Continuous Non-Invasive Blood Pressure Measurement Apparatus and Methods Providing Automatic Recalibration
First Claim
Patent Images
1. A method for maintaining calibration of a continuous non-invasive blood pressure (CNIBP) measurement system, the method comprising:
- performing a calibration by;
obtaining for a subject a reference blood pressure value, reference CNIBP data and reference pulse wave data, the reference pulse wave data corresponding to one or more reference pulse waves;
calculating and storing coefficients of a CNIBP calculation formula based on the reference blood pressure value and the reference CNIBP data; and
,storing a template comprising information characterizing one or more characteristics of the reference pulse wave data;
subsequently, obtaining subsequent pulse wave data characterizing one or more subsequent pulse waves of the subject and evaluating a recalibration condition comparing the subsequent pulse wave data to the template; and
,if the subsequent pulse wave data and template satisfy the recalibration condition, repeating performing the calibration of the CNIBP measurement system.
0 Assignments
0 Petitions
Accused Products
Abstract
A blood pressure measurement system is configured to perform a calibration automatically when a calibration condition is satisfied. The calibration condition is based upon one or more parameters of pulse waves of a subject. The parameters may include pulse wave area; a time difference between systolic peak and reflected wave peak or dichrotic notch in the pulse wave and a shape of at least a portion of the pulse wave.
175 Citations
54 Claims
-
1. A method for maintaining calibration of a continuous non-invasive blood pressure (CNIBP) measurement system, the method comprising:
-
performing a calibration by; obtaining for a subject a reference blood pressure value, reference CNIBP data and reference pulse wave data, the reference pulse wave data corresponding to one or more reference pulse waves; calculating and storing coefficients of a CNIBP calculation formula based on the reference blood pressure value and the reference CNIBP data; and
,storing a template comprising information characterizing one or more characteristics of the reference pulse wave data; subsequently, obtaining subsequent pulse wave data characterizing one or more subsequent pulse waves of the subject and evaluating a recalibration condition comparing the subsequent pulse wave data to the template; and
,if the subsequent pulse wave data and template satisfy the recalibration condition, repeating performing the calibration of the CNIBP measurement system. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 54)
-
-
39. A method for triggering recalibration of a continuous non-invasive blood pressure (CNIBP) measurement system, the method comprising:
-
obtaining pulse wave data from a subject, the pulse wave data comprising a signal representing amplitude of pulse waves in the subject as a function of time; comparing at least one feature of the pulse wave data to a corresponding reference feature in a stored template, the at least one feature comprising one or more of a first feature, a second feature, a third feature, and a fourth feature of the pulse waves; the first feature comprising a pulse wave area of the pulse waves; the second feature comprising a time difference, Δ
T, between two internal features within the pulse waves;the third feature comprising a pulse wave shape of at least a part of the pulse waves; and
,the fourth feature comprising at least one of an amplitude of the pulse waves and a width of the pulse waves. - View Dependent Claims (40, 41)
-
-
42. Apparatus for continuous non-invasive blood pressure (CNIBP) measurement, the apparatus comprising:
-
a reference blood pressure measurement mechanism; at least one CNIBP sensor having an output signal which varies with a blood pressure of a subject; a CNIBP controller configured to compute a blood pressure of the subject from the output signal according to a CNIBP calculation formula comprising at least one coefficient; wherein the CNIBP controller is configured to trigger the reference blood pressure measurement mechanism to obtain a reference blood pressure and to use the reference blood pressure to determine a new value for the at least one coefficient by; monitoring a pulse wave signal representing pulse waves of the subject; evaluating a recalibration condition comparing pulse waves in the pulse wave signal to a stored template; and
,determining whether the pulse waves and template satisfy the recalibration condition. - View Dependent Claims (43, 44, 45, 46, 47, 48, 49, 50, 51, 52)
-
-
53. Apparatus for triggering recalibration of a continuous non-invasive blood pressure (CNIBP) measurement system, the apparatus comprising:
-
an input for receiving pulse wave data from a subject, the pulse wave data comprising a signal representing amplitude of pulse waves in the subject as a function of time; a processor arranged to execute software instructions which cause the processor to compare at least one feature of the pulse wave data to a corresponding reference feature in a stored template, the at least one feature comprising one or more of a first feature, a second feature, a third feature, and a fourth feature of the pulse waves; the first feature comprising a pulse wave area of the pulse waves; the second feature comprising a time difference, Δ
T, between two internal features within the pulse waves;the third feature comprising a pulse wave shape of at least a part of the pulse waves; and
,the fourth feature comprising at least one of an amplitude of the pulse waves and a width of the pulse waves.
-
Specification