JPH0558334B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a continuous systolic blood pressure measuring device for continuously measuring systolic blood pressure values.

[Prior Art and its Problems] Conventionally, a non-invasive blood pressure measurement method is well known as a method of measuring blood pressure. This non-invasive blood pressure measurement method indirectly measures the internal pressure of blood vessels from outside the skin, and generally involves wrapping a cuff around the upper arm and applying pressure inside the cuff until blood flow stops. Pressure operation. After pressurization, the cuff pressure is gradually lowered and the point at which blood starts flowing again is detected to measure the systolic blood pressure value. This non-invasive blood pressure measurement method uses a cuff to compress blood vessels during blood pressure measurement, blocking and restricting blood flow. Therefore, repeated measurements can cause cyanosis due to blood circulation disturbance downstream of the measurement point (hands, fingers). This made it impossible to measure blood pressure continuously over a long period of time. On the other hand, regarding the measurement of blood pressure, in exercise physiology, ergonomics, industrial medicine, psychology, and other fields, systolic blood pressure values that change rapidly due to exercise load, various stimuli, or changes in psychological state are continuously measured. There is a desire to measure accurately. In response to the above request,
Conventionally, attempts have been made to continuously measure blood pressure by attaching a cuff to the earlobe or fingertip. However, the above-mentioned attempt to continuously measure blood pressure is difficult to measure because the blood vessels to be measured are peripheral blood vessels, and because the measurement site is at a different height from the heart, there are problems such as correction of hydrostatic pressure differences, which makes it impractical. However, the results were insufficient and did not lead to sufficient results.

[Technical problem of the present invention]

Therefore, the present invention is a device for continuously measuring systolic blood pressure over a long period of time, which has excellent operability.
An object of the present invention is to provide a continuous systolic blood pressure measuring device that operates accurately and reliably.

[Technical means of the present invention]

In order to achieve the above-mentioned object, the present invention specifically provides a device that is directly attached to the skin surface at a measurement site in order to detect the displacement of the skin surface due to intravascular pressure, and is provided with the following features: (transformation)
a displacement detector that converts the amount of displacement into a change in electrical resistance and outputs the amount of displacement as an electrical signal; and a gas pressure chamber is formed around the measurement area to apply pressure to the measurement area from above the displacement detector. a cuff member that is connected to the gas pressure chamber in the cuff member, and includes a cuff internal pressure detector that detects the pressure of the gas pressure chamber, and an output at the time of systolic blood pressure detected by the displacement detector. cuff internal pressure control means for adjusting and controlling the internal cuff pressure in the cuff member so that the internal pressure of the cuff becomes 0, and the displacement detector detects a protrusion displacement of the skin surface near the blood vessel due to blood flow during heart beats. The cuff internal pressure is controlled by the cuff internal pressure control means according to this output signal, and when the maximum displacement value (systolic blood pressure value) in the displacement detector becomes equal to the cuff internal pressure, the cuff internal pressure is adjusted to the maximum. This constitutes a continuous systolic blood pressure measurement device that measures high blood pressure values.

[Example of the present invention]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The continuous systolic blood pressure measuring device according to the present invention will be described in detail below based on specific embodiments shown in the drawings.

FIG. 1 is a block diagram showing a continuous systolic blood pressure measuring device according to an embodiment of the present invention.
FIG. 2 explains the measurement principle of the device, and is a graph showing the relationship between the output of the displacement detector and the internal pressure of the cuff. First, the measurement principle of the continuous systolic blood pressure measuring device according to the present invention will be explained based on FIG. The relationship between the output of the displacement detector and the cuff internal pressure p is as shown in FIG. That is, when the cuff internal pressure in the cuff member is 0, the output of the displacement detector at the time of diastolic blood pressure is 0, and as the blood pressure rises, a positive output is generated, and at the time of systolic blood pressure, the displacement detector generates the maximum output. When the cuff internal pressure is gradually increased and the systolic blood pressure and the cuff internal pressure become equal, the displacement detector generates a negative output at the diastolic blood pressure, but becomes 0 at the systolic blood pressure. Furthermore, the cuff internal pressure is increased, and P>
When it becomes p, the output becomes negative even at the time of systolic blood pressure. The above aspects are summarized as follows.

Systolic blood pressure P: Cuff internal pressure p Displacement detector output Diastolic blood pressure Systolic blood pressure P>p Abbreviation 0 + P=p − 0 P<p − − On the other hand, in this invention, the cuff internal pressure is operated to follow the systolic blood pressure. That is, in FIG. 2, the displacement detector detects and outputs the displacement of the skin surface for each pulse pulse. When the output of the displacement detector at the time of systolic blood pressure is positive, the cuff internal pressure is increased, and if the output of the displacement detector at that time is 0 or negative, the cuff internal pressure is decreased to reduce the systolic blood pressure. Follow. The cuff internal pressure at this time is output as the systolic blood pressure value.

Next, a specific example of the inventive device will be explained based on FIG. This inventive device first includes a displacement detector 1 for detecting displacement of the skin surface due to intravascular pressure. The displacement detector 1 is composed of a strain gauge that has the function of converting pressure changes (deformation) into changes in electrical resistance, and is made of a film-like member such as a pressure-sensitive film. The displacement detector 1 is mounted directly on the skin surface S at a blood pressure measurement site, for example, at a location where the arterial blood vessel V is close to the skin surface S (such as the upper arm region or the pulsating region of the wrist).

On the other hand, in this invention device, the cuff member 2 is
It is made of an elastic bag body having a gas pressure chamber 3, and is attached to the blood pressure measurement site to which the displacement detector 1 is attached in such a manner as to cover the displacement detector 1. There is a blood vessel V on the skin surface S at the blood pressure measurement site where the displacement detector 1 and the cuff member 2 are attached.
Displacement occurs due to blood flow, and this displacement is detected by the displacement detector 1, converted into an electrical signal, and output. The displacement detection signal of the displacement detector 1 is amplified in a displacement amplifier 4, and output polarity discriminator 5
Enter. The output polarity discriminator 5 discriminates whether the displacement output signal is positive or negative and outputs it to the cuff internal pressure control circuit 6. The output polarity discriminator 5 outputs a pressurization signal to the cuff pressure control circuit 6 when the displacement detection signal shown in FIG. 2B has a positive output even at the time of systolic blood pressure, When the displacement detection signal is 0 or negative, a pressure reduction signal is output. The internal pressure of the cuff member 2 follows the systolic blood pressure P by the output of the cuff internal pressure control circuit 6 at each pulse interval shown in FIG. 2C. A cuff internal pressure detector 7 is connected to the cuff member 2 via a flow path 11, and the cuff internal pressure detector 7 constantly detects the internal pressure value of the cuff member 2 and outputs it as a systolic blood pressure value. Output to side 10. In this inventive device, the cuff internal pressure control circuit 6 is combined with a cuff internal pressure generator 8 constituted by means such as a pressurized air pump. Furthermore, for the purpose of output value correction, it is possible to omit the means at the time of measurement preparation and start, and to combine the displacement detector with the initial level automatic correction holder 9 as a correction means to facilitate handling. good.

[Effects of the present invention]

The continuous systolic blood pressure measuring device of the present invention configured as described above uses a strain gauge to detect the downward displacement of the skin surface near blood vessels due to blood flow during heart beats, and uses this output signal to increase the internal pressure of the cuff. When the pressure is reduced and the highest displacement value (systolic blood pressure value) on the displacement detector becomes equal to the cuff internal pressure, the cuff internal pressure is measured as the systolic blood pressure value, and there is no need to stop blood circulation during measurement. , it is possible to continuously measure systolic blood pressure over a long period of time without restricting or compressing the human body.

Further, the continuous systolic blood pressure measuring device according to the present invention can be said to be highly effective in terms of excellent handling and operability, and accurate and reliable operation.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of a continuous systolic blood pressure measuring device according to the present invention, and FIGS. 2A to C
1 is a graph explaining the measurement principle of the device and showing the relationship between the output of the displacement detector and the internal pressure of the cuff. 1... Displacement detector, 2... Cuff member, 3... Gas pressure chamber, 4... Displacement amplifier, 5... Output polarity discriminator, 6... Cuff internal pressure control circuit, 7... Cuff internal pressure detector, V...Vessel, S...Skin surface.

Claims (1)

[Scope of Claims] 1. Directly attached to the skin surface S at the measurement site in order to detect displacement of the skin surface S due to intravascular pressure, and converting pressure changes (deformation) of the skin surface S into changes in electrical resistance. a displacement detector 1 that outputs the amount of displacement as an electric signal; and a gas pressure chamber 3 around the measurement area to apply pressure to the measurement area from above the displacement detector 1.
a cuff member 2 forming a cuff member 2; cuff internal pressure control means 6 for increasing and decreasing the cuff internal pressure in the cuff member 2 so that the output at the time of the detected systolic blood pressure is 0; is detected by the displacement detector 1, and the cuff internal pressure is controlled by the cuff internal pressure control means 6 in accordance with this output signal, and the maximum displacement value (systolic blood pressure value) in the displacement detector 1 and the cuff internal pressure are controlled. 1. A continuous systolic blood pressure measuring device, characterized in that when the cuff internal pressure becomes equal to the cuff internal pressure, the cuff internal pressure is measured as the systolic blood pressure value.