Systems and methods for dynamically identifying a patient support surface and patient monitoring

• US 9,579,047 B2
• Filed: 03/13/2014
• Issued: 02/28/2017
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Careview Communications Incorporated
• Original Assignee: Careview Communications Incorporated
• Inventors: Clark, Matt, del Carpio, Derek, Chapman, Kenneth
• Primary Examiner(s): Yenke, Brian
• Assistant Examiner(s): DESIR, JEAN WICEL
• Application Number:
  US14/209,726
• Publication Number:
  US 20140267625A1
• Time in Patent Office: 1,083 Days
• Field of Search: 348/143, 348/46, 348/42, 348/77, 348/47, 348/208.14, 348/61, 382/103, 705/2, 705/3
• US Class Current: 1/1
• CPC Class Codes: A61B 2576/00 Medical imaging apparatus involving image processing or analysis A61B1/00009, A61B6/52 and A61B8/52 take precedence; image processing per se G06T; details of algorithms for analysing medical images G06T7/0012
• 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 5/0077 Devices for viewing the surface of the body, e.g. camera, magnifying lens
• CPC Class Codes: A61B 5/1115 Monitoring leaving of a patient support, e.g. a bed or a wheelchair
• CPC Class Codes: A61B 5/1117 Fall detection
• CPC Class Codes: A61B 5/1128 using image analysis A61B5/1127 takes precedence
• 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 5/746 Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B
• CPC Class Codes: A61B 5/7475 User input or interface means, e.g. keyboard, pointing device, joystick
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/10028 Range image; Depth image; 3D point clouds
• CPC Class Codes: G06T 7/136 involving thresholding
• CPC Class Codes: G06T 7/70 Determining position or orientation of objects or cameras camera calibration G06T7/80
• CPC Class Codes: G06T 7/97 Determining parameters from multiple pictures depth or shape recovery from multiple images G06T7/55; stereo camera calibration G06T7/85

Abstract

Various patient monitoring systems can include a sensor configured to collect three dimensional information. The systems can identify a location of a patient support surface based on the three dimensional information. The systems can set a two dimensional planar threshold based on the patient support surface. The systems can identify a patient location above the patient support surface based on the three dimensional information and compare the patient location to the two dimensional planar threshold. Exceeding the threshold can be indicative of a high risk of a patient fall. An alert can be generated based on the threshold being exceeded. The systems can repeat the identification of the patient support surface location and the setting of the threshold to account for changes in the patient area.

Claims

1. A patient monitoring system for monitoring a patient area, the system comprising:

a sensor configured to output a plurality of frames, the plurality of frames containing three dimensional information of the patient area, wherein the three dimensional information comprises a plurality of pixels;

a user interface; and

control circuitry configured to;

receive the three dimensional information of the plurality of frames;

identify a location of a patient support surface based on the three dimensional information;

separate the plurality of pixels into a first set and a second set based on the pixels of the first set being above the patient support surface and the pixels of the second set not being above the patient support surface;

set at least one threshold, each of the at least one threshold comprising a two dimensional plane, each of the at least one threshold set at a respective location based on the location of the patient support surface;

identify one or more patient locations based on the three dimensional information;

compare the one or more patient locations to the at least one threshold; and

generate an output with the user interface based on the one or more patient locations traversing the at least one threshold.

2. The patient monitoring system of claim 1, wherein the control circuitry is configured to repeat the identifying the location of the patient support surface and the setting of the at least one threshold steps to dynamically adjust the respective location of the at least one threshold to account for changes in the location of the patient support surface.

3. The patient monitoring system of claim 1, wherein the control circuitry is configured to set the two dimensional plane of each at least one threshold to have a length and a width, and the control circuitry is configured to set one or both of the length and the width based on one or more dimensions of the patient support surface.

4. The patient monitoring system of claim 1, wherein the at least one threshold comprises at least one height threshold that is set to be directly above the patient support surface.

5. The patient monitoring system of claim 1, wherein:

the control circuitry is configured to identify a plurality of planes of the patient support surface, the plurality of planes are contiguous and non-coplanar;

the at least one threshold comprises a plurality of height thresholds; and

the control circuitry is configured to set each of the plurality of height thresholds to correspond to a respective one of plurality of planes such that each of the plurality of thresholds is respectively set directly above the respective one the plurality of planes.

6. The patient monitoring system of claim 1, wherein the at least one threshold comprises at least one lower threshold, each lower threshold set to correspond to a respective area below and laterally offset from the location of the patient support surface.

7. The patient monitoring system of claim 6, wherein the at least one lower threshold comprises a pair of lower thresholds, and the control circuitry is configured to set the pair of lower thresholds on opposite sides of the patient support surface.

8. The patient monitoring system of claim 1, wherein the at least one threshold comprises at least one vertical threshold, each two dimensional plane of each of the at least one vertical threshold extending upward from the patient support surface.

9. The patient monitoring system of claim 1, wherein the at least one threshold comprises at least two of:

(a) a height threshold that is set directly above the patient support surface;

(b) at least one lower threshold that is set to correspond to an area below and laterally offset from the location of the patient support surface; and

(c) at least one vertical threshold, each vertical threshold corresponding to a respective vertical plane extending upward from the patient support surface.

10. The patient monitoring system of claim 1, wherein the control circuitry is configured to identify the one or more patient locations based on the first set while ignoring the second set.

11. The patient monitoring system of claim 1, wherein the control circuitry is configured to identify one or both of the patient support surface and the one or more patient locations based on a buffer comprising the three dimensional information aggregated from a predetermined number of frames, wherein the identification of one or both of the patient support surface and the one or more patient locations is updated based on the reception of each frame of the plurality of frames.

12. The patient monitoring system of claim 1, wherein the output comprises an alert indicative of a heightened risk of the patient falling.

13. The patient monitoring system of claim 1, wherein the control circuitry is configured to identify the patient support surface by identifying an object from the three dimensional information that corresponds with one or more template characteristics.

14. The patient monitoring system of claim 1, further comprising at least one light emitter.

15. The patient monitoring system of claim 14, wherein the sensor receives light emitted from the at least one light emitter and converts the light into electronic signals.

16. A method for processing a chronological series of frames containing three dimensional information generated by a camera to monitor a patient in a patient area by performing the following steps, each step performed at least in part by a computing system:

receiving the three dimensional information of the plurality of frames, wherein the three dimensional information comprises a plurality of pixels;

identifying a location of a patient support surface based on the three dimensional information;

separating the plurality of pixels into a first set and a second set based on the pixels of the first set being directly above the patient support surface and the pixels of the second set not being directly above the patient support surface;

setting at least one threshold, each of the at least one threshold comprising a two dimensional plane, each of the at least one threshold set at a respective location based on the location of the patient support surface;

identifying one or more patient locations based on the three dimensional information;

comparing the one or more patient locations to the at least one threshold; and

generating an output with the user interface based on the one or more patient locations traversing the at least one threshold.

17. The method of claim 16, further comprising repeating the identifying the location of the patient support surface and the setting of the at least one threshold steps to dynamically adjust the respective location of the at least one threshold to account for changes in the location of the patient support surface.

18. The method of claim 16, wherein the two dimensional plane of each at least one threshold is set to have a length and a width, and one or both of the length and the width are set based on one or more dimensions of the patient support surface.

19. The method of claim 16, wherein the at least one threshold comprises a height threshold that is set directly above the patient support surface.

20. The method of claim 19, wherein:

identifying the location of the patient support surface comprises identifying a plurality of planes of the patient support surface, the plurality of planes contiguous and non-coplanar;

the at least one threshold comprises a plurality of height thresholds; and

each of the plurality of height thresholds is set to correspond to a respective one of plurality of planes such that each of the plurality of thresholds is respectively set directly above the respective one of the plurality of planes.

21. The method of claim 16, wherein the at least one threshold comprises a lower threshold that is set to correspond an area below and laterally offset from the location of the patient support surface.

22. The method of claim 21, wherein the at least one lower threshold comprises a pair of lower thresholds, and the pair of lower thresholds are located on opposite sides of the patient support surface.

23. The method of claim 16, wherein the at least one threshold comprises at least one vertical threshold, each two dimensional plane of each of the at least one vertical threshold extending upward from the patient support surface.

24. The method of claim 16, wherein the at least one threshold comprises at least two of:

(a) a height threshold that is set directly above the patient support surface;

(b) at least one lower threshold that is set to correspond to an area below and laterally offset from the location of the patient support surface; and

(c) at least one vertical threshold, each vertical threshold corresponding to a respective vertical plane extending upward from the patient support surface.

25. The method of claim 16, wherein the identification of the one or more patient locations is based on the first set while the second set is ignored.

26. The method of claim 17, further comprising aggregating the three dimensional information from a predetermined number of frames in a buffer, wherein identifying the location of one or both of the patient support surface and the one or more patient locations comprises determining a nominal location of the patient support surface or the one or more patient locations based on the aggregation of the three dimensional information, and wherein the identification of one or both of the patient support surface and the one or more patient locations is updated based on the reception of each frame of the plurality of frames.

27. The method of claim 17, wherein the output comprises an alert indicative of a heightened risk of the patient falling.

28. The method of claim 16, wherein the camera further comprises at least one light emitter.

29. The method of claim 28, further comprising:

receiving light emitted from the at least one light emitter; and

converting the light into electronic signals.

30. A patient monitoring system for monitoring a patient area, the system comprising:

means for generating a plurality of frames, the plurality of frames containing three dimensional information of the patient area, wherein the three dimensional information comprises a plurality of pixels;

means for identifying a location of a patient support surface based on the three dimensional information;

means for separating the plurality of pixels into a first set and a second set based on the pixels of the first set being directly above the patient support surface and the pixels of the second set not being directly above the patient support surface;

means for setting at least one threshold, each of the at least one threshold comprising a two dimensional plane, each of the at least one threshold set at a respective location based on the location of the patient support surface;

means for identifying one or more patient locations based on the three dimensional information;

means for comparing the one or more patient locations to the at least one threshold; and

means for generating an output based on the one or more patient locations traversing the at least one threshold.