Systems and methods for monitoring and/or managing patient orientation using a dynamically adjusted relief period

• US 10,020,075 B2
• Filed: 03/24/2010
• Issued: 07/10/2018
• Est. Priority Date: 03/24/2009
• Status: Active Grant

• Current Assignee: Leaf Healthcare, Inc. (Smith & Nephew PLC), Wound Sentry LLC
• Original Assignee: Leaf Healthcare, Inc. (Smith & Nephew PLC)
• Inventors: Perlman, David, Himle, Joseph
• Primary Examiner(s): Towa, Rene
• Assistant Examiner(s): Nguyen, H. Q.
• Application Number:
  US12/730,663
• Publication Number:
  US 20100298742A1
• Time in Patent Office: 3,030 Days
• Field of Search: 600587, 600595, 702149, 702150
• CPC Class Codes: A61B 2560/0443 Modular apparatus
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 2562/18 Shielding or protection of sensors from environmental influences, e.g. protection from mechanical damage
• CPC Class Codes: A61B 5/1116 Determining posture transitions
• 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 5/7275 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 5/742 using visual displays A61B5/339 takes precedence
• 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: G16H 40/63 for local operation
• CPC Class Codes: G16Z 99/00 Subject matter not provided for in other main groups of this subclass

Abstract

A monitoring system and method tracks a patient'"'"'s position over time and ensures that proper turning or other manipulation is done within the time prescribed. Preferably, the techniques herein continuously monitor patient position and alert medical or other personnel of the need for turning or other patient manipulation. The system may be implemented within a medical or other care facility, or within a patient'"'"'s home.

Claims

1. A system for managing patient orientation according to a patient turn protocol, the system comprising:

a sensor configured to be physically wearable by a patient and outputting sensor-based orientation information representative of changes in the patient'"'"'s body orientation with respect to a support surface, during a series of (a) pressure-on periods in which the patient is in a pressure-on orientation in which a particular area of the patient'"'"'s body experiences pressure from the support surface, wherein the series of pressure-on periods have varying durations, and (b) relief periods in which the patient is in a relief orientation other than the pressure-on orientation;

a processor and memory in communication with the sensor and configured to;

receive and store the sensor-based orientation information together with temporal information associated with the sensor-based orientation information;

generate commands or alerts for changing the orientation of the patient according to the patient turn protocol based on information including;

(a) the stored sensor-based orientation information and associated temporal information;

(b) a maximum time-on threshold that indicates a maximum time the patient is permitted to remain in the pressure-on orientation during each respective pressure-on period before changing to the relief orientation to help avoid development of a pressure ulcer; and

(c) a minimum time-off threshold that indicates a minimum time the patient is required to remain in the relief orientation during each respective relief period before returning to the pressure-on orientation; and

for at least some of the relief periods, dynamically set the minimum time-off threshold for each respective relief period by;

measuring a duration of a pressure-on period immediately preceding the respective relief period based on the sensor-based orientation information and associated temporal information; and

calculating a minimum time-off threshold for the respective relief period based on a proportional relationship between the minimum time-off threshold and a respective pressure-on duration including the measured duration of the pressure-on period immediately preceding the respective relief period;

wherein according to the proportional relationship, increasing the respective pressure-on duration results in a proportional increase in the calculated minimum time-off threshold, such that numerically different minimum time-off thresholds are calculated for different relief periods, depending on the respective pressure-on durations preceding the different relief periods; and

a device configured to output the commands or alerts for changing the orientation of the patient according to the patient turn protocol.

2. The system of claim 1, wherein the monitor comprises a bedside receiving station.

3. The system of claim 2, wherein the bedside receiving station is an intelligent mobile device.

4. The system of claim 1, wherein the monitor comprises an attendant receiving station.

5. The system of claim 1, wherein the sensor is in communication with the monitor over a wireless link.

6. The system of claim 1, wherein the sensor is self-powered.

7. The system of claim 1, wherein the orientation information includes at least one of:

a current orientation, a change in the patient'"'"'s orientation, a magnitude of a change in orientation, a frequency of a change in the patient'"'"'s orientation, or one or more allowed or disallowed positions.

8. The system of claim 1, wherein the temporal information includes at least one of:

a start time, a time since a last turn, a time until a next turn, or a current or elapsed time.

9. The system of claim 1, wherein the notification output by the device is an alarm.

10. The system of claim 1, wherein the physically wearable sensor is adhesively coupled to the patient.

11. The system of claim 1, wherein the sensor, the processor and memory, and the device to output the notification are provided in a wearable sensor device.

12. The system of claim 1, wherein the processor and memory and the device to output the notification are distinct from the wearable sensor.

13. The system of claim 1, wherein the processor is further configured to:

identify a non-compliance with the patient turn protocol based on the sensor-based orientation information and at least one of the maximum time-on threshold or the minimum time-off threshold; and

generate a command or alert in response to identifying the non-compliance with the patient turn protocol.

14. A system for monitoring a patient, the system comprising:

a patient-worn sensor device including one or more sensors configured to generate sensor data associated with a physical orientation of the patient during a period in which the patient moves or is moved between different orientations over time, including a series of instances of the patient in (a) a pressure-on orientation in which a particular area of the patient'"'"'s body experiences pressure from a support surface and (b) a relief orientation other than the pressure-on orientation, wherein different instances of the patient in the pressure-on orientation have different durations;

wherein the patient-worn sensor device is configured to be secured to the patient or an article worn by the patient;

a processor configured to;

receive sensor data from the one or more sensors of the patient-worn sensor device;

based on the received sensor data;

determine that the patient is in the pressure-on orientation during a pressure-on time period;

determine a change in the patient'"'"'s orientation from the pressure-on orientation to the relief orientation; and

measure a duration of the pressure-on time period; and

in response to determining the change in the patient'"'"'s orientation from the pressure-on orientation to the relief orientation;

dynamically calculate a minimum time-off duration based on a proportional relationship between the minimum time-off duration and a variable pressure-on duration including the measured duration of the pressure-on time period, wherein the minimum time-off duration indicates a minimum duration for remaining in the relief orientation before permitting a return to the pressure-on orientation, such that the calculated minimum time-off duration is variable in proportion to the variable pressure-on duration;

determine a change in the patient'"'"'s orientation from the relief orientation back to the pressure-on orientation based on the received sensor data; and

generate an alert in response to a determination that the determined change from the relief orientation back to the pressure-on orientation occurs prior to expiration of the minimum time-off duration.

15. The system of claim 14, wherein the processor is provided in the patient-worn sensor device.

16. The system of claim 14, wherein the processor is distinct from the patient-worn sensor device.

17. A method for monitoring a patient, comprising:

collecting, by a patient-worn sensor device including one or more sensors, sensor-based patient orientation information indicating a physical orientation of the patient over time, wherein the patient-worn sensor device is worn by or otherwise affixed to the patient;

wherein the patient moves or is moved between different orientations over time, including (a) a series of pressure-on periods in a pressure-on orientation in which a particular area of the patient'"'"'s body experiences pressure from a support surface and (b) a series of relief periods in a relief orientation other than the pressure-on orientation, wherein the series of pressure-on periods have varying durations;

receiving, at a processor, sensor-based patient orientation information collected by the patient-worn sensor device;

determining, by the processor, changes in the physical orientation of the patient over time;

for each of the series of pressure-on periods in which the patient is in the pressure-on orientation;

measuring a duration of the respective pressure-on period based on sensor-based patient orientation information;

comparing, by the processor, the measured duration of the respective pressure-on period to a maximum pressure-on period threshold; and

generating a notification in response to a determination that the pressure-on period duration exceeds the maximum pressure-on period threshold;

for each of a series of relief periods in which the patient is in the relief orientation, comparing, by the processor, a duration of that relief period to a minimum relief period threshold dynamically determined for that relief period, and generating a notification in response to a determination that the relief period duration is less than the minimum relief period threshold dynamically determined for that relief period; and

for at least some relief periods, dynamically calculating, by the processor, the minimum relief period threshold for each respective relief period by;

calculating a minimum time-off threshold value for the respective relief period using a proportional relationship with a respective variable pressure-on duration including the measured duration of the pressure-on period immediately preceding the respective relief period;

such that the calculated minimum time-off threshold value for each relief period varies according to the proportional relationship with the respective variable pressure-on duration corresponding to that relief period, wherein according to the proportional relationship, increasing the pressure-on duration preceding a respective relief period results in a proportional increase in the calculated minimum time-off threshold value for the respective relief period.

18. A method for monitoring a patient, comprising:

collecting, by a patient-worn sensor device including one or more sensors, sensor-based patient orientation information indicating a physical orientation of the patient over time, wherein the patient-worn sensor device is worn by or otherwise affixed to the patient;

wherein the patient changes or is changed between different orientations over time, to define (a) a series of pressure-on periods in which the patient is in a pressure-on orientation in which a particular area of the patient'"'"'s body experiences pressure from a support surface, wherein at least some of the series of pressure-on periods have different durations, and (b) a series of relief periods in which the patient is in a relief orientation other than the pressure-on orientation;

receiving, at a processor, sensor-based patient orientation information collected by the patient-worn sensor device;

monitoring, by the processor, changes in the patient'"'"'s orientation over time based on the received sensor-based patient orientation information;

for at least some relief periods, the processor dynamically calculating a minimum relief period threshold for each respective relief period based on a proportional relationship between the minimum relief period threshold and a pressure-on duration including a measured duration of a respective pressure-on period immediately preceding that respective relief period, wherein according to the proportional relationship, increasing the pressure-on duration preceding a respective relief period results in a proportional increase in the calculated minimum time-off threshold for the respective relief period, such that numerically different minimum relief period thresholds are calculated for different relief periods, depending on the respective pressure-on durations preceding the different relief periods;

measuring a duration of each respective relief period based on sensor-based patient orientation information collected by the patient-worn sensor device; and

for each respective relief period, the processor generating a notification in response to detecting, based on sensor-based patient orientation information collected by the patient-worn sensor device, a change in the patient'"'"'s orientation from the relief orientation back to the pressure-on orientation before the minimum relief period threshold determined for that respective relief period.

19. The method of claim 18, wherein dynamically calculating the minimum relief period threshold comprises:

determining a first change in the patient'"'"'s physical orientation from a first period in the pressure-on orientation to a first period in the relief orientation;

dynamically determining a first minimum relief period threshold for the first period in the relief orientation based on a measured duration of the first period in the pressure-on orientation;

after expiration of the first minimum relief period, determining a second change in the physical orientation of the patient from the first period in the relief orientation to a second period in the pressure-on orientation;

determining a third change in the physical orientation of the patient from the second period in the pressure-on orientation to a second period in the relief orientation; and

dynamically determining a second minimum relief period threshold for the second period in the relief orientation based on a measured duration of the second period in the pressure-on orientation, wherein the second minimum relief period threshold is numerically different than the first minimum relief period threshold.