Techniques for obtaining information associated with an individual's blood pressure including specifically a stat mode technique

• US 4,699,151 A
• Filed: 11/13/1986
• Issued: 10/13/1987
• Est. Priority Date: 12/21/1984
• Status: Expired due to Fees

• Current Assignee: Baxter Travenol Laboratories Incorporated
• Original Assignee: Baxter Travenol Laboratories Incorporated
• Inventors: Link, William T.
• Primary Examiner(s): Recla, Henry J.
• Assistant Examiner(s): Sykes, Angela D.
• Application Number:
  US06/929,897
• Time in Patent Office: 334 Days
• Field of Search: 128/672, 128/677, 128/680-683, 128/687-688
• US Class Current: 600/494
• CPC Class Codes: A61B 5/02116 of pulse wave amplitude A61B5/02225 takes precedence
• CPC Class Codes: A61B 5/022 by applying pressure to close blood vessels, e.g. against the skin; Ophthalmodynamometers
• CPC Class Codes: A61B 5/7239 using differentiation including higher order derivatives

Abstract

Techniques for determining different parameters associated with an individual'"'"'s blood pressure in a non-invasive manner are disclosed herein. These techniques include (1) generating a blood pressure waveform corresponding to the individual'"'"'s actual waveform, whereby the mean pressure of the individual can be readily calculated, (2) generating a transformation curve unique to the patient from his diastolic and systolic pressures and his cuff pulses, (3) successively monitoring certain parameters of the patient'"'"'s blood pressure including his systolic and diastolic pressures over closely spaced intervals of time without having to subject the patient to cuff pressures much greater than his diastolic pressure, other than initially or not at all utilizing what is referred to as a stat mode, and (4) measuring a patient'"'"'s diastolic and systolic blood pressures at any given instance without ever having to subject the patient to cuff pressures much greater than his diastolic pressure.

Claims

1. A non-invasive method of providing a waveform approximating the actual blood pressure pulse in a particular artery of a given mammal over a specific period of time during which a number of such pulses successively occur, each having diastolic and systolic pressure points, one edge defining a systolic rise and a second edge including a diastolic decline, said method comprising the steps of:

(a) determining by non-invasive means

(i) the diastolic and systolic pressure point of said actual blood pressure pulse,

(ii) the beginning and end points of said actual blood pressure pulse, and

(iii) a plurality of intermediate pressure points on said actual blood pressure pulse at different fixed points in time prior to the end point of said pulse, at least some of said intermediate pressure points being located on the diastolic decline of said actual blood pressure pulse and all of said intermediate points being located on a positively or negatively sloping part of said actual pulse but not a part of said actual pulse have zero slope; and

(b) using said diastolic and systolic points, said beginning and end points and said intermediate points, graphically providing a waveform having

(i) minimum and maximum amplitude points corresponding to said diastolic and systolic points, respectively,

(ii) beginning and end points corresponding to the beginning and end points of said pulse,

(iii) a plurality of intermediate points respectively corresponding to the intermediate points of said pulse.

2. A method according to claim 1 wherein only such diastolic and systolic points, said beginning and end points and said intermediate points of said actual blood pressure pulse are used to graphically provide said waveform.

3. A method according to claim 1 including the step of determining the mean value of said waveform whereby to provide an approximated mean value for said actual blood pressure pulse.

4. A method according to claim 1 including the step of determining the blood pressure constant of said waveform whereby to provide an approximated blood pressure constant for said actual blood pressure pulse.

5. A method according to claim 1 wherein some of said intermediate points are located on the systolic rise of said actual blood pressure pulse and also along the segment of said actual pulse between its systolic rise and diastolic decline.

6. A non-invasive method of providing a waveform approximating the actual blood pressure pulse in a particular artery of a given mammal over a specific period of time during which a number of such pulses successively occur, each having diastolic and systolic pressure points, a back edge defining a systolic rise and a front edge including a diastolic decline, said method comprising the steps of:

(a) determining by non-invasive means

(i) the diastolic and systolic pressure points of said actual blood pressure pulse,

(ii) the beginning and end points of said actual blood pressure pulse, and

(iii) a plurality of intermediate pressure points on said actual blood pressure pulse at different fixed points in time on its diastolic decline prior to the end point of said pulse;

(b) using said diastolic and systolic points, said beginning and end points and said intermediate points, graphically providing a waveform having

(i) minimum and maximum amplitude points corresponding to said diastolic and systolic points, respectively,

(ii) beginning and end points corresponding to the beginning and end points of said pulse,

(iii) a plurality of intermediate points respectively corresponding to the intermediate points of said pulse and a front edge defined by the end point of the actual pulse and its intermediate points,

(iv) a back edge defined by the beginning point and the maximum amplitude point of the actual pulse; and

(c) whereby said graphically provided waveform approximates the actual blood pressure waveform in configuration and mean value.

7. A non-invasive method of providing a waveform approximating the actual blood pressure pulse in a particular artery of a given mammal over a specific period of time during which a number of such pulses successively occur, each having diastolic and systolic pressure points, a front edge including a diastolic decline and a front edge serving as a systolic rise, said method comprising the steps of:

(a) determining by non-invasive means

(i) the diastolic and systolic pressure points of said actual blood pressure pulse,

(ii) the beginning and end points of said actual blood pressure pulse, and

(iii) an intermediate pressure point on said actual blood pressure pulse at a fixed point in time on its diastolic decline prior to the end point of said pulse; and

(b) providing a waveform having minimum and maximum amplitude points corresponding graphically to the diastolic and systolic points of said actual blood pressure pulse, beginning and end points corresponding graphically to the beginning and end points of said pulse, a front edge extending from the end point of the waveform to a second point corresponding graphically to said intermediate pressure point and a back edge extending from the beginning point of the waveform to the said maximum amplitude point, whereby said waveform approximates said actual blood pressure pulse.

8. A non-invasive method of graphically plotting within a two-axis cartesian coordinate system, where one axis represents pressure and the other represents time, a pressure versus time waveform approximating the actual blood pressure pulse in a particular artery of a given mammal over a specific period of time during which a number of such pulses successively occur, each having diastolic and systolic pressure points, a front edge including a diastolic decline, a back edge serving as a systolic rise and a dichrotic notch there between, said method comprising the steps of:

(a) determining by non-invasive means the diastolic and systolic pressure points of said actual blood pressure pulse and, using these pressure points as the minimum and maximum amplitudes of the waveform, graphically plotting a first line and a first point within said coordinate system representing the minimum and maximum pressures of said waveform, respectively;

(b) determining by non-invasive means the beginning and end points of said actual blood pressure pulse and, using these end points as the end points of said waveform, graphically plotting the beginning and end points of said waveform on said first line within the coordinate system;

(c) determining by non-invasive means intermediate pressure points on said actual blood pressure pulse at a number of fixed points in time along its diastolic taper prior to the end of said pulse and, using these intermediate pressure points as intermediate pressure points on said waveform at the same fixed points in time prior to the end point of said waveform, plotting said last-mentioned intermediate pressure points within said coordinate system; and

(d) graphically providing within said coordinate system a second line defined by the end and intermediate points of said waveform and a third line through said beginning point of said waveform and said first point, whereby to graphically complete said waveform except for the space between said second and third lines such that said third line corresponds to the systolic rise of said actual blood pressure pulse, said second line corresponds to the diastolic decline of the actual pulse and said space corresponds to the dichrotic notch of said actual pulse.

9. A non-invasive apparatus for providing a waveform approximating the actual blood pressure pulse in a particular artery of a given mammal over a specific period of time during which a number of such pulses successively occur, each having diastolic and systolic pressure points, a leading edge defining a systolic rise and a trailing edge including a diastolic taper, said apparatus comprising:

(a) means for determining by non-invasive means

(i) the diastolic and systolic pressure points of said actual blood pressure pulse,

(ii) the beginning and end points of said actual blood pressure pulse, and

(iii) a plurality of intermediate pressure points on said actual blood pressure pulse at different fixed points in time prior to the end point of said pulse;

at least some of said intermediate pressure points being located on the diastolic decline of said actual blood pressure pulse and all of said intermediate points being located on a positively or negatively sloping part of said actual pulse but not a part of said actual pulse have zero slope; and

(b) means responsive to said diastolic and systolic points, said beginning and end points and said intermediate points, for graphically providing a waveform having

(i) minimum and maximum amplitude points corresponding to said diastolic and systolic prints, respectively,

(ii) beginning and end points corresponding to the beginning and end points of said pulse, and

(iii) a plurality of intermediate points respectively corresponding to the intermediate points of said pulse.

10. An apparatus according to claim 9 wherein said providing means uses only such diastolic and systolic points, said beginning and end points and said intermediate points of said actual blood pressure pulse to graphically provide said waveform.

11. An apparatus according to claim 9 including means for determining the mean value of said waveform whereby to provide an approximated mean value for said actual blood pressure pulse.

12. An apparatus according to claim 9 including means for determining the blood pressure constant of said waveform whereby to provide an approximated blood pressure constant for said actual blood pressure pulse.

13. A non-invasive apparatus for providing a waveform approximating the actual blood pressure pulse in a particular artery of a given mammal over a specific period of time during which a number of such pulses successively occur, each having diastolic and systolic pressure points, a front edge includng diastolic taper and a back edge serving as a systolic rise, said apparatus comprising:

(a) means for determining by non-invasive means

(i) the diastolic and systolic pressure points of said actual blood pressure pulse,

(ii) the beginnng and end points of said actual blood pressure pulse, and

(iii) a plurality of intermediate pressure points on said actual blood pressure pulse at a fixed point in time on its diastolic taper prior to the end point of said pulse; and

(b) means for providing a waveform having minimum and maximum amplitude points corresponding graphically to the diastolic and systolic points of said actual blood pressure pulse, beginning and end points corresponding graphically to the beginning and end point of said pulse, a front edge extending from the end point of the waveform through a series of said second points corresponding graphically to said intermediate pressure points and a leading edge extending from the beginning point of the waveform to the waveforms'"'"' maximum amplitude point.