SYSTEMS AND METHODS TO MONITOR REPOSITIONING OF A PATIENT

• US 20170055896A1
• Filed: 08/31/2016
• Published: 03/02/2017
• Est. Priority Date: 08/31/2015
• Status: Active Grant

• Current Assignee: Masimo Corporation
• Original Assignee: Masimo Corporation
• Inventors: Al-Ali, Ammar, Raths, Cornelius
• Granted Patent: US 10,736,518 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2560/0475 Special features of memory means, e.g. removable memory cards
• CPC Class Codes: A61B 2562/0204 Acoustic sensors
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 2562/0223 Magnetic field sensors
• CPC Class Codes: A61B 2562/0271 Thermal or temperature sensors
• CPC Class Codes: A61B 2562/029 Humidity sensors
• CPC Class Codes: A61B 2562/166 the sensor is mounted on a specially adapted printed circuit board
• CPC Class Codes: A61B 5/0004 characterised by the type of physiological signal transmitted
• CPC Class Codes: A61B 5/0008 Temperature signals
• CPC Class Codes: A61B 5/0015 characterised by features of the telemetry system
• 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 5/004 adapted for image acquisition of a particular organ or body part A61B5/0082 takes precedence; arrangements for optical scanning A61B5/0062
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• 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 5/02055 Simultaneously evaluating both cardiovascular condition and temperature
• CPC Class Codes: A61B 5/0245 by using sensing means generating electric signals, i.e. ECG signals
• CPC Class Codes: A61B 5/05 Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves impedance plethysmography A61B5/0295; measuring movement of the entire body or parts thereof A61B5/11; detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof A61B5/24
• CPC Class Codes: A61B 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/1113 : Local tracking of patients, e.g. in a hospital or private home
• 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 5/1121 : Determining geometric values, e.g. centre of rotation or angular range of movement
• CPC Class Codes: A61B 5/1126 : using a particular sensing technique
• CPC Class Codes: A61B 5/113 : occurring during breathing
• CPC Class Codes: A61B 5/14551 : for measuring blood gases
• CPC Class Codes: A61B 5/14552 : Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/25 : Bioelectric electrodes therefor
• CPC Class Codes: A61B 5/318 : Heart-related electrical modalities, e.g. electrocardiography [ECG]
• 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 5/6801 : specially adapted to be attached to or worn on the body surface
• CPC Class Codes: A61B 5/6823 : Trunk, e.g., chest, back, abdomen, hip
• CPC Class Codes: A61B 5/6833 : Adhesive patches
• CPC Class Codes: A61B 5/68335 : including release sheets or liners
• CPC Class Codes: A61B 5/7264 : Classification of physiological signals or data, e.g. using neural networks, statistical classifiers, expert systems or fuzzy systems neural networks per se G06N3/00; expert systems per se G06N5/00
• CPC Class Codes: A61B 5/7275 : Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61B 5/7282 : Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence
• CPC Class Codes: A61B 5/742 : using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61B 5/743 : Displaying an image simultaneously with additional graphical information, e.g. symbols, charts, function plots
• 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
• CPC Class Codes: A61G 2203/32 : for force
• CPC Class Codes: A61G 2203/36 : for motion
• CPC Class Codes: A61G 2203/42 : for inclination
• CPC Class Codes: A61G 2203/46 : for temperature
• CPC Class Codes: A61G 7/057 : Arrangements for preventing bed-sores or for supporting patients with burns, e.g. mattresses specially adapted therefor ventilation openings in mattresses A47C21/042; pneumatic or hydraulic mattresses A47C27/08
• CPC Class Codes: G01K 1/16 : Special arrangements for conducting heat from the object to the sensitive element
• CPC Class Codes: G01K 13/20 : Clinical contact thermometers for use with humans or animals
• CPC Class Codes: G16H 50/30 : for calculating health indices; for individual health risk assessment

Abstract

A patient monitoring system to help manage a patient that is at risk of forming one or more pressure ulcers is disclosed. The system includes a patient-worn wireless sensor that senses the patient'"'"'s orientation and wirelessly transmits information indicative of the sensed orientation to a patient monitor. The patient monitor receives, stores, and processes the transmitted information. It also displays and transmits information indicative of the patient'"'"'s orientation to help caregivers manage the patient'"'"'s risk of formation of one or more pressure ulcers. The patient monitor detects patient turns from one position to another. The system can identify the present orientation of the patient and determine how long the patient has been in the present orientation. If the patient remains in an orientation beyond a predefined duration, the system can notify the patient and/or caretakers that the patient is due to be repositioned.

Claims

1. A system for monitoring an orientation of a patient to reduce a risk of the patient developing a pressure ulcer, the system comprising:

a sensor including an accelerometer, a processor, and a first wireless transceiver, said sensor configured to output a signal responsive to acceleration, said acceleration indicative of a possible change in an orientation of said patient when said sensor is worn by said patient; and

a patient monitor comprising a signal processor, a memory device, a storage device, and a second wireless transceiver, said second wireless transceiver is configured to receive said signal, and said signal processor is configured to process said signal to determine whether said possible change corresponds to an actual change in said orientation, when said actual change has occurred, configured to record a patient turn event, to compare said patient turn event with a patient turn protocol, and when said possible change is not said actual change and no patient turn event occurs according to the patient turn protocol, said patient monitor is configured to notify a caregiver of a patient turn protocol violation,

wherein said signal processor configured to determine whether said possible change corresponds to said actual change includes being configured to determine a difference between said orientation at a previous time and at a current time based at least on said signal, and when said difference is above a threshold, recording said patient turn event.

2. The system of claim 1, wherein said signal processor of said patient monitor is further configured to reset a patient orientation duration timer when said processor records said patient turn event.

3. The system of claim 1, comprising a third wireless transceiver, said third wireless transceiver configured to receive said signal from said sensor and to transmit said signal to said patient monitor.

4. The system of claim 3, comprising a power supply for said third wireless transceiver different from a power supply for said sensor or said patient monitor.

5. The system of claim 1, wherein said sensor comprises a gyroscope.

6. The system of claim 1, wherein said sensor comprises an acoustic sensor.

7. The system of claim 1, wherein said sensor comprises a temperature sensor.

8. The system of claim 1, wherein said sensor comprises an ECG sensor.

9. The system of claim 1, wherein said sensor comprises one or more of an acoustic sensor, a temperature sensor and an ECG sensor.

10. The system of claim 1, wherein said patient monitor is configured to determine measurements of one or more of the following parameters:

an acceleration, an angular velocity, a magnetic field, a respiration rate, a temperature, an impedance value, a moisture value, an oximetry value and an electrocardiogram.

11. A method to determine a patient'"'"'s change in orientation by monitoring patient movement with a patient-worn sensor, communicating a signal indicative of said monitoring to a processing device, receiving said signal at said processing device, and processing using a signal processor said signal to determine whether said change in orientation has occurred, said patient-worn sensor including an accelerometer, a processor, and a first wireless transceiver, said processing device including said signal processor, a memory device, a storage device, and a second wireless transceiver, said method comprising:

receiving, from said patient-worn sensor, information indicative of a patient'"'"'s orientation at a first time period;

receiving, from said patient-worn sensor, information indicative of the patient'"'"'s orientation at a second time period, wherein said first time period is prior to, and in close temporal proximity to said second time period; and

with said signal processor, processing said information including;

combining said received information to form a time window of patient orientation information, wherein said time window spans said first and second time periods;

dividing said time window into segments, wherein each segment has a segment value indicative of said patient'"'"'s orientation;

determining a difference between said segment values;

when said determined difference exceeds a predetermined threshold, determining a patient turn event has occurred;

classifying said patient turn event;

reporting said classified patient turn event to a caregiver; and

resetting a timer associated with a patient turn protocol.

12. The method of claim 11, comprising determining whether the patient has remained in an orientation for a period of time that exceeds a predetermined maximum duration and transmitting an alert in response to said determination.

13. The method of claim 11, wherein said receiving information indicative of said patient'"'"'s orientation at said first and second time periods comprises receiving acceleration data at said first and second time periods.

14. The method of claim 13, wherein said acceleration data includes a roll axis value and a pitch axis value.

15. The method of claim 14, comprising determining a change in a longitudinal axis of said patient responsive to said roll axis value and determining a change relative to an axis aligned with hips of the patient responsive to said pitch axis value.

16. The method of claim 11, wherein said classifying said patient turn event comprises comparing said segment values with a table of profiles of patient orientation change actions.

17. The method of claim 11, wherein each of said segment values comprises a roll axis median and a pitch axis median, and wherein said roll axis median and said pitch axis median are in units of degrees ranging from −

180 degrees to +180 degrees.

18. The method of claim 17, wherein said predetermined threshold of said difference between said segment values is 45 degrees.

19. A method to determine a patient'"'"'s change in orientation by monitoring patient movement with a patient-worn sensor, communicating a signal indicative of said monitoring to a processing device, receiving said signal at said processing device, and processing using a signal processor said signal to determine whether said change in orientation has occurred, said patient-worn sensor including an accelerometer, a processor, and a first wireless transceiver, said processing device including said signal processor, a memory device, a storage device, and a second wireless transceiver, said method comprising:

receiving, from said patient-worn sensor, information indicative of a patient'"'"'s orientation at a current time period, said information including acceleration data having a roll axis value and a pitch axis value;

with said signal processor, electronically processing said information including;

extracting, from said storage device, information indicative of the patient'"'"'s orientation at a previous time period, said previous time period is prior to, and in close temporal proximity to said current time period;

combining said current and previous orientation information to form a time window of patient orientation information, said time window spanning said previous and current time periods;

segmenting said time window into at least two segments;

determining, for each segment, a segment value, each segment value comprising a roll component and a pitch component;

comparing, pairwise, said determined segment values;

determining, for each pairwise comparison whether a patient turn event has occurred;

in response to a determined patient turn event occurrence classifying said determined turn event;

identifying a most frequently classified turn event;

reporting, as said patient'"'"'s new orientation, said most frequently classified turn event; and

resetting an orientation duration timer.

20. The method of claim 19, wherein said received information comprises a plurality of samples, sampled at a sampling rate.

21. The method of claim 20, wherein said sampling rate is configured to be between approximately 10 Hz and approximately 100 Hz.

22. The method of claim 20, wherein said sampling rate is configured to be between approximately 5 Hz and approximately 40 Hz.

23. The method of claim 19, wherein processing said information further comprises:

determining a roll axis orientation indicative of said patient'"'"'s orientation relative to a longitudinal axis of the patient; and

determining a pitch axis orientation indicative of said patient'"'"'s orientation relative to an axis aligned with hips of the patient.

24. The method of claim 19, wherein said received information comprises a plurality of samples, sampled at a sampling rate, and wherein processing said information further comprises determining, for each of said plurality of samples, a roll axis value indicative of said patient'"'"'s orientation relative to a longitudinal axis of the patient and a pitch axis value indicative of said patient'"'"'s orientation relative to an axis aligned with hips of the patient.

25. The method of claim 24, wherein determining said roll and pitch axis values includes determining said values in units of degrees ranging from −

180 degrees to +180 degrees.

26. The method of claim 19, wherein determining said segment values comprises determining a roll axis median and a pitch axis median said roll and pitch axis medians in units of degrees ranging from −

180 degrees to +180 degrees.

27. The method of claim 26, wherein comparing said segment values comprises determining a difference between roll axis medians and a difference between pitch axis medians.

28. The method of claim 27, wherein determining whether a patient turn event is indicated comprises determining whether said difference between roll axis medians or said difference between pitch axis medians exceeds a predetermined threshold, when said predetermined threshold is exceeded, a patient turn event is determined to have occurred.

29. The method of claim 19, further comprising:

determining that said patient has remained in an orientation for a period of time that exceeds a predetermined duration; and

transmitting an alert that said patient has remained in the orientation for a period of time that exceeds said predetermined duration.