Lack of patient movement monitor and method

• US 7,557,718 B2
• Filed: 05/02/2005
• Issued: 07/07/2009
• Est. Priority Date: 04/30/2004
• Status: Active Grant

• Current Assignee: Hill-Rom Services Incorporated (Baxter International Inc.)
• Original Assignee: Hill-Rom Services Incorporated (Baxter International Inc.)
• Inventors: Lokhorst, David, Skinner, Andrew F., Sleva, Michael Z., Mueller, Jonathan H., Stacy, Richard B., Petrosenko, Robert, Bobey, John A., Yermaneni, Mayur, Jacques, William L. II, Janoff, Karen
• Primary Examiner(s): Bugg; George A
• Assistant Examiner(s): LAI, ANNE VIET NGA
• Application Number:
  US11/119,635
• Publication Number:
  US 20050273940A1
• Time in Patent Office: 1,527 Days
• Field of Search: 340/573.1, 340665-667, 340/573.4, 561/5, 565/4, 571/3, 572/2, 600/534, 600/595, 177/45, 177/144, 177/199
• US Class Current: 340/573.1
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 2562/046 in a matrix array
• CPC Class Codes: A61B 5/1126 using a particular sensing technique
• CPC Class Codes: A61B 5/6887 mounted on external non-worn devices, e.g. non-medical devices
• CPC Class Codes: A61B 5/6892 Mats
• CPC Class Codes: A61B 5/743 Displaying an image simultaneously with additional graphical information, e.g. symbols, charts, function plots
• CPC Class Codes: A61G 2203/32 for force
• CPC Class Codes: A61G 2203/34 for pressure
• CPC Class Codes: A61G 2203/42 for inclination
• CPC Class Codes: A61G 7/008 tiltable around longitudinal axis, e.g. for rolling
• CPC Class Codes: A61G 7/05769 with inflatable chambers
• CPC Class Codes: G16H 40/63 for local operation

Abstract

A lack of patient movement monitor and method. The monitor and method patient support includes a plurality of sensors located beneath a patient support to determine movement of a patient. An alarm is activated when patient movement over time is determined to be lacking.

Claims

1. In a pressure adjustable support, including a bladder assembly having a plurality of bladders to support a patient, a plurality of sensors, each of the plurality of sensors subtending at least one of the bladders to sense a force transmitted through the bladders, a method comprising the steps of:

setting a time period for determining an activity level;

setting a threshold level with respect to the sensed force;

sampling the forces sensed by each of the plurality of sensors transmitted through the bladders;

filtering the sampled forces to determine a high frequency component;

determining which of the filtered sampled forces exceed the set threshold level;

determining the number of filtered sampled forces determined to cross the threshold level; and

generating a signal as a function of the set time period, the set threshold level, and the sampled forces.

2. The method of claim 1, the step of sampling the forces sensed by each of the plurality of sensors including sampling over a predetermined period of time the forces sensed by each of the plurality of sensors.

3. The method of claim 1, comprising the step of determining the amount of time the filtered sampled forces exceed the threshold level during the predetermined period of time.

4. The method of claim 3, comprising the step of determining a sum of the total amount of the filtered sampled forces exceeding the threshold level.

5. The method of claim 4, further comprising the step of determining the maximum filtered sampled force.

6. The method of claim 5, further comprising the step of storing the maximum filtered sampled force.

7. The method of claim 5, further comprising the step of determining a weight for at least one of the number of filtered sampled forces exceeding the threshold level, the amount of time the filtered sampled forces exceed the threshold level during the predetermined period of time, sum of the total amount of the filtered sampled forces exceeding the threshold level, and the maximum filtered sample force.

8. The method of claim 1, wherein the bladder assembly includes a plurality of vertically oriented bladders.

9. The method of claim 8, wherein the bladder assembly includes an air chamber shared by each of the plurality of vertically oriented bladders.

10. The method of claim 1, wherein each of the plurality of sensors comprise a light responsive device disposed in a compressible medium.

11. The method of claim 10, the step of sampling the forces sensed by each of the plurality of sensors including sampling the forces in a predetermined order.

12. The method of claim 11, the step of sampling the forces in a predetermined order wherein the predetermined order includes sampling the forces consecutively from non-adjacent sensors.

13. A motion monitor device for monitoring the motion of a patient lying on a hospital bed, including a mattress comprising;

a plurality of bladders;

a plurality of sensors subtending at least one of the bladders;

a motion monitor operably coupled to the sensors and configured to sample forces sensed by each of the sensors over a time period, set a threshold level with respect to the sensed forces, filter the sampled forces to determine a high frequency component, determine which of the filtered sampled forces exceed the threshold level, and determine a number of the filtered sampled forces that exceed the threshold force level; and

a user interface device, operatively coupled to the motion monitor, the user interface device including a screen to display motion information and an input device to input motion parameters to determine patient motion.

14. The motion monitor device of claim 13, wherein the input devices includes a time period selector to select a time period over which the motion of the patient is determined.

15. The motion monitor device of claim 14, wherein the input device includes a threshold selector to select a threshold for movement above which the patient is determined to be mobile.

16. The motion monitor device of claim 15, wherein the input device includes a history selector to select a history of the monitored motion.

17. The motion monitor device of claim 15, wherein the user interface device includes an alarm to indicate when motion of a patient over time falls below the selected threshold level.

18. The motion monitor device of claim 13, further including a processor operatively coupled to the user interface device and to the plurality of sensors, the processor to received the motion parameters from the input device and to transmit information to the screen.

19. The motion monitor device of claim 18, wherein the processor generates a mobile signal responsive to movement of a patient sensed by the plurality of sensors for display on the screen.

20. The motion monitor device of claim 19, wherein the processor generates an immobile signal responsive to movement of a patient sensed by the plurality of sensors for display on the screen.

21. The motion monitor device of claim 20, wherein the processor generates a bed empty signal responsive to an empty bed sensed by the plurality of sensors for display on the screen.