous blood pressure monitoring device that makes it possible to avoid re-measurement.

(d) Means for Solving the Problems In order to solve the above problems, the continuous blood pressure monitoring device of the present invention has the configurations listed in the following items i-ix.

i: a cuff attached to the subject; ii: pressure adjustment means for adjusting the air pressure within the cuff; iii: pressure detection means for detecting the air pressure within the cuff; iv: detecting cardiovascular information from the subject. (2) Cardiovascular information detected by the cardiovascular information detection means and the inside of the cuff detected by the pressure detection means in the process of changing the air pressure inside the cuff by the pressure adjustment means; vi: a pulse wave detection means for detecting a pulse wave from a subject, and ■ i
: A pulse wave parameter calculating means for calculating a plurality of parameters representing the pulse wave waveform from the pulse wave detected by the pulse wave detecting means; viii: In the process of determining the blood pressure value by the blood pressure value determining means,
Pulse wave parameter characteristic storage means for storing the relationship between the pulse wave parameter obtained by the pulse wave parameter calculation means for the pulse wave detected by the pulse wave detection means and the blood pressure value determined by the blood pressure value determination means. and iX: After the air pressure in the cuff is increased to a predetermined pressure by the pressure adjustment means, the pulse wave parameter is determined by the pulse wave parameter calculation means for one or several pulse waves detected by the pulse wave detection means. and a second blood pressure value determining means that calculates the pulse wave parameters, compares each pulse wave parameter with the pulse wave parameter characteristics stored in the pulse wave parameter characteristics storage means, and determines the blood pressure value by a predetermined logical operation. It is characterized by:

(e) The waveform of the action pulse wave changes with cuff pressure, and the change has a predetermined relationship with the blood pressure value. This relationship is approximately constant for human T1 patients if the patient is stable.

Therefore, by setting this relationship to 1 and setting it to V, it is possible to determine the blood pressure value simply by detecting the pulse wave and evaluating the waveform.

In the blood pressure monitoring device according to the present invention, the waveform of the pulse wave is determined by, for example, pulse wave range width, pulse wave integral level, waveform width ratio, ti'iq
+lf+ +) 7th grade? We are trying to evaluate using Wek parameters. Then, as in the past, the blood pressure value is determined with the cuff's reduced pressure over culm or; It is stored in association with the blood pressure value.

If the relationship between the pulse wave parameter and 1f1 [positive value is memorized, the brain can detect at least one pulse wave and the cuff pressure at that time, and calculate the pulse wave parameter for this pulse wave. The blood pressure value can be determined by applying a predetermined logic meter 17 to the above relationship.

In this way, since the continuous surface pressure monitoring device of the present invention only needs to detect one pulse wave in principle, the measurement time can be significantly shortened and sudden changes in blood pressure can be detected. At the same time, it is possible to prevent the patient from congesting blood and perform accurate blood pressure measurement. Further, although it is necessary to pressurize the cuff when detecting a pulse wave, the pressure at that time only needs to be able to detect a pulse wave, and there is no need to set it strictly, so there is almost no possibility that measurement will not be possible due to insufficient pressurization.

(f) Example An embodiment of the present invention will be described below based on the drawings.

FIG. 8 is a block diagram illustrating the configuration of the continuous blood pressure monitoring device of this embodiment. A cuff 2 is attached to the upper arm of the subject, and an exhaust valve 3, a pressure pump (pressure adjustment means) 4, and a pressure sensor (pressure detection means) 5 are connected to the cuff 2. The exhaust valve 3 and the pressurizing pump 4 are MPUl0
controlled by The output signal of the pressure sensor 4 (hereinafter referred to as cuff pressure signal) is amplified by an amplifier 6, and one signal is directly input to an analog/digital (A/D) converter 8 for digital conversion, and then taken into the MPU10. It will be done. On the other hand, the cuff pressure signal is input to a bandpass filter and a pulse wave signal is detected. This pulse wave signal is also digitally converted by the A/D converter 8 and taken into the MPU10.

MPU10 has the function of determining the blood pressure value from the amplitude of the pulse wave obtained by the slow σ pressure overculm of cuff 2 (normal measurement), the function of calculating the pulse wave parameter, and the function of calculating the pulse wave parameter relative to the pulse wave parameter obtained by normal measurement. The relationship between the blood pressure (difference between the cuff pressure and the blood pressure value determined by Jmm measurement) (hereinafter referred to as a characteristic function) is stored in the memory 10a, and the pulse rate obtained by the short-time measurement described later is used. It has a function of outputting 17 membership functions based on wave parameters, meters and characteristic functions, and a function of determining blood pressure values from these membership functions.

A display 9 is connected to the MPU10, and the determined 1 (...pressure, etc.) is displayed.Although not shown, a printer may be connected to print out the blood pressure value. good.

Next, the overall operation of the continuous blood pressure monitoring device according to the embodiment will be explained below with reference to FIG.

First, normal measurement is performed [step (hereinafter referred to as ST) 1]. In this normal measurement, after the cuff 2 is rapidly inflated to a predetermined initial pressure, it is based on the amplitude of the pulse wave (this amplitude also serves as one of the pulse wave parameters) obtained during the slow air flow process of the cuff 2. During this time, pulse wave parameters are also calculated and the pulse wave parameters and relative pressure are stored in the memory 10a.

In Sr1, it is determined whether a predetermined time (measurement interval) has elapsed after the end of normal measurement. If this judgment is No, it waits at this Sr1, and if it is YES, it waits at Sr1.
Branch to 1.

In Sr1, short-time measurements are performed. In this short-time measurement, after pressurizing the cuff 2 to a predetermined pressure, several pulse waves are detected to determine the blood pressure value.

In Sr1, if the blood pressure value that appears in the short-time measurement of Sr1 has a large fluctuation compared to the blood pressure value of the previous measurement, or if it exceeds or falls below a preset warning value, Sr1
Branch to r1, otherwise branch to Sr1. In Sr1, an emergency measurement is performed, but this measurement is the same as the normal measurement. The initial pressure at this time is set to a value as low as possible within a measurable range based on the systolic pressure obtained in the previous short-time measurement so that the blood pressure value can be obtained more quickly.

In Sr1, it is determined whether or not the measurement has ended. This judgment is Y
In the case of ES, the measurement ends, and in the case of NO, the process branches to Sr1. In Sr1, it is determined whether short-time measurements have been performed a predetermined number of times, and if the determination is YES, the process branches to STI, and if the determination is No, the process branches to Sr1. That is, normal measurements are performed every predetermined number of times and the characteristic function is recalculated.

Next, the details of the above normal measurement are shown in Figures 6, 7 and 1.
This will be explained with reference to FIG.

First, an overview of blood pressure determination in this normal measurement process will be explained with reference to FIG. The pulse wave amplitude AMP gradually increases with slow evacuation of the cuff until it reaches the maximum value AM! After taking X, it will decrease again. On the increasing side of pulse wave amplitude, A II
Cuff pressure P corresponding to 50% amplitude of AM.

is determined as the systolic pressure SYS, and A□8 on the decreasing side of the pulse wave amplitude.
The cuff pressure PC corresponding to an amplitude of 70% of the diastolic pressure DIA
I decide. Of course, the method of normal measurement is not limited to this. Note that the blood pressure value may be determined using Korotkoff sounds, but even in this case, it is necessary to detect the pulse wave and calculate and store the pulse wave parameters. The specific processing will be explained below.

First, MPU10 closes the exhaust valve 3 and starts operating the pressurizing pump 4 (ST201, see FIG. 11).

The MPU 10 takes in the cuff pressure signal from the A/D converter 8 (ST202), and determines whether the cuff pressure has reached a predetermined initial pressure (ST203). If this determination is No, the process branches to Sr102, and if this determination is YES, the process branches to Sr104.

This initial pressure needs to be a value slightly higher than the patient's systolic pressure, and needs to be set in advance.

At 5T204, MPU10 stops the pressurizing pump 4 and puts the exhaust valve 3 into the slow exhaust state (ST205). Then, the counter n and the maximum pulse wave amplitude value A
Both Xs are set to zero (ST206).

Sr10? Then, MPU10 takes in the cuff signal and further takes in the pulse wave signal (ST20B).

The MPU10 applies the threshold value TH, to the pulse wave signal P-, and divides the pulse wave signal P,4 into beats (S7209,
(See Figure 6). Then, MPU10 determines whether or not break point T7 has been detected, and if No, branches to Sr107 and continues detection of cuff pressure and pulse wave.

If the determination at 5T210 is YES, the process branches to Sr111 and n is incremented by 1. Then, in 5T212, the pulse wave parameter (wavelength 1
111i1AMP, integral level RAV.

Waveform width ratio WID and curvature ratio C0N) and average cuff pressure P
C(n) and store it in the memory loa. Note that the pulse wave parameter calculation process will be described later.

In Sr113, MPU10 determines whether the amplitude AMP(n) of the n-th pulse wave is equal to or greater than A□8. If this determination is NO, the process branches to Sr115, and if this determination is YES, the process branches to Sr114. In 5T214, this AMP(n) is set as a new A IRI K. And in 5T215, AMP(n) is A. , l is less than 70%.

If this determination is NO, the process branches to Sr107 and the next pulse wave is detected. On the other hand, if this determination is YES, the process branches to 5T216 and proceeds to determine the blood pressure value.

In Sr116, MPUl0 has a determination of 5T215 as Y.
The cuff pressure PC(n) corresponding to the pulse wave at the time of ES is determined as the diastolic pressure DIA. In the next step 5T217, n at this time is placed in the counter m. Continuation < In Sr118, this m is decremented by 1, and A M P (m) becomes A m
It is determined whether a is smaller than 50% of x. If this determination is No, the process branches to 5T21B and continues searching for AMP(n).

If the determination at Sr119 is YES, the process branches to Sr120, and the cuff pressure PC(m) corresponding to m is set as the systolic pressure SYS. At 5T221, the MPU 10 puts the exhaust valve 3 into the rapid exhaust state to release the patient's upper arm from compression. Furthermore, in Sr122, MPolo displays SYS and DIA on the display 9, and the processing after S'F223 is based on the relative pressure P.
C.S., P. This is the V output. First, set the counter k to 1 (Sr12 J ), increment this k by 1 (ST224), and calculate the relative pressure P to the systolic pressure SYS.
Calculate with (+) 2 below cs(k) heather (ST225)
.

pcs(k) = P((b) −5ys ・
(1) Also, the relative pressure P co(
k) is calculated using the following equation (2) (ST226).

Pco(k) −P, (k) −D I A
-=(2) S i' In 227, it is determined whether k has become equal to n, and if this determination is No, S
The process branches to r124 to continue the process, and in the case of YF, S, the jll measurement is completed and the process returns to the main routine of FIG. Of course, the obtained pcs and PCD are set to 1 and 3 to the memory IOa.

Next, the short-time measurement process will be explained, but before that, the pulse wave parameter calculation process will be explained with reference to FIGS. 5 and 10.
I will explain.

In the continuous blood pressure monitoring device of this embodiment, the pulse wave parameters include pulse wave amplitude AMP, integral level RA■, and waveform width ratio WI.
D, 4TIl type with flexural index CON is adopted. Of course 1. The ff1M wave parameters are not limited to these four.

First, MPUl0 searches for the time T II @ , pulse wave minimum value PWmi, , is written in the memory lOa (see (a) in FIG. 5 of S'T"101). Then, from PWMaX, P"min
The pulse wave amplitude A M P is calculated by subtracting (ST102
).

Next, the integral level RAV (%), which is the value obtained by normalizing the time average of the pulse wave Pw(t) by the amplitude AMP, is calculated using the following (3).
Calculated using the formula (STI03, see (b) in Figure 5)
.

Next, the waveform width ratio WID (%) is calculated (ST104 to 5T108, see 5th (C)), and this WI[) is calculated based on the maximum value PWmax of the pulse wave Pw(t). It is a value obtained by normalizing the time required for the pulse wave to decrease to a predetermined threshold value TH by the frequency up<'r, , -T, of the pulse wave.

The threshold value TH is set using the above equation (4), but
X in this formula (4) is a constant predetermined in the range of 0 to [(Sr1.04).

'r'tl+=Pw,,ll,l-+-AMPXx
-<4) Next, time (T.X is 5T105),
Add the Zumbling width Δ to this (STI06), and determine whether the pulse wave Pw(t) for this (is less than or equal to TH) (ST107). If 5TI07 il+ is constant or NO, branch to 5T106. If YE'', 3, branch to 5T108. In 5T10B, the next (5
)2 to calculate WID.

Here, Td,c is the time when P disease (1)≦T [(,).

Finally, calculate the curvature CON (%) (ST109~
5TIII). This CON is a point T that internally divides the time interval (T, , , T, , ) between the maximum point and the minimum point within it by a certain predetermined ratio y. 0, it is the relative ratio between the reference straight line connecting the maximum and minimum points of the pulse wave and the pulse wave Pw(t).

First, find T c a n using (6) 2 below (
ST109). Here, y is a constant preset in the range of 0 to j.

Tcan=T*ax+ (Tan Tmax) X>
' - (6) Next, the level Ref of the reference plane and line at T c tt n is calculated by the following (7) 2 (STIIO).

Ref=Pw aax −AMPXy ---(7
) Then, CON is calculated using the following equation (8).

Next, short-time measurement will be explained. First, the pressurization set value is determined by the average value of systolic pressure and diastolic pressure ((SYS+DIA) /
2) (ST301, see FIG. 12). Note that the pressurization setting for short-term measurement only needs to be between the systolic pressure and the diastolic pressure, and does not need to be set strictly.

Next, pressurize the cuff 2 to this pressurization setting value (ST30
2). The following processing from 5T303 to Sr109 is as follows:
The cuff pressure PC may be maintained at this pressure setting value, or
It may also be carried out in a slow evacuation state.

In Sr103, set the counter i to zero, and next 5T30
4, this i is incremented by 1.

Furthermore, in Sr105, the pulse wave is divided into each beat as in the previous Sr109, and the pulse wave r:U, I-1-9A, RAV, WI DS C0N is calculated for the divided pulse waves and is stored in the memory 10a. do. Also, the cuff pressure PC at that time
is also stored in the memory 10a (ST307).

In Sr10B, it is determined whether or not i has reached a predetermined number. This predetermined number is set so that several pulse waves can be detected. In short-time measurements, in principle it is only necessary to detect the pulse wave for one beat, but in reality, due to body movements etc.
Since accurate pulse wave parameters may not be obtained in some cases, in this embodiment, several pulse waves are detected, pulse wave parameters are calculated for each pulse wave, and the arithmetic mean value of these is taken.

For Sr109, the average value of pulse wave parameters V□13, V
raw % Vwid, Vco, . . . and the average cuff pressure 41 p are calculated, stored in the memory 10a, and the exhaust valve 3 is put into a rapid exhaust state to release the upper arm from compression (ST310).

In Sr111, membership functions are calculated by applying data to pulse wave parameters, and in Sr112, logical calculations are performed on these membership functions to determine blood pressure values SYS and DrA.

Details of the processing of Sr111 and 5T312 will be described later.

The finally determined blood pressure values SYS and DrA are displayed on the display 9 (ST313), and the short-time measurement is ended.

Next, the membership function calculation process of Sr111 and the logical calculation process of Sr112 will be explained. In the following explanation, only the case of systolic pressure will be explained, but the same applies to the case of diastolic pressure.

First, an overview of membership function calculation will be explained with reference to FIG. FIG. 3(a) shows an example of the amplitude AMP characteristic function obtained by normal measurement. In the subsequent short-time measurement, if the amplitude of the pulse wave captured by the cuff pressure PC was V 11191, then this cuff pressure PC is
P C3I + higher than systolic pressure SYS or P C91
It is likely to be around 2 or lower.

This will be expressed by a membership function as shown in FIG. 3(b). In this figure, the horizontal axis is the relative cuff pressure P
. , and the vertical axis is the probability that the relative cuff pressure PC3 at the time of capturing the pulse wave is that value. In this embodiment, the shape of the membership function curve is a triangle whose apex (maximum point) is a point (intersection) equal to V and □ of the pulse wave characteristic function and whose base has a certain predetermined width.

There may be multiple points of intersection, and there are as many triangles as there are points of intersection. For example, in the case of (b) in Figure 3, the intersection is 2
Therefore, there are also two triangles.

Further, these triangles may partially overlap as shown in FIG. 3 (C), and in this embodiment, the maximum value of these triangles is taken as one membership function. Furthermore, since the data stored in the memory 10a is Mh-like, in this embodiment linear interpolation calculations are performed to calculate membership functions with higher accuracy.

In the above explanation, the pulse wave amplitude was taken as an example, but the same applies to other parameters. The value of the maximum point of the membership function and the width of the base of the triangle can be set by considering the weighting and reproducibility of each pulse wave parameter, but in this example, they are unified for each pulse wave parameter. .

Next, specific processing will be explained. First, the pointer X is set to the minimum value P C3ffir+ of the relative cuff pressure PC9, and the counter j is set to 1. (ST401).

The pointer If so, branch to ST402 and proceed to Y
In the case of ES, the process branches to S 1'' 404.

In Sr404, as shown in FIG. 4, G, XC (J) are linearly interpolated using the following equation (9).

Xc(j)=Pes(x-1) (Pcs(x-1)
PC9(X)I×A...(9) AMP(X-1)-Va,.

Furthermore, from this XC(j), the membership function φ4□
(P, 5, Xc(N) is calculated using the following formula 00).

φaMp(Pcs, Xc(j)) (Xc(j)<Pcs≦Xc(j) + 10 mm1
g1O(Pcs>Xc(j)+10mmff) ・-
00)t Suh Chi, base 20 centered on Xc(j)
+nml! It becomes an isosceles triangle of g.

For Sr406, increment j by 1 and get 5T407
Then, it is determined whether or not X has reached the maximum value P csmax of the relative cuff pressure. If this judgment is NO, Sr40
Branches to 2, and if YES, branches to 5T408.

There are two or more intersection points and multiple membership functions φ
ml'IP (P C9, Xc (1)), -...
φamp(P=s, Xc(j)) may exist, so the membership function Φ that takes the maximum value among them,
02 (Pcs) is calculated (Sr408).

Φ,, p(Pcs) = MAX (φash(Pcs, X c(1) ),
−・・φxmp(Pcs, X c (j) ) Sr40
In 9.5T410.5TIII, o---<pcs>
Similarly, for the integral level waveform width ratio and curvature, respectively, the mempage knob function, Φ1 (Pcs), Φ
−+a (Pcs), Φ,. , (PC3) is calculated. Now, for example, the characteristic functions of amplitude AMP, integral level RAV, waveform width ratio WID, and curvature index COH are as shown in (a), (b), (C), and (dlO) in Figure 2, respectively, and the utilization of short-time measurement is V harp , Vrxv , Vw+d, V
co.

, then the mempage-knob function Φ, , (PcS
), Φ,, v (PcS), 0-1d (Pcs)
,Φ,. , l (P, ,) are (a) in Figure 1, respectively.
(b) (C) (It becomes like (1).

Next, logical calculation processing will be explained. The outline of this logical calculation is the membership function Φa, np (Pcs),
Φr,v(Pcs), O,i-(Pcs), Φ-
Φ(Pcs) which is the minimum straightness of 0,,(pcs) is 17
The maximum value of this Φ(Pcs) is 1 vs. the cuff pressure P.
cs is determined, and the systolic pressure SYS is obtained (see Figure 1).

First, pointer X is the minimum value of relative Cuff river P C5m1n
Along with that, ΦMIX's first! IJI (Set if to O (Sr501, see Figure 14). Next, increment X by 1 to 5T502), and use the mempage knob function Φ
(x) is calculated using the following formula 02) (Sr103).

Φ(x) - Old N [Φmap (X), Φrav (
X), Φwld (x), Φ,. ,,(X))...
・02) In S T 504, this Φ(x) is Φ. 1. Determine whether it is greater than 1. If this judgment is NO, 5T50
Branch to 6, ¥ E', Sr10 in case of S (7)
Branch to 5. For Sr105, X at this time is X. 1X
Let Φ(χ) be Φm□. In Sr106,
X is the maximum value P of relative cuff pressure. , □, is determined, and if this determination is No, the process branches to Sr102,
If YES, the process branches to Sr107. Sr107 calculates the systolic pressure SYS based on the following equation 03).

5ys-ding (+ XIIIX...03
) Here, D is the cuff pressure detected during the short-term measurement.

(g) As described in detail of the invention, the continuous blood pressure monitoring device of the present invention includes a pulse wave detection means for detecting a pulse wave from a subject, and a pulse wave detected by the pulse wave detection means. a pulse wave parameter calculating means for calculating a plurality of parameters representing a waveform; and a blood pressure value determining means that calculates a plurality of parameters representing a waveform. The relationship between the pulse wave variation and the blood pressure value determined by the blood pressure value determining means is described below. After the air pressure in the cuff is adjusted to a predetermined pressure by the pulse wave parameter characteristic recording means and the pressure adjusting means, the pulse wave is determined for one or several pulse waves detected by the pulse wave detecting means. a second method that calculates pulse wave parameters by the parameter calculation means, compares each pulse wave parameter with the pulse wave parameter characteristics stored in the pulse wave parameter characteristic storage means, and determines the blood pressure value by a predetermined logical operation; and blood pressure value determining means.

Therefore, it has the advantage of greatly shortening measurement time, capturing rapid blood pressure fluctuations, preventing patient's congestion, and being able to accurately measure blood pressure, making measurements impossible due to insufficient pressure. It rarely happens. Therefore, the advantages of indirect measurement, which are easy to operate and have excellent safety, can be fully utilized.

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating an example of the membership function of the continuous blood pressure monitoring device of the present invention, and FIG. 2 is a diagram illustrating an example of the characteristic function 01 of the pulse wave parameter of the continuous blood pressure monitoring device.
Figure 3 is a diagram illustrating the process of calculating the membership function from the pulse wave amplitude characteristic function of the continuous blood pressure monitoring device, and Figure 4 is the interpolation calculation when calculating the membership function of the continuous blood pressure monitoring device. FIG. 5 is a waveform diagram illustrating calculation of pulse wave parameters in the continuous blood pressure monitoring device, FIG. 6 is a waveform diagram illustrating pulse wave separation processing in the continuous blood pressure monitoring device, and FIG. 8 is a block diagram illustrating the configuration of the continuous blood pressure monitoring device, and FIG. 9 is a diagram illustrating blood pressure value determination in normal measurement processing of the continuous blood pressure monitoring device. FIG. 10 is a flowchart explaining the overall operation of the continuous blood pressure monitoring device. FIG. 11 is a flowchart explaining normal measurement of the continuous blood pressure monitoring device. FIG. 12 is a flowchart explaining the short-time measurement process of the continuous blood pressure monitoring device, FIG. 13 is a flowchart explaining the membership function calculation process of the continuous blood pressure monitoring device, and FIG. 14 is a flowchart explaining the membership function calculation process of the continuous blood pressure monitoring device. FIG. 3 is a flow diagram illustrating logical calculation processing of the monitoring device. 2: Cuff, 3: Exhaust valve, 4: Pressure pump, 5: Pressure sensor, 7: Band pass filter, 10: MPU. Figure 1

Claims (1)

[Claims] (1) A cuff worn by a subject; a pressure adjustment means for adjusting air pressure within the cuff; a pressure detection means for detecting the air pressure within the cuff; and cardiovascular information detection for detecting cardiovascular information from the subject. and in the process of changing the air pressure in the cuff with the pressure adjustment means, the blood pressure is determined based on the cardiovascular information detected by the cardiovascular information detection means and the air pressure in the cuff detected by the pressure detection means. A continuous blood pressure monitoring device comprising a blood pressure value determining means for determining a blood pressure value, a pulse wave detecting means for detecting a pulse wave from a subject, and a pulse wave waveform detected by the pulse wave detecting means. pulse wave parameter calculation means for calculating a plurality of parameters representing the pulse wave parameter calculation means; pulse wave parameter characteristic storage means for storing the relationship between wave parameters and the blood pressure value determined by the blood pressure value determination means; and after the air pressure in the cuff is increased to a predetermined pressure by the pressure adjustment means, the pulse wave For one or several pulse waves detected by the detection means, the pulse wave parameter calculation means calculates a pulse wave parameter, and each pulse wave parameter is converted into a pulse wave parameter stored in the pulse wave parameter characteristic storage means. 1. A continuous blood pressure monitoring device comprising: second blood pressure value determination means that determines the blood pressure value by comparing the characteristics with the blood pressure value and performing a predetermined logical operation.