Blood pressure monitor

• US 7,404,801 B2
• Filed: 04/01/2004
• Issued: 07/29/2008
• Est. Priority Date: 05/15/2003
• Status: Expired due to Fees

• Current Assignee: Quicare, Ltd.
• Original Assignee: Quicare, Ltd.
• Inventors: Wachtenberg, Eyal
• Primary Examiner(s): Marmor, II; Charles A.
• Assistant Examiner(s): Saidi; Anita
• Application Number:
  US10/556,147
• Publication Number:
  US 20060217617A1
• Time in Patent Office: 1,580 Days
• Field of Search: 600/490, 600/500, 600/503, 600/485, 600493-496
• US Class Current: 600/495
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/02241 of small dimensions, e.g. adapted to fingers

Abstract

The present invention provides an automatic blood pressure monitor for measuring the arterial blood pressure at a location on a patient. The automatic monitor of the invention does not require an external pump of any type. The invention uses a propellant supply chamber containing a predetermined quantity of propellant in order to inflate a pressure occluding bladder, thus allowing the measurement to be made. All of the elements comprising the monitor are attached to or are an integral part of a strap, which supports the monitor at the desired location on the patient. The monitor of the invention is inexpensive and simple to operate and can be used by non-professional persons in non-clinical or non-laboratory environments.

Claims

1. An automatic blood pressure monitor for measuring the arterial blood pressure at a location on a patient, said monitor comprising:

a) an inflatable blood flow occluding bladder;

b) a pressure generator for inflating said blood flow occluding bladder;

c) means for deflating said blood flow occluding bladder;

d) means for detecting, computing and producing an output indicative of the pressure in the artery;

e) means for convening said output into visible signals;

f) means for displaying said signals;

g) means for supplying energy to said monitor; and

h) a strap for supporting said monitor at said location on said patient;

characterized in that,

said pressure generator comprises a propellant supply chamber containing a predetermined quantity of propellant, said chamber having an exit valve for releasing said propellant;

said means for deflating said blood flow occluding bladder comprises a permanently open small exit hole of predetermined size in said blood flow occluding bladder, said permanently open small exit hole being valve free;

said energy supply means is necessary only for supplying energy for the operation of said detecting, computing, converting, and display means; and

all of the elements comprising said monitor are attached to or are an integral pan of said strap;

whereupon said predetermined quantity of propellant, the volume of said flow occluding bladder and the ratio of the cross-sectional area of the opening in said exit valve and the cross-sectional area of the valve free exit hole in said blood flow occluding bladder are such that, upon opening said exit valve said propellant flowing into said blood flow occluding bladder will inflate said blood flow occluding bladder to an initial maximum pressure greater than the pressure necessary to occlude the flow of blood at said location, said pressure in said blood flow occluding chamber decreasing from said maximum value, at a predetermined rate, to a value less than the diastolic pressure at said location in said artery as said propellant escapes from said blood flow occluding bladder through said exit hole;

wherein for at least part of the process for measuring the arterial blood pressure, said propellant is flowing into and out of said blood flow occluding bladder simultaneously.

2. An automatic blood pressure monitor according to claim 1, wherein the artery is located either in the arm, the wrist, or the finger.

3. An automatic blood pressure monitor according to claim 1, wherein the strap comprise fastening means and a tongue;

wherein, some of the elements of said monitor are located in/on said strap and the remaining elements of said monitor are located in/on said tongue.

4. An automatic blood pressure monitor according to claim 3, wherein the strap and fastening means can be detached from the tongue.

5. An automatic blood pressure monitor according to claim 4, wherein the strap and fastening means are disposable after one or a limited number of measurements and the tongue is attached to another strap and fastening means and reused.

6. An automatic blood pressure monitor according to claim 1, wherein said monitor is disposable after one or a limited number of measurements.

7. An automatic blood pressure monitor according to claim 1, wherein the means for detecting and producing an output indicative of the pressure in the artery are selected from the group comprising:

a) pressure transducers; and

b) miniature microphones.

8. An automatic blood pressure monitor according to claim 1, wherein means for supplying energy to the detecting, computing, converting, and display means are chosen from the group comprising:

a) batteries; and

b) pre-charged capacitors.

9. An automatic blood pressure monitor according to claim 1, comprising more than one propellant supply chamber each of said propellant supply chambers having an independently opening exit valve.

10. An automatic blood pressure monitor according to claim 1, wherein the propellant supply chamber is supplied separately from said monitor and can be attached to said monitor for making one or more measurements and replaced with another gas supply chamber for making more measurements.

11. An automatic blood pressure monitor according to claim 1 further comprising an intermediate chamber.

12. A method for measuring arterial blood pressure using the automatic blood pressure monitor of claim 11, said method comprising the following steps:

wrapping the strap around the part of the body where the blood pressure is to be measured with the deflated blood flow occluding bladder placed directly on top of the relevant artery;

tightening the strap until it is pressed firmly against the skin and fastening it;

turning on the detecting, computing, converting, and display means;

allowing a predetermined amount of propellant to flow from said supply chamber into the intermediate chamber;

preventing or restricting the flow of propellant from said supply chamber into said intermediate chamber;

opening the valve between said intermediate chamber and said blood flow occluding bladder thus allowing the propellant in the intermediate chamber to flow into said blood flow occluding bladder, initially pressurizing said bladder to a high enough pressure to occlude the flow of blood in the artery;

allowing said gas to escape from said bladder through the valve free exit hole, gradually depressurizing said bladder to a pressure lower than the diastolic and reducing the degree of occlusion of the artery;

optionally regulating the pressure in said bladder by means of a release valve that opens if a predetermined pressure in said bladder is exceeded;

measuring the blood flow oscillations and pressure with the detecting means as said blood flow occluding bladder is gradually depressurized;

analyzing the signals from said detecting means with said computing and converting means;

digitally displaying the systolic and diastolic pressure and, optionally, the pulse rate on said display means; and

removing said swap from the body after the measurement;

wherein for at least part of the process for measuring the arterial blood pressure, said propellant is flowing into and out of said blood flow occluding bladder simultaneously.

13. A method according to claim 12, wherein the step of allowing a predetermined amount of propellant to flow from the supply chamber into the intermediate chamber takes place before the strap is wrapped around the part of the body.

14. A method according to claim 12, wherein preventing the flow of propellant from the supply chamber into the intermediate chamber is implemented by use of a valve and restricting the flow of propellant from said supply chamber into said intermediate chamber is implemented by use of a very small hole between said supply chamber into said intermediate chamber.

15. A method according to claim 12, wherein the step of preventing the flow of propellant from the supply chamber into the intermediate chamber and the step of opening the valve between said intermediate chamber and the blood flow occluding bladder are implemented simultaneously by a single action.

16. A method for measuring arterial blood pressure using the automatic blood pressure monitor of claim 1, said method comprising the following steps:

wrapping the strap around the part of the body where the blood pressure is to be measured with the deflated blood flow occluding bladder placed directly on top of the relevant artery;

tightening the strap until it is pressed firmly against the skin and fastening it;

turning on the detecting, computing, convening, and display means;

opening the exit valve thus allowing the propellant in the supply chamber to flow into said blood flow occluding bladder, initially pressurizing said bladder to a high enough pressure to occlude the flow of blood in the artery;

allowing said gas to escape from said bladder through the valve free exit hole, gradually depressurizing said bladder to a pressure lower than the diastolic and reducing the degree of occlusion of the artery;

measuring the blood flow oscillations and pressure with the detecting means as said blood flow occluding bladder is gradually depressurized;

analyzing the signals from said detecting means with said computing and converting means;

digitally displaying the systolic and diastolic pressure and, optionally, the pulse rate on said display means; and

removing said strap from the body after the measurement;

wherein for at least part of the process of measuring the blood pressure, said propellant is flowing into and out of said blood flow occluding bladder simultaneously.

17. A method for measuring arterial blood pressure according to claim 16, wherein the artery is chosen from the group comprising;

brachial artery, for measurement on the arm;

radial artery, for the wrist; and

digital artery, for measurement on the index finger.

18. An automatic blood pressure monitor for measuring the arterial blood pressure at a location on a patient, said monitor comprising:

a) a pressurized blood flow occluding bladder;

b) means for depressurizing said blood flow occluding bladder;

c) means for detecting, computing and producing an output indicative of the pressure in the artery;

d) means for converting said output into visible signals;

e) means for displaying said signals;

f) means for supplying energy to said monitor;

g) a strap for supporting said monitor at said location on said patient;

characterized in that,

said blood flow occluding bladder comprises an inflatable bladder initially containing a predetermined quantity of gas at a predetermined pressure;

said means for depressurizing said blood flow occluding bladder comprise an exit hole of predetermined size, initially closed by a seal said exit hole of predetermined size being valve free;

said energy supply means is necessary only for supplying energy for the operation of said detecting, computing, converting, and display means; and

all of the elements comprising said monitor are attached to or are an integral part of said strap;

whereupon, on tightening said swap, thereby pressing said blood flow occluding bladder against the skin above said artery, the pressure against the skin is high enough to occlude the blood flow in said artery and upon removing said seal, said pressure in said blood flow occluding bladder decreases at a predetermined rate to a value less than the diastolic pressure at said location in said artery as said gas escapes from said blood flow occluding bladder though said valve free exit hole.

19. An automatic blood pressure monitor according to claim 18, wherein the pressurized blood flow occluding bladder is supplied separately from said monitor and can be attached to said monitor for making a single measurement and replaced with another pressurized blood flow occluding bladder for making another measurement.

20. A method for measuring arterial blood pressure using the automatic blood pressure monitor of claim 18, said method comprising the following steps:

wrapping the strap around the body part where the blood pressure is to be measured with the pressurized blood flow occluding chamber placed directly on top of the relevant artery;

turning on the detecting, converting, and display means;

tightening the strap until said pressurized blood flow occluding chamber is pressed so firmly against the skin that the blood flow in said artery ceases;

fastening said support means;

opening the seal in the blood flow occluding bladder allowing the gas to escape from said bladder through the valve free exit hole in said bladder, gradually depressurizing said bladder and reducing the degree of occlusion of said artery;

measuring the pulse with said detecting means as said blood flow occluding chamber is gradually depressurized;

analyzing the signals from said detecting means with said converting and computing means;

digitally displaying the systolic and diastolic pressure and, optionally, the pulse rate on said display means; and

removing said strap from the body after the measurement is completed.