JPH062125B2 - Automatic blood pressure monitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Industrial field of application) The present invention is a digital system that automatically measures systolic pressure (highest blood pressure) and diastolic pressure (lowest blood pressure) using a cuff. The present invention relates to an automatic sphygmomanometer capable of displaying a pseudo blood pressure waveform at the same time as displaying.

(Prior Art) A conventional automatic sphygmomanometer automatically controls the pressure of a cuff wrapped around the upper arm of a subject to measure systolic pressure, diastolic pressure, and in some cases, average blood pressure and displays the measured value on the display unit. Can be displayed by numbers.

FIG. 7 shows a block diagram of a conventionally known automatic blood pressure monitor.

In this figure, the pressure of the cuff 1 wrapped around the subject is controlled by the cuff pressure controller 2, and the output signal of the pressure sensor 3 for detecting the cuff pressure is sent to the cuff pressure detector 4 and the pulse wave detector 5. .

The cuff pressure detection unit 4 sequentially detects the cuff pressure that is increased above the systolic pressure and then reduced, and sends a detection signal to the blood pressure value calculation unit 6. The pulse wave detector 5 detects the pulse wave in the process of reducing the cuff pressure and sends a detection signal to the calculator 6.

In the blood pressure value calculation unit 6, the pressure at the time when the magnitude of the pulse wave reaches a certain ratio of the maximum pulse wave during the depressurization process of the cuff pressure is determined as the systolic pressure, and the pulse wave after the maximum pulse wave is exceeded. The pressure at the time when the magnitude drops to a fixed rate of the maximum pulse wave is obtained as the diastolic pressure.

The systolic pressure and the diastolic pressure obtained by the blood pressure value calculation unit 6 are digitally displayed on the display unit 7.

(Problems to be Solved by the Invention) By the way, in the invasive blood pressure measuring method used in an operating room or the like, not only the blood pressure value of the subject can be displayed by a numeral but also the waveform of the pressure pulse wave can be simultaneously displayed. In this way, the condition of the subject can be intuitively and analogically monitored and monitored.

However, in the conventional automatic sphygmomanometer that non-invasively measures the blood pressure value using the cuff 1 shown in FIG. 7, since the blood pressure value is only displayed as numbers, the condition of the subject in the operating room is This sphygmomanometer is not enough for intuitive and analog understanding.

There are also sphygmomanometers that can display continuous pressure pulse waves in a non-invasive manner, but the cuff attached to a finger or arm is inflated for a long time to stop blood flow or squeeze the nerve with a sensor to invade the subject. Is a big problem.

The present invention has been proposed in order to solve such a problem, and can measure the blood pressure value noninvasively without invading the subject, and can also display the pseudo blood pressure waveform at the same time. The purpose is to provide an automatic blood pressure monitor.

[Structure of Invention]

(Means for Solving the Problems) In order to achieve the above object, the automatic blood pressure monitor according to the present invention is
A cuff wrapped around a part of the subject's body, a cuff pressure control unit that automatically controls pressurization and depressurization of the cuff, and a cuff that detects the cuff pressure from the sensor output from a pressure sensor connected to the cuff. A pressure detection unit, a pulse wave detection unit that detects a pulse wave from the sensor output from the pressure sensor, a cuff pressure signal from the cuff pressure detection unit and a pulse wave signal from the pulse wave detection unit from the systolic pressure. A blood pressure value calculation unit for calculating a value and a diastolic pressure value,
A pulse wave waveform extracting unit for extracting a pulse wave waveform from the pulse wave signal from the pulse wave detecting unit or a pulse wave signal obtained by another pulse wave detecting unit, and a systolic / diastolic pressure from the blood pressure value calculating unit. A display processing unit that creates a pseudo blood pressure waveform from the pulse wave signal from the pulse wave waveform extraction unit and the systolic pressure value and the diastolic pressure value calculated by the blood pressure value calculation unit are displayed numerically. In addition, the display unit is also provided for simultaneously displaying the pseudo blood pressure waveform created by the display processing unit.

(Operation) According to the configuration described above, the systolic pressure value and the diastolic pressure value are calculated in the blood pressure value calculation unit that finally processes the signal from the pressure sensor of the cuff wrapped around the upper arm of the subject. At the same time, the display processing unit performs a process of converting the maximum and minimum values of the pulse wave waveform into systolic / diastolic pressure values to create a pseudo blood pressure waveform.

Therefore, the display unit can digitally display the systolic / diastolic pressure value and simultaneously display the pseudo blood pressure waveform.

(Example) Hereinafter, the Example of this invention is described in detail based on drawing.

The block diagram of FIG. 1 shows an embodiment of the automatic blood pressure monitor according to the present invention. 2 is an operation waveform diagram of this automatic blood pressure monitor, and FIG. 3 is an operation flow chart of this automatic blood pressure monitor. In the description, the same parts as those in the conventional example will be denoted by the same reference numerals.

In these figures, the pressure in the cuff 1 wrapped around the upper arm of the subject is automatically controlled by the cuff pressure control unit 2 including a pressurizing pump, a pressure regulating valve and a control circuit. . A measurement interval signal is input to the cuff pressure control unit 2 from the input terminal 8 to determine how many minutes the blood pressure value is measured (step S1). Normally, this interval is set to a cycle of about 5 to 10 minutes.

The pressure of the cuff 1 is first increased by the cuff pressure control unit 2 to a pressure equal to or higher than the systolic pressure at time t1 in FIG. 2, and then gradually reduced over a period of Ta (steps S2 to S4).

The cuff pressure in the depressurization period Ta is detected by the pressure sensor 3 connected by the air conduit 9, and the detection signal is sent to the cuff pressure detection unit 3 and the pulse wave detection unit 5. The cuff pressure detection unit 4 sequentially detects the cuff pressure value that is being reduced. The pulse wave detector 5 detects the cuff pulse wave Pw1 shown in FIG. 2 (b).

The blood pressure value calculation unit 6, to which the detection signals from the cuff pressure detection unit 4 and the pulse wave detection unit 5 are supplied, holds this value at the time point t3 when the maximum value of the cuff pulse wave is detected, and at the same time, the maximum value of the cuff pulse wave. After 60 seconds, the diastolic pressure is detected at a time point t4 of 60% of the maximum pulse wave value, and this value (diastolic blood pressure value) is held. For the calculation of the systolic pressure, the cuff pressure at the time t2 of 50% of the pulse wave maximum value before the cuff pulse wave reaches the maximum value is read out from the memory in the calculation unit 6 and used as the systolic blood pressure value (step S5-S7). T in Fig. 2 (a)
b corresponds to the blood pressure value calculation period in the calculation unit 6.

The maximum and minimum blood pressure value signals calculated by the blood pressure value calculation unit 6 are supplied to the display processing unit 10.

Then, in order to be able to detect the cuff pulse wave having a well-shaped waveform, the pressure in the cuff 1 is reduced by the cuff control unit 2 to, for example, about 20 mmHg or less, which is less than the diastolic pressure in the period Tc (steps S8 to S9). . The pulse wave waveform after decompression is extracted by the pulse wave waveform extraction unit 11 to which the detection output from the pulse wave detection unit 5 is supplied and the decompression timing signal q1 is supplied from the cuff control unit 2 (step S10). . In FIG. 2, Pw2 is an enlarged view of the cuff pulse wave extracted by the pulse wave extracting unit 11.

The display processing unit 10 includes a blood pressure value calculation unit 6 and a pulse wave waveform extraction unit 11
Maximum value of cuff pulse wave based on the output signal supplied from
Pw (max) and the minimum value Pw (min) are made to correspond to the systolic blood pressure value SYS and the diastolic blood pressure value DiAS obtained by the blood pressure measurement, and the calculation for generating the pseudo blood pressure waveform W (t) is performed ( (See FIG. 4). This arithmetic expression is as follows.

W (t) = DiAS + {(SYS−DiAS) / Pw (max) −Pw (min)} × {Pw (t) −Pw (min)} where {Pw (max) −Pw (min)} is Corresponds to amplitude A. The processing so far corresponds to steps S11 to S12.

The pseudo blood pressure waveform W created by the display processing unit 10 by this calculation
(t) is displayed on the screen 12A of the display unit 12 together with the systolic blood pressure value SYS and the diastolic blood pressure value DiSA as shown in FIG. 5 (steps S13 to S14). At this time, the systolic blood pressure value SYS and the diastolic blood pressure value DiSA are digitally displayed beside the blood pressure waveform W (t). In the figure, reference numeral 13 is the pulse value of the subject. The display section 12 is composed of a CRT or a liquid crystal display panel.

Blood pressure waveform W (t) and blood pressure displayed on display screen 12A
SYS and DiSA are measured at the next intervals and then rewritten with new data (steps S15, S).
2 to S14). The display switching timing at this time is based on the reset signal q2 from the cuff pressure control unit.

Next, the configuration of the automatic blood pressure monitor of another embodiment shown in FIG. 6 will be described.

In this embodiment, the pulse wave waveform is not obtained from the pulse wave signal from the cuff 1, but is detected by a pulse wave sensor 14 such as a photoelectric pulse wave sensor sandwiched between fingertips. The detection output of 14 is supplied to the pulse wave detection unit 15.

The pulse wave signal obtained by the pulse wave detection unit 15 is the pulse wave waveform extraction unit 16
Is supplied to and the pulse wave waveform is extracted. The output signal of the pulse wave waveform extracting unit 16 is supplied to the display processing unit 10 and the same processing as that of the above-described embodiment is performed.

〔The invention's effect〕

As described above, according to the automatic blood pressure monitor of the present invention,
The blood pressure value can be digitally displayed on the display screen,
Since the pseudo blood pressure waveform can be displayed at the same time, it is suitable when it is desired to intuitively and analogically grasp and monitor the state of the subject in an operating room or the like.

Moreover, since the measurement is performed noninvasively using the cuff, it does not invade the subject.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the automatic sphygmomanometer according to the present invention, FIG. 2 is an operation waveform diagram for explaining the operation of the automatic sphygmomanometer of FIG. 1, and FIG. An operation flow chart showing an operation procedure, FIG. 4 is a waveform chart showing a pulse wave extracted by the pulse wave waveform extracting unit, FIG. 5 is a chart showing blood pressure values and pseudo blood pressure waveforms displayed on the display screen, and FIG. FIG. 7 is a block diagram showing an automatic blood pressure monitor according to another embodiment, and FIG. 7 is a block diagram showing a conventional automatic blood pressure monitor. 1 ... Cuff 2 ... Cuff pressure control unit 3 ... Pressure sensor 4 ... Cuff pressure detection unit 5, 15 ... Pulse wave detection unit 6 ... Blood pressure value calculation unit 9 ... Air pipeline 10 ... Display processing unit 11, 16 ... Pulse wave waveform Extraction unit 12 ... Display unit 12A ... Display screen 13 ... Pulse value 14 ... Pulse wave sensor SYS ... Systolic blood pressure value (maximum blood pressure value) DiSA ... Diastolic blood pressure value (minimum blood pressure value) W (t) ... Simulated blood pressure waveform

Claims (1)

[Claims] 1. A cuff wrapped around a part of a subject's body, a cuff pressure control section for automatically controlling pressurization and depressurization of the cuff, and a cuff based on a sensor output from a pressure sensor connected to the cuff. Cuff pressure detection unit for detecting pressure, pulse wave detection unit for detecting a pulse wave from the sensor output from the pressure sensor, cuff pressure signal from the cuff pressure detection unit and pulse wave signal from the pulse wave detection unit And a blood pressure value calculation unit for calculating a systolic pressure and a diastolic pressure value from the pulse wave signal from the pulse wave signal from the pulse wave detection unit or another pulse wave detection unit Pulse wave waveform extraction unit, a display processing unit that creates a pseudo blood pressure waveform from the systolic / diastolic pressure value signal from the blood pressure value calculation unit and the pulse wave waveform signal from the pulse wave waveform extraction unit, and the blood pressure value Displays the systolic pressure value and the diastolic pressure value calculated by the calculation unit in numbers. In addition, the automatic blood pressure monitor is provided with a display unit that simultaneously displays the pseudo blood pressure waveform created by the display processing unit.