Restriction of pressure in a cuff for use in sphyghmomanometry

• US 5,447,160 A
• Filed: 07/09/1991
• Issued: 09/05/1995
• Est. Priority Date: 07/11/1990
• Status: Expired due to Fees

• Current Assignee: Instrumentarium Dental Incorporated (Envista Holdings Corporation)
• Original Assignee: Instrumentarium Dental Incorporated (Envista Holdings Corporation)
• Inventors: Kankkunen, Lauri, Rantala, Borje
• Primary Examiner(s): Cohen, Lee S.
• Assistant Examiner(s): Nasser, Jr., Robert L.
• Application Number:
  US08/727,088
• Time in Patent Office: 1,519 Days
• Field of Search: 128/677, 128/680-686
• US Class Current: 600/490
• CPC Class Codes: A61B 5/02141 Details of apparatus construction, e.g. pump units or housings therefor, cuff pressurising systems, arrangements of fluid conduits or circuits A61B5/02233, A61B5/0235 take precedence
• CPC Class Codes: A61B 5/02233 Occluders specially adapted therefor tourniquets A61B17/132
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence

Abstract

An apparatus and a method for restricting to a proper level the pressure increase in cuffs (7) for use in non-invasive automatic sphyghmomanometry and connectable with a common monitor (1). The apparatus comprises a pump (2) and a cuff (7) in communication therewith that can be replaced with another type of cuff. The pressure of the cuff is increased by means of pump" (2), a valve (8) for releasing the pressure out of cuff (7), a pressure-sensing element (12) for monitoring the development of a cuff pressure, an AC/DC signal separator (13) for separating an AC component from a DC component in a signal received from the pressure-sensing element, and a control element (16) for further processing the information received from the signal separator and for controlling the operation of valve (8). The different cuff types require separate pressure-restricting elements (5 and/or 9), whose maximum accepted set pressures differ from each other and which automatically drop the cuff pressure as the pressure exceeds a set level.

Claims

1. A method for restricting to a proper level the pressure increase in first and second cuffs used in sphygmomanometry, said first and second cuffs to be coupled to a monitor and having first and second maximum acceptable pressures respectively, comprising:

placing said first cuff in flow communication with said monitor and placing a first pressure-restricting element in flow communication with said monitor;

inflating said first cuff, said first pressure-restricting element releasing pressure in said first cuff when the pressure in the first cuff is equal to or exceeds said first maximum acceptable pressure;

measuring the blood pressure of a patient using said first cuff;

decoupling said first cuff from flow communication with said monitor;

decoupling said first pressure-restricting element from said monitor after said first cuff has been decoupled and before placing said second cuff in flow communication with said monitor;

placing said second cuff in flow communication with said monitor and placing a second pressure-restricting element in flow communication with said monitor;

inflating said second cuff, said second pressure-restricting element releasing pressure in said second cuff when the pressure in the second cuff is equate to or exceeds said second maximum acceptable pressure;

measuring the blood pressure of a patient using said second cuff;

decoupling said second cuff from flow communication with said monitor; and

decoupling said second pressure-restricting element from said monitor after said second cuff has been decoupled from flow communication with said monitor.

2. The method of claim 1, further comprising:

forming said first cuff integral with said first pressure-restricting element before said first cuff is placed in flow communication with said monitor.

3. The method of claim 1, further comprising:

prefitting said monitor with a third pressure-restricting element corresponding to a third maximum acceptable pressure of a third cuff, said third maximum acceptable pressure being greater than both said first and said second maximum acceptable pressures.

4. The method of claim 1, further comprising:

placing a third cuff in flow communication with said monitor after decoupling said second pressure-restricting element; and

placing a third pressure-restricting element in flow communication with said monitor, said third pressure-restricting element releasing pressure in said third cuff when the pressure in the third cuff is equal to or exceeds a third maximum acceptable pressure.

5. The method of claim 1, wherein said first cuff is suitable for use with adult patients, and said second cuff is suitable for use with children.

6. An apparatus for use in sphygmomanometry, comprising:

a pump and a first cuff in communication therewith and replaceable with a second cuff, the pressure in said first cuff being increased by means of said pump;

a valve means for releasing pressure out of said first cuff;

a pressure-sensing means for monitoring the development of a cuff pressure in said first cuff;

an AC/DC signal separator means for separating an AC component form a DC component in a signal received from the pressure-sensing means; and

a control means for further processing the information received from the signal separator means and for controlling the operation of said valve means;

wherein said first cuff has a first pressure-restricting element associated therewith, and wherein said second cuff has a second pressure-restricting element associated therewith, said first and second pressure-restricting elements having respective first and second maximum acceptable set pressures that differed from each other and that automatically drop the respective cuff pressure as the pressure in the respective cuffs exceeds a set level.

7. An apparatus as set forth in claim 6, wherein said first pressure-restricting element accepts the maximum possible set pressure and is coupled whenever the largest available first cuff is coupled with the apparatus, and wherein said first pressure-restricting element is integral with the apparatus.

8. An apparatus as set forth in claim 7, wherein said second pressure-restricting element, whose maximum accepted set pressure is lower than a pressure accepted by said first cuff connectable with the same apparatus, is coupled with the apparatus during the replacement of said first cuff by said second cuff.

9. An apparatus as set forth in claim 8, wherein said second pressure-restricting element is located in a place which is in flow communication with said second cuff.

10. An apparatus as set forth in claim 6, wherein said first pressure-restricting element is located in a tube extending from said pump or from said valve means to said first cuff, or is located within said first cuff itself.

11. An apparatus as set forth in claim 6, wherein said first pressure-restricting element is located in a tube extending from the first cuff to the first pressure-sensing means.

12. An apparatus as set forth in claim 6, wherein said second pressure-restricting element is located in a separate intermediate element which is fitted between said second cuff and said monitor during the replacement of said first cuff by said second cuff.

13. An apparatus as set forth in claim 6, further comprising a third cuff, each of said first, second and third cuffs being separately coupled with the apparatus.

14. An apparatus as set forth in claim 13, wherein said three cuffs include a cuff for adults, a cuff for children, and cuff for infants.

15. A method for restricting to a proper level the pressure increase in first and second cuffs used in sphygmomanometry, said first and second cuffs to be coupled to a monitor and having first and second maximum acceptable pressures respectively, comprising:

placing said first cuff in flow communication with said monitor and placing a first pressure-restricting element in flow communication with said monitor;

inflating said first cuff, said first pressure-restricting element releasing pressure in said first cuff when the pressure in the first cuff is equal to or exceeds said first maximum acceptable pressure;

measuring the blood pressure of a patient using said first cuff;

decoupling said first cuff from flow communication with said monitor;

placing said second cuff in flow communication with said monitor and placing a second pressure-restricting element in flow communication with said monitor;

inflating said second cuff, said second pressure-restricting element releasing pressure in said second cuff when the pressure in the second cuff is equal to or exceeds said second maximum acceptable pressure;

measuring the blood pressure of a patient using said second cuff;

decoupling said second cuff from flow communication with said monitor; and

said method including the initial step of prefitting said monitor with a third pressure-restricting element corresponding to a third maximum acceptable pressure of a third cuff, said third maximum acceptable pressure being greater than both said first and said second maximum acceptable pressures.