EP-4740852-A1 - PUMP TO ACTUATOR FLOW RATE

EP4740852A1EP 4740852 A1EP4740852 A1EP 4740852A1EP-4740852-A1

Abstract

Proposed concepts thus aim to provide schemes, solutions, concepts, designs, methods and systems pertaining to determining a flow rate from a pump to an actuator of a blood pressure measurement system. In particular, embodiments aim to provide a method determining a flow rate from a pump to an actuator of a blood pressure measurement system. This can be achieved by using a pump operating parameter value which describes an operation of the motor of the pump and a pressure value which is responsive to a pressure inside the actuator.

Inventors

DUINEVELD, PAULUS CORNELIS

Assignees

Koninklijke Philips N.V.

Dates

Publication Date: 20260513
Application Date: 20241111

Claims (15)

A computer-implemented method (100) for determining a flow rate from a pump to an actuator of a blood pressure measurement system, the method comprising: determining a flow rate from the pump to the actuator (110) based on a pump operating parameter value, describing operation of a motor of the pump, and a pressure value corresponding to a pressure inside the actuator.
The computer-implemented method of claim 1, wherein the pump operating parameter value comprises at least one of: pulse width modulation percentage of the motor of the pump; and revolutions per minute of the motor of the pump.
The computer-implemented method of claim 1 or 2, wherein determining the flow rate from the pump to the actuator is further based on at least one of: voltage supplied to the motor of the pump; pump type; pump state of the pump; ambient pressure; altitude of the actuator; and ambient temperature.
The computer-implemented method any of claims 1 to 3, wherein the method further comprises: detecting a measurement issue (620) based on the determined flow rate.
The computer-implemented method of claim 4, wherein the measurement issue comprises at least one of: a partial blockage of a regulating orifice; a full blockage of a regulating orifice; actuator leakage; a partial blockage of a tube coupling the actuator to a measuring device; and a full blockage of a tube coupling the actuator to a measuring device.
The computer-implemented method of claim 4 or 5, wherein detecting the measurement issue is further based on a subject parameter, and preferably wherein a subject parameter comprises at least one of: BMI; weight; height; age; gender; and arm circumference.
The computer-implemented method of any of claims 4 to 6, wherein the method further comprises: generating a control signal (630) based on the determined flow rate and the detected measurement issue.
The computer-implemented method of claim 7, wherein the control signal comprises a control instruction for modifying an operating parameter of the pump, and preferably, wherein the operating parameter comprises at least one of: pulse width modulation percentage of the motor of the pump; revolutions per minute of the motor of the pump; voltage supplied to the motor of the pump; and user feedback.
The computer-implemented method of any of claims 1 to 8, wherein the method further comprises: determining a first volume of fluid supplied to the actuator (720) based on the determined flow rate; determining a second flow rate from the pump to the actuator (715) based on a second pump operating parameter value and a second pressure value, wherein the second pump operating parameter value and the second pressure value describe a different time point to the pump operating parameter value and the pressure value; determining a second volume of fluid supplied to the actuator (725) based on the determined second flow rate; and determining a total volume of fluid supplied to the actuator as a function of pressure value (730) based on the determined first and second volumes of fluid and the first and second pressure values.
The computer-implemented method of claim 9, wherein the blood pressure measurement system comprises a regulating orifice, and wherein the method further comprises: predicting an orifice flow rate through the regulating orifice (740); and adjusting the determined flow rate and/or the determined total volume of fluid as a function of pressure value (750) based on the predicted orifice flow rate.
The computer-implemented method of claim 9 or 10, further comprising determining an actuator compliance value based on the determined total volume of fluid as a function of pressure value and the first and second pressure values.
The computer-implemented method of any of claims 1 to 11, wherein the blood pressure measurement system is a non-invasive blood pressure measurement system.
The computer-implemented method of any of claims 1 to 12, wherein the actuator comprises a shell cuff actuator.
A computer program comprising code for implementing the method of any preceding claim when said program is run on a processor.
A blood pressure measurement system (800) comprising: a pump (810); an actuator (820); and a processor (830) configured to: determine a flow rate from the pump to the actuator based on a pump operating parameter value, describing operation of a motor of the pump, and a pressure value corresponding to a pressure inside the actuator.

Description

FIELD OF THE INVENTION This invention relates to the field of determining a flow rate from a pump to an actuator. BACKGROUND OF THE INVENTION Non-invasive blood pressure measurement technology is known in the art and has the potential to measure with a similar accuracy to more complicated invasive techniques, such as with a catheter. For example, a non-invasive oscillometric blood pressure system measures blood pressure without penetrating the skin. It works by inflating a cuff around a subject's arm, which temporarily stops blood flow in the artery. As the cuff deflates, the system detects oscillations in the arterial wall caused by blood flow, and these oscillations can be analyzed to determine systolic and diastolic blood pressure values. Some non-invasive blood pressure measurement systems involve a shell cuff actuator. A shell cuff actuator includes an inflatable cuff which can wrap around, for example, the upper arm, connected to a small pump and pressure sensor. When activated, the actuator inflates the cuff to thus compress the brachial artery, and during inflation or deflation, the hemodynamic parameters are typically measured. The actuator's precise control over inflation and deflation, combined with sensitive pressure detection, allows for accurate and automated blood pressure readings. To this end, it is useful to know the exact flow rate from a pump to an actuator of a (non-invasive) blood pressure measurement system. SUMMARY OF THE INVENTION The invention is defined by the independent claims. The dependent claims define advantageous embodiments. According to examples in accordance with an aspect of the invention, there is provided a computer-implemented method for determining a flow rate from a pump to an actuator of a blood pressure measurement system. The method comprises: determining a flow rate from the pump to the actuator based on a pump operating parameter value, describing operation of a motor of the pump, and a pressure value corresponding to a pressure inside the actuator. Proposed concepts thus aim to provide schemes, solutions, concepts, designs, methods and systems pertaining to determining a flow rate from a pump to an actuator of a blood pressure measurement system. In particular, embodiments aim to provide a method for determining a flow rate from a pump to an actuator of a blood pressure measurement system by using a pump operating parameter value which describes an operation of the motor of the pump and a pressure value which is responsive to a pressure inside the actuator. In other words, it is proposed that by using these two parameters, the flow rate from the pump to the actuator can be determined. This leverages the fact that the operation of individual pumps is very reproducible. The flow rate can thus be provided using parameters readily available to a standard blood pressure measurement system, e.g., without the need of any extra sensors. By accurately determining the flow rate delivered by the pump to the actuator it is therefore possible to detect potential issues with the measurement system and to improve control of the system to ensure, for example, a constant actuator pressure slope. Ultimately, an improved method for determining a flow rate from a pump to an actuator of a blood pressure measurement system is provided. In some embodiments, the pump operating parameter value comprises at least one of: pulse width modulation percentage of the motor of the pump; and revolutions per minute of the motor of the pump. Both of these pump operating parameter values may be highly effective and efficient parameters to use to help determine the flow rate from the pump to the actuator. In some embodiments, determining the flow rate from the pump to the actuator is further based on at least one of: voltage supplied to the motor of the pump; pump type; pump state of the pump; ambient pressure; altitude of the actuator; and ambient temperature. These may all be useful further parameters to help make the determined flow rate more accurate. In some embodiments, the method further comprises: detecting a measurement issue based on the determined flow rate. Based on the determined flow rate, it may be possible to detect a wide range of issues with the blood pressure measurement system. In some embodiments, the measurement issue comprises at least one of: a partial blockage of a regulating orifice; a full blockage of a regulating orifice; actuator leakage; a partial blockage of a tube coupling the actuator to a measuring device; and a full blockage of a tube coupling the actuator to a measuring device. These may be useful issues to detect as then said issues can be addressed to improve the reliability of the blood pressure measurement system. In some embodiments, detecting the measurement issue is further based on a subject parameter. This may ensure a more accurate detection of measurement issues. In some embodiments, a subject parameter comprises at least one of: BMI; weight; height;