CABLE SYSTEM FOR GENERATING SIGNALS FOR DETECTING MOTION AND MEASURING VITAL SIGNS

• US 20170035305A1
• Filed: 10/24/2016
• Published: 02/09/2017
• Est. Priority Date: 05/20/2009
• Status: Active Grant

• Current Assignee: Sotera Wireless Incorporated
• Original Assignee: Sotera Wireless Incorporated
• Inventors: MOON, Jim, McCOMBIE, Devin, DHILLON, Marshal, BANET, Matthew
• Granted Patent: US 10,321,830 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2560/0261 using hydrostatic pressure
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• 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 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/0024 for multiple sensor units attached to the patient, e.g. using a body or personal area network
• CPC Class Codes: A61B 5/0082 adapted for particular medical purposes
• CPC Class Codes: A61B 5/02028 Determining haemodynamic parameters not otherwise provided for, e.g. cardiac contractility or left ventricular ejection fraction
• 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 5/02125 of pulse wave propagation time
• 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 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence
• CPC Class Codes: A61B 5/0285 Measuring or recording phase velocity of blood waves
• CPC Class Codes: A61B 5/0295 using plethysmography, i.e. measuring the variations in the volume of a body part as modified by the circulation of blood therethrough, e.g. impedance plethysmography
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/1116 Determining posture transitions
• CPC Class Codes: A61B 5/1117 Fall detection
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/1122 of movement trajectories
• CPC Class Codes: A61B 5/1123 : Discriminating type of movement, e.g. walking or running A61B5/1116, A61B5/112 take precedence
• CPC Class Codes: A61B 5/14551 : for measuring blood gases
• CPC Class Codes: A61B 5/25 : Bioelectric electrodes therefor
• CPC Class Codes: A61B 5/282 : Holders for multiple electrodes for introduction into the body A61B5/287
• CPC Class Codes: A61B 5/30 : Input circuits therefor
• CPC Class Codes: A61B 5/316 : Modalities, i.e. specific diagnostic methods
• CPC Class Codes: A61B 5/318 : Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/339 : Displays specially adapted therefor
• CPC Class Codes: A61B 5/349 : Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/447 : specially adapted for aiding the prevention of ulcer or pressure sore development, i.e. before the ulcer or sore has developed
• CPC Class Codes: A61B 5/681 : Wristwatch-type devices
• CPC Class Codes: A61B 5/6823 : Trunk, e.g., chest, back, abdomen, hip
• CPC Class Codes: A61B 5/6824 : Arm or wrist
• CPC Class Codes: A61B 5/6826 : Finger
• CPC Class Codes: A61B 5/7207 : of noise induced by motion artifacts
• CPC Class Codes: A61B 5/7239 : using differentiation including higher order derivatives
• CPC Class Codes: A61B 5/7257 : using Fourier transforms
• CPC Class Codes: A61B 5/746 : Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B

Abstract

The invention provides a system and method for measuring vital signs and motion from a patient. The system features: (i) first and second sensors configured to independently generate time-dependent waveforms indicative of one or more contractile properties of the patient'"'"'s heart; and (ii) at least three motion-detecting sensors positioned on the forearm, upper arm, and a body location other than the forearm or upper arm of the patient. Each motion-detecting sensor generates at least one time-dependent motion waveform indicative of motion of the location on the patient'"'"'s body to which it is affixed. A processing component, typically worn on the patient'"'"'s body and featuring a microprocessor, receives the time-dependent waveforms generated by the different sensors and processes them to determine: (i) a pulse transit time calculated using a time difference between features in two separate time-dependent waveforms, (ii) a blood pressure value calculated from the time difference, and (iii) a motion parameter calculated from at least one motion waveform.

Claims

1. A method for measuring vital signs from a patient, comprising:

(a) positioning an optical sensor configured to detect a first time-dependent physiological waveform indicative of one or more contractile properties of the patient'"'"'s heart on a finger of the patient;

(b) positioning a housing on the patient'"'"'s chest, the housing enclosing (i) an integrated circuit configured to operably connect to at least two electrodes and to determine from signals obtained therefrom a time dependent ECG waveform, and (ii) a first accelerometer configured to generate a first set of time-dependent motion waveforms along three orthogonal axes indicative of motions of the patient'"'"'s torso;

(c) positioning at least two electrodes configured to detect electrical signals from the patient'"'"'s body and to operably connect to the integrated circuit;

(d) positioning a second accelerometer on the upper arm of the patient, the second accelerometer configured to generate a second set of time-dependent motion waveforms along three orthogonal axes indicative of motions of the patient'"'"'s upper arm;

(e) positioning a third accelerometer on the lower arm of the patient, the third accelerometer configured to generate a third set of time-dependent motion waveforms along three orthogonal axes indicative of motions of the patient'"'"'s lower arm;

(f) transmitting the first time-dependent physiological waveform, the time dependent ECG waveform, and the first, second, and third sets of time-dependent motion waveforms to a processing component, wherein at least the time dependent ECG waveform, and the first, second, and third time-dependent motion waveforms are transmitted in the form of synchronized, separately resolvable digital data comprising a header indicating the sensor from which the digital data originates,

wherein the processing component receives and collectively processes the first time-dependent physiological waveform, the time dependent ECG waveform, and the first, second, and third sets of time-dependent motion waveforms and determines therefrom for the patient a plurality of vital signs comprising (i) a continuously monitored blood pressure;

(ii) a continuously monitored posture and activity level, (iii) a continuously monitored SpO2, (iv) a continuously monitored pulse rate, and (v) a continuously monitored ECG; and

(g) simultaneously displaying the plurality of vital signs on a patient-specific display component and transmitting the plurality of vital signs to a remote receiver operably connected to a nursing station.

2. A method according to claim 1, wherein the plurality of vital signs further comprises a respiration rate.

3. A method according to claim 1, wherein determining the continuously monitored posture and activity level comprises determining arm height using the second and third sets of time-dependent motion waveforms;

and wherein determining the continuously monitored blood pressure comprises correcting a pulse transit time measurement for variations resulting from the arm height.

4. A method according to claim 1, wherein the method further comprises continuously updating a threshold at which one or more of the plurality of vital signs would signal an alarm condition by setting the alarm threshold for the alarm condition according to the current posture and activity level determined for the patient.