PATIENT MONITORING SYSTEM

• US 20120330112A1
• Filed: 06/19/2012
• Published: 12/27/2012
• Est. Priority Date: 06/21/2011
• Status: Active Grant

• Current Assignee: Masimo Corporation
• Original Assignee: Cercacor Laboratories
• Inventors: Lamego, Marcelo, Kiani, Massi Joe E., Lam, Ken, Dalvi, Cristiano, Vo, Hung
• Granted Patent: US 9,532,722 B2
• Time in Patent Office: Days
• US Class Current: 600/301
• CPC Class Codes: A61B 17/135 inflatable for measuring blood pressure A61B5/022; inflatable pressure pads A61F5/34
• CPC Class Codes: A61B 2560/0214 of power generation or supply
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/002 Monitoring the patient using a local or closed circuit, e.g. in a room or building A61B5/0017 takes precedence
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• 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 5/022 by applying pressure to close blood vessels, e.g. against the skin; Ophthalmodynamometers
• CPC Class Codes: A61B 5/02225 using the oscillometric method
• CPC Class Codes: A61B 5/02233 Occluders specially adapted therefor tourniquets A61B17/132
• CPC Class Codes: A61B 5/0225 the pressure being controlled by electric signals, e.g. derived from Korotkoff sounds
• CPC Class Codes: A61B 5/0235 Valves specially adapted therefor
• CPC Class Codes: A61B 5/222 combined with detection or measurement of physiological parameters, e.g. heart rate
• CPC Class Codes: A61B 5/7221 Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence
• CPC Class Codes: A61B 5/7225 Details of analog processing, e.g. isolation amplifier, gain or sensitivity adjustment, filtering, baseline or drift compensation A61B5/30, A61B5/316 take precedence; transformers for specific applications H01F38/00; amplifiers H03F
• CPC Class Codes: A61B 5/725 using specific filters therefor, e.g. Kalman or adaptive filters A61B5/316 take precedence
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: G06N 7/01 Probabilistic graphical models, e.g. probabilistic networks
• CPC Class Codes: G16H 40/63 for local operation

Abstract

A patient monitoring system includes an inflatable cuff, a gas reservoir containing a compressed gas, and a sensor. When the inflatable cuff is coupled to a wearer, the gas reservoir supplies gas to the inflatable cuff to inflate the inflatable cuff via gas pathways. As the inflatable cuff inflates, a patient monitor can receive blood pressure data from the sensor and use the blood pressure data to determine the blood pressure of the wearer. The patient monitor can also receive blood pressure data during deflation of the inflatable cuff to determine the blood pressure of the wearer.

Claims

1. A blood pressure monitoring system wearable by a monitored patient, the system comprising:

a housing;

an inflatable cuff configured to encompass a limb of a monitored patient;

a removable gas reservoir storing pressurized gas;

a chamber positioning the gas reservoir;

a gas pathway between the gas reservoir and the inflatable cuff operable to inflate and deflate the cuff using the pressurized gas;

at least one sensor outputting a signal responsive to a pressure of the gas inside the cuff; and

a processing device configured to receive said signal from said at least one sensor, process said signal and determine one or more blood pressure measurements during at least one of inflation and deflation;

wherein said housing is operably associated with said chamber and said cuff to allow said blood pressure monitoring system to worn on said limb of said monitored patient.

2. The system of claim 1, wherein said processing device comprises a monitor and further comprising a housing operably associated with said processing device to allow said processing device to also be worn on said limb.

3. The system of claim 1, wherein said processing device comprises a personal computing device.

4. The system of claim 1, wherein said processing device comprises a phone executing one or more applications capable of said processing and said determining.

5. The system of claim 1, wherein said processing device controls said inflation and said deflation of said cuff through communication with one or more valves in said gas pathway.

6. The system of claim 1, wherein said processing device determines the blood pressure measurements during inflation.

7. The system of claim 6, wherein said processing device determines a systolic pressure as a magnitude oscillation of the signal and a diastolic pressure as a slope of the signal prior to the magnitude oscillation.

8. The system of claim 7, wherein the magnitude oscillation is the largest magnitude oscillation of the signal during inflation and the slope is the largest slope of the signal prior to the largest magnitude oscillation.

9. The system of claim 1, wherein said processing device determines the blood pressure measurements during deflation.

10. The system of claim 9, wherein said processing device determines a systolic pressure as a pressure of the inflatable cuff corresponding to a first slope of the signal prior to a magnitude oscillation and a diastolic pressure as a pressure of the inflatable cuff corresponding to a second slope of the signal following the magnitude oscillation.

11. The system of claim 10, wherein the magnitude oscillation is the largest magnitude oscillation of the signal during deflation, the first slope is the largest slope of the signal prior to the largest magnitude oscillation, and the second slope is the largest slope of the signal following the largest magnitude oscillation.

12. The system of claim 1, wherein said processing device is further configured to:

determine the one or more blood pressure measurements during inflation;

assign a confidence level to the one or more blood pressure measurement;

determine whether the confidence level is greater than a threshold confidence level; and

upon determining that the confidence level is not greater than the threshold confidence level, determine additional one or more blood pressure measurements during deflation.

13. The system of claim 1, wherein said processing device implements a measurement protocol.

14. The system of claim 13, wherein said measurement protocol includes periodic measurements.

15. The system of claim 14, wherein said measurement protocol monitors other physiological parameters and initiates a blood pressure measurement when other physiological parameters exhibit a predetermined behavior.

16. The system of claim 14, wherein the other physiological parameter responsive to oxygen saturation.

17. The system of claim 1, wherein said processing device communicates with electronics associated with said gas reservoir

18. The system of claim 17, wherein the electronics associated with the gas reservoir indicate whether the gas reservoir is authorized.

19. The system of claim 17, wherein the electronics associated with the gas reservoir indicate gas reservoir usage.

20. The system of claim 19, wherein indicate updated data responsive to usage is written to the electronics associated with said gas reservoir.

21. The system of claim 17, wherein the electronics associated with the gas reservoir indicate reservoir characteristics.

22. The system of claim 1, wherein said processing device is configured to display of waveform on a display device.

23. The system of claim 22, wherein the waveform is responsive to arterial pulse.

24. The system of claim 22, wherein the display device is multi-lingual.

25. The system of claim 22, wherein the display device includes a wellness indicator.

26. A method of determining one or more blood pressure measurements, the method comprising:

determining one or more blood pressure measurements during at least one of inflation and deflation of an inflatable cuff, wherein determining the one or more blood pressure measurements during inflation comprises;

inflating an inflatable cuff connected to an arm of a patient using a replaceable gas reservoir of a portable inflation system,

receiving a signal from a sensor indicative of a pressure inside the inflatable cuff,

filtering the signal,

identifying a maximum magnitude of the filtered signal during inflation of the inflatable cuff, and

associating a pressure of the inflatable cuff during approximately the identified maximum magnitude with a first systolic pressure;

wherein determining the one or more blood pressure measurements during deflation comprises;

deflating an inflated inflatable cuff connected to the arm of the patient, wherein the inflatable cuff is inflated using the replaceable gas reservoir of the portable inflation system,

receiving a signal from a sensor indicative of a pressure inside the inflatable cuff,

filtering the signal,

identifying a maximum magnitude of the filtered signal during deflation of the inflatable cuff, a maximum slope of the filtered signal prior to the maximum magnitude, and a maximum slope of the filtered signal following the maximum magnitude, and

associating a pressure of the inflatable cuff during approximately the identified maximum slope of the filtered signal prior to the maximum magnitude with a second systolic pressure; and

outputting at least one of the first systolic pressure and the second systolic pressure to a display device.

27. The method of claim 26, further comprising:

determining the one or more blood pressure measurements during inflation of the inflatable cuff;

assigning a confidence level to the one or more blood pressure measurements;

determining whether the confidence level is greater than a threshold confidence level; and

upon determining that the confidence level is not greater than the threshold confidence level, determining additional one or more blood pressure measurements during deflation of the inflatable cuff;

28. The method of claim 26, further comprising:

determining whether the pressure within the replaceable gas reservoir is greater than a threshold pressure level; and

replacing the replaceable gas reservoir when the pressure is not greater than the threshold pressure level.

29. The method of claim 26, further comprising communicating with electronics of the replaceable gas reservoir.

30. The method of claim 29, wherein the electronics indicate whether the replaceable gas reservoir is authorized.

31. The method of claim 29, wherein the electronics indicate usage of the replaceable gas reservoir.

32. The method of claim 29, wherein updated data responsive to usage of the replaceable gas reservoir is written to the electronics of the replaceable gas reservoir.

33. The method of claim 29, wherein the electronics associated with the gas reservoir indicate reservoir characteristics.

34. The method of claim 29, further comprising displaying a waveform of the signal on a display device.