JPH03221032A - Electronic hemadynamometer - Google Patents

Abstract

PURPOSE:To perform accurate decision of a blood pressure even when a fluctuation in an artery pulse wave is produced by providing a deciding means to decide a maximum and a minimum blood pressure value based on respective two or more temporarily decided blood pressure values. CONSTITUTION:A blood pressure deciding means 5 to decide maximum and minimum blood pressure values Pa and Pb based on respective two or more temporarily decided blood pressure value decides a plurality of temporary blood pressure values responding the maximum and minimum blood pressure values by means of a temporary blood pressure deciding means 12, and decides the maximum and minimum blood pressure values Pa and Pb based on the temporary blood pressure value by means of a blood pressure value deciding means 13. In a temporary blood pressure value responding to a maximum blood pressure, a temporary blood pressure value P1 is determined, based on a value obtained by multiplying a maximum value MAX of an an artery pulse wave valve V by a given definition alpha1, and a temporary blood pressure P2 is determined based on a valve obtained by multiplying the maximum value MAX by a constant alpha2. A blood pressure value being the middle between the temporarily decided blood pressure values P1 and P2 is determined by a blood pressure value computing means 13 to produce the maximum blood pressure Pa. A computing formula for the intermedi ate value is P=P1-(P1- P2)XA, wherein a relation of 0<=A<=1 is established. Decision of the minimum blood pressure Pb is effected in a similar manner described above.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an electronic blood pressure monitor using the oscillometrin method.

[Prior Art] Conventionally, electronic blood pressure monitors using this type of oscillometric method have been used to measure important parts of the human body (for example, the wrist) as shown in FIG.
A cuff band ■ that is wrapped around the cuff band ■, a pressure reduction mechanism 2 that gradually reduces the pressure inside the cuff band I after compressing important parts by pumping air to the cuff band 1, and a pressure reduction mechanism 2 that gradually reduces the pressure inside the cuff band I, and A pressure sensor 3 that converts into an electrical signal, an A/D converter 4 that converts the output of the pressure sensor 3 into A/D as shown in FIG. 6, and a systolic blood pressure value and a Blood pressure determination means 5 consisting of a microcomputer for determining the diastolic blood pressure value
and a blood pressure display means 8 that digitally displays the determined systolic blood pressure value, diastolic blood pressure value, etc. on a liquid crystal display element. The blood pressure determination means 5 also includes an arterial pulse wave value extraction means 6a for extracting the arterial pulse wave value V, a cuff pressure value extraction means 6b for detecting the cuff pressure value P, and an arterial pulse wave value extraction means 6b for detecting the cuff pressure value P. The blood pressure determination means 7 determines the systolic blood pressure value Pa and the diastolic blood pressure MPb based on the changes, and the controller 9 controls the operation timing of each means 6.
In the figure, 10 is a switch for instructing power on/off, pressurization setting, measurement start/end, etc.

FIG. 7 shows an example of a blood pressure determination method using the oscillometric method, showing the arterial pulse wave value V extracted by the arterial pulse wave value extraction means 6a and the cuff pressure value extracted by the cuff pressure value extraction means 6b. The maximum value MAX of the arterial pulse wave value V is determined from the pressure value P, and predetermined constants α, β (0
The cuff pressure value P corresponding to the arterial pulse wave value V that is close to the value multiplied by <α, β x 1) is determined to be the systolic blood pressure value P and the diastolic blood pressure value PL.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional example, the arterial pulse wave value V
When there are fluctuations as shown in FIG. 8 (for example, multiple maximum values), the systolic blood pressure value Pa is set to P or Plo, and the diastolic blood pressure value Pb is set to P2 or P2''. There was a problem in that the blood pressure values displayed were different depending on the location.

The present invention has been made in view of the above points, and its object is to provide an electronic sphygmomanometer that can accurately determine blood pressure even if there are fluctuations in arterial pulse wave values.

[Means for Solving the Problems] The electronic blood pressure monitor of the present invention detects arterial pulse waves of important parts of the human body and measures blood pressure values based on changes in the pulse wave waveform. The blood pressure determining means is configured to determine the systolic blood pressure value and the diastolic blood pressure value, respectively, based on two or more temporarily determined blood pressure values.

[Function J] The present invention is configured as described above, and in an electronic blood pressure monitor using an oscillometric method, the systolic blood pressure value and the diastolic blood pressure value are each determined based on two or more provisionally determined blood pressure values. A blood pressure determining means is formed in the blood pressure system, and blood pressure can be determined accurately even if there are fluctuations in the arterial pulse wave value.

[Embodiment] Fig. 1 shows an embodiment of the present invention, which is similar to the conventional example in which arterial pulse waves of important parts of the human body are detected and blood pressure values are measured based on changes in the pulse wave waveform. In the electronic blood pressure monitor using the oscillometric method, the blood pressure determination means 5 is formed to determine the systolic blood pressure value Pa and the diastolic blood pressure value Pb, respectively, based on two or more temporarily determined blood pressure values. In the embodiment, the low blood pressure value determining means 12 calculates a plurality of low blood pressure values corresponding to the systolic blood pressure, and also calculates a plurality of low blood pressure values corresponding to the diastolic blood pressure, and the blood pressure value determining means 1
In step 3, a high blood pressure value Pa and a diastolic blood pressure value pb are determined based on a plurality of low blood pressure values.

Figure 2 shows a method for obtaining two hypotension values corresponding to the systolic blood pressure.The hypotension value P is calculated based on the value obtained by multiplying the maximum value MAX of the arterial pulse wave value V by a predetermined constant α1. The low blood pressure value P2 is determined based on the value obtained by multiplying the maximum value MAX by a constant α2. Here, MAXX
α1 is a value lower than the fluctuation of arterial pulse wave value V, MAXxα2
α1. so that it has a high value. When α2 is set, PI,
P2 is uniquely determined. It goes without saying that the diastolic blood pressure value pb is determined in the same manner.

Figure 3 shows the systolic blood pressure pb based on the low blood pressure values P, , P2.
This shows an example of a method for determining the blood pressure value Pa, in which a blood pressure value between the blood pressure values P, P2 tentatively determined by the hypotension value determination means 12 is determined by the blood pressure value calculation means 13 and set as the systolic blood pressure value Pa. , the diastolic blood pressure value pb are similarly determined.

In the present embodiment, the intermediate value is calculated as follows: P=P+ (PI P2)XA, where O≦A≦1. Note that A is a coefficient indicating the position of P, and when A=O, P=P, and when A=1, P=P2.

FIG. 4 shows still another embodiment, in which the difference W (= P
The blood pressure value calculation means 13 of the blood pressure determination means 5 is configured to calculate the systolic blood pressure value Pa and the diastolic blood pressure value pb based on the systolic blood pressure value P a = P l (B X W + C)
However, B and C can be calculated using coefficient formulas; another example is the systolic blood pressure value P a = P 1 (D x W / M
(A X + E) However, there is a method of finding D and E using coefficient calculation formulas.

Note that the second term on the right side of the above two examples is a correction term for the temporary blood pressure value P, and uses the difference W between the temporary blood pressure values PI and P2 as a variable.

[Effects of the Invention] The present invention is configured as described above, and in an electronic blood pressure monitor using an oscillometric method, the systolic blood pressure value and the diastolic blood pressure value are each determined based on two or more temporarily determined blood pressure values. The blood pressure determining means is formed in such a manner that accurate blood pressure determination can be performed even if there are fluctuations in the arterial pulse wave value.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of one embodiment of the present invention, FIGS. 2 and 3 are explanatory diagrams of the same operation as above, FIG. 4 is an explanatory diagram of operation of another embodiment, and FIG. 5 is a schematic configuration diagram of a conventional example. 6 to 8 are explanatory views of the same operation as above. 1 is a cuff band, 2 is a pressure adjustment mechanism, 3 is a pressure sensor, and 4 is A
/D converter, 5 is blood pressure determination means, 6a is arterial pulse wave value extraction means, 6b is cuff pressure value extraction means, 7 is blood pressure value determination means,
8 is a blood pressure display means, 9 is a controller, 10 is a switch, 12 is a provisional blood pressure value determining means, and 13 is a blood pressure value calculation means.

Claims (3)

[Claims] (1) In an electronic sphygmomanometer that detects arterial pulse waves in important parts of the human body and measures blood pressure values based on changes in the pulse wave waveform, the systolic blood pressure value and the diastolic blood pressure value are each measured using two or more An electronic blood pressure monitor characterized in that a blood pressure determination means is formed to make a determination based on a provisionally determined blood pressure value. (2) The electronic sphygmomanometer according to claim 1, characterized in that the blood pressure determining means is formed to obtain a blood pressure value between the tentatively determined blood pressure values and use it as the systolic blood pressure value and the diastolic blood pressure value. (3) The electronic sphygmomanometer according to claim 1, characterized in that the blood pressure determination means is formed to determine the systolic blood pressure value and the diastolic blood pressure value based on the difference between the tentatively determined blood pressure values.