JPH02228940A - Hemadynamometer - Google Patents

Abstract

PURPOSE: To enable precise blood pressure measurement by providing an arm band configured with its width gradually declining to constringe at one end that will comes over the area, under which an artery runs, when wound around the arm; means to inflate and shrink at least a part of the arm band; and blood pressure instrumentation means. CONSTITUTION: Hemopiezometer 10 has slender arm band 12 with side edge 14, 16, and the arm band is divided into two parts 18, 20 at center line 22 which is neither a joint nor a gap. The arm band is fitted with tubes 24, 26, and spherical part 28 is connected to the tube 26 to deliver air to inflate the band and release air for shrinkage thereof. Further, a pressure meter 32 is joined to the tube 24. Thus, the precise blood pressure measurement can be ensured by changing the width of the extending part of arm band and constringing the arm band according to the size of arm to properly constringe an artery.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a blood pressure monitor, and particularly to a blood pressure monitor whose arm cuff can be freely adjusted to suit the thickness of the arm.

[Conventional technology and its problems] Blood pressure is generally measured as follows.

First, a cuff that expands when air is introduced is wrapped around the upper arm (upper arm) where the brachial artery is located. Next, air is pumped into the cuff to inflate it, compressing the brachial artery at a pressure higher than the blood pressure during cardiac systole, and then the air is removed from the cuff to gradually reduce the pressure. While performing this operation, place the stethoscope on the brachial artery below the cuff and make a Korotkoff sound.
listen to rotkofftapping 5ounds). As is well known, the detection of the first Korotkoff sound and the detection when this sound is about to disappear each determine the systolic blood pressure.
ure) and diastolic blood pressure (dlastollc blo
An arm band that indicates the od pressure) is generally used to have a width of approximately 12 cm, regardless of the thickness of the arm. However, in the arms and thighs, there is soft tissue between the blood vessels and the bones, so if you use the same cuff to measure blood pressure in arms of different diameters, the pressure gauges may show the same pressure value. Even if it does, it is known that it is questionable whether this value accurately represents the actual blood pressure. In fact, tests have shown that both systolic blood pressure and diastolic blood pressure have an error of 5 to 10 mm, Hg or more. This error can have a significant impact on determining whether a person has a disease and whether or not treatment should be given.

To eliminate this error, it is necessary to properly occlude the artery. It has been found that to adequately occlude an artery, the width of the extension of the cuff over the artery must be approximately 40% of the circumference of the arm. American Heart Association (AH)
A) recommends that seven armbands of different widths are required to cover arms of various thicknesses from children to adults with an error of plus or minus 5%. To implement this recommendation, when measuring blood pressure, one must first determine the thickness of the arm and then select a cuff with an appropriate width. Such procedures are cumbersome and are therefore not generally carried out. Currently, a standard arm cuff with a width of 12 centimeters is used to measure blood pressure, even if there are errors.

To solve this problem, a blood pressure measuring device has been proposed that automatically compensates for various arm thicknesses using a cuff that can be partially inflated depending on the arm thickness. Such devices are disclosed in U.S. Pat. No. 3,812,844, U.S. Pat.
It is shown in No.5.

By the way, the measurement results will also be inaccurate if the arm cuff is wrapped around the arm in double or triple layers. It has been determined that blood pressure can only be accurately measured if the cuff extension is wrapped around the arm. Therefore, U.S. Patent No. 1,288°130 and U.S. Patent No. 1.857
, No. 567 proposes to inflate only the part wrapped around the arm, rather than inflating the entire cuff.

In addition to the above, U.S. Patent No. 4,501,280 includes
An automated blood pressure measurement system is disclosed that includes appropriate sensors and a microprocessor to automatically measure blood pressure using cuffs of various sizes, from normal sizes to neonatal sizes.

[Means for Solving the Problems, Actions, and Effects] The blood pressure monitor based on the present invention has two parts, one of which has a width that gradually narrows (converges) so that when wrapped around the arm, the blood pressure monitor has two parts. a cuff with a convergent portion that gradually narrows in width to cover an artery; a means for inflating and contracting the bicep;
and means for measuring blood pressure. It is also possible to further provide clamping means for accommodating the excess portion of the cuff that exceeds the circumference of the arm to prevent air from entering this portion.

The method of using the blood pressure monitor based on the present invention is as conventional.
The various detailed elements necessary for its operation are known to those skilled in the art. Therefore, in the following description, these well-known elements are only shown in outline.

[Example] FIG. 1 is a schematic diagram of a first example of a blood pressure monitor based on the present invention. This sphygmomanometer is used by wrapping an extension part, which has a converging part whose width gradually becomes narrower as it goes forward, around the artery in the arm. The width reduction factor is selected to substantially eliminate the error associated with blood pressure measurements obtained using a standard size cuff, ignoring arm thickness. That is, based on the recommendations of the American Heart Association, the width of the extended part of the cuff that covers the brachial artery is set to be approximately 40% of the circumference of the arm for any size arm. . To simplify the description, the following description assumes that the cuff of the blood pressure monitor is wrapped around the brachial artery of the arm.

As shown in FIG. 1, blood pressure monitor 10 includes an elongated cuff 12 having side ends 14 and 16. The cuff 2 is divided into two parts 18 and 20 by a central line 22.

The dotted central line 22 in FIG.
It is only meant to indicate the boundary of 0, and is not a seam or cut in the armband. Attached to cuff 12 are tubes 24 and 2B, or a single tube, as is known in the art. Preferably, tubes 24 and 26 (or a single tube) are provided as close as possible to the apex, which is the distal end of the tapered convergent portion. A spherical portion 28 is connected to the tube 2B. The bulb 28 has appropriate valves 30 for directing air into the cuff 12 to inflate the cuff 12 and for removing air from the cuff 12 to deflate the cuff 12. A known pressure gauge 32 is connected to the tube 24, and blood pressure is measured with this.

As shown in FIG. 1, the side edges 14 and 16 of the convergent portion 20 of the cuff 12 are relatively close together and intersect at a point.

The side edges 14 are inclined from the center line 22, as indicated by the reference numeral 34, and intersect the side edges 1B at an apex 36.

If desired, cuff 12 may be covered with a non-stretchable cover 35, as shown in FIG.

FIG. 2 shows a second embodiment of the blood pressure system according to the present invention. One side 42 of the cuff 4G is covered with stretchable or non-stretchable fabric (matrtx) indicated by the cross lines. The fabric is a relatively rigid woven thin metal or plastic material, and is overlaid and adhered to the surface 42 of the cuff 40. The non-stretch material serves the same function as the non-stretch cloth cover 35 shown in FIG. The cuff 40 is fitted with suitable tubes 44 and 46 (or a single tube) as in the first embodiment.

In this embodiment, the side edges 48 and 50 are both sloped toward each other and meet at an apex 56, as shown at 52 and 54. If desired, the clamping means 5B may be secured to the cuff 40 (or by combining the cuff with a cover). The clamping means 5B has clamping members 60 and 62 that rotate around a fulcrum 64 by applying pressure to the nodle 6G and clamp the cuff 40 as described in detail below.

As shown in FIG. 3, the arm 70 includes a brachial artery 72 and a humerus bone 74. The brachial artery 72 is located approximately 180 degrees of the humerus bone 74.
Therefore, when using the blood pressure monitor of the present invention, the cuff is wrapped around the arm 70 after the apex of the cuff is positioned near the humerus. Then, grip the handle B6 of the clamp 58 to open the clamping members 60 and 82,
The remaining part of the cuff is sandwiched between the clamping members and the remaining part is closed. Therefore, not only is the cuff firmly secured to the arm 70, but when air is directed to the cuff by operation of the bulbous portion 28, only the portion surrounding the arm inflates.

The cuff of the present invention has a width that gradually decreases so that the portion covering the artery always has an appropriate proportion to the circumference of the arm, so it can accurately measure blood pressure on any arm size. be able to. As pointed out earlier, according to the AHA study,
This ratio is approximately 40% of the circumference of the arm, and is achieved by placing the central line 22 between the cuff's image portions 18 and 20 approximately in the middle of the cuff's length. By the way, it is not necessary to keep increasing the width of the cuff, which gradually becomes wider from the apex. If the width is continuously increased by continuing the slope of both ends, the cuff becomes too wide and eventually becomes unwieldy and difficult to handle. It is not necessary to do this, just narrow the width from approximately the center of the armband in the longitudinal direction. For example, the gradually narrowing width shown at 20 in FIG. 1 always covers an artery.

When covering the arm with a convergent part of the cuff that gradually narrows in width, if the apex of the cuff is positioned adjacent to the humerus, the width of the cuff that covers the artery will be the same as that of the arm. Approximately 40% of the circumference is tightened every time.Therefore, using the same blood pressure monitor, it is possible to accurately measure the blood pressure of arms of various sizes, from children to adults.

Although the preferred embodiment of the present invention uses a clamp 58, a structure without a clamp as shown in FIG. By employing a fastener, the cuff can be fixed without any problems. Again, the apex 36 is positioned adjacent to the humerus, the arm is covered with a cuff, and the cuff is secured before blood pressure is measured in the conventional manner.

FIG. 5 shows a third embodiment of the invention. The cuff 71 has an extensible portion 73 and a non-extensible portion 74 wound around the roller 7G. The roller 76 has a protruding clamp mechanism 7B. A hook 80 is hooked onto a receiver 82 attached to the clamp 78 as shown by the dotted line. Wrap the cuff around your arm so that the gradually narrowing extension covers the artery. In the embodiments described above, the width of the cuff narrows linearly, but the change in width does not have to be linear as long as the width of the cuff has a desired ratio to the circumference of the arm. .

[Brief Description of the Drawings] Fig. 1 is a schematic diagram of a blood pressure monitor according to an embodiment of the present invention, Fig. 2 is a plan view of the second embodiment, and Fig. 3 shows a cuff wrapped around the arm. Schematic diagram, FIG. 4 is a sectional view showing a part of the cuff,
FIG. 5 is a schematic diagram of the third embodiment. DESCRIPTION OF SYMBOLS 10... Sphygmomanometer, 12... Bracelet, 22... Center line, 28... Spherical part, 36... Apex, 58... Clamping means, 66... Handle, 80... ··hook,
82...Received. Applicant's agent Patent attorney Takehiko Suzue

Claims (8)

[Claims] (1) (a) A cuff for measuring blood pressure that has a convergent portion whose width is gradually narrowed and is wrapped around the arm, and (b) inflates or deflates at least a portion of the cuff that includes this convergent portion. (c) means for fixing the cuff to the arm with the convergent portion covering the brachial artery; and (d) means connected to the cuff for measuring blood pressure. A blood pressure monitor. (2) The blood pressure monitor according to claim 1, wherein the arm cuff has means for reducing flexibility. (3) The blood pressure monitor according to claim 2, wherein the means for reducing the suppleness of the cuff is a substantially non-stretchable textile cover placed over the cuff. 4. The sphygmomanometer according to claim 2, wherein the means for reducing the flexibility of the cuff is a substantially inextensible material integrally formed with the cuff. (5) The blood pressure monitor according to claim 1, wherein a clamping means is attached to the distal end of the convergent portion. (6) The sphygmomanometer according to claim 5, wherein the clamping means includes a clamping member that pinches the arm cuff that protrudes from the circumference of the arm and prevents the protruding portion from expanding. . (7) The sphygmomanometer according to claim 1, further comprising roller means for accommodating the cuff, and the roller means having clamp means for preventing expansion of the cuff at a portion protruding from the circumference of the arm. (8) The sphygmomanometer according to claim 7, wherein a hook for fixing the cuff to the arm is provided at the distal end of the convergent portion.