Force optimization surface apparatus and method

• US 6,721,980 B1
• Filed: 10/16/2000
• Issued: 04/20/2004
• Est. Priority Date: 10/28/1998
• Status: Expired due to Term

• Current Assignee: Hill-Rom Incorporated (Baxter International Inc.)
• Original Assignee: Hill-Rom Services Incorporated (Baxter International Inc.)
• Inventors: Repik, Marla, Bries, Nick, Price, James H., Thomas, James Milton Cherry, Caldwell, Karl, Mensching, Kerry J., Stolpmann, James R., Taylor, Geoffrey Locke
• Primary Examiner(s): Grosz, Alexander
• Application Number:
  US09/673,437
• Time in Patent Office: 1,282 Days
• Field of Search: 571/3, 571/0, 571/4, 571/5
• US Class Current: 5/713
• 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 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/1036 Measuring load distribution, e.g. podologic studies
• CPC Class Codes: A61B 5/11 Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb for measuring pulse A61B5/02 ;A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721
• CPC Class Codes: A61B 5/1126 using a particular sensing technique
• CPC Class Codes: A61B 5/113 occurring during breathing
• CPC Class Codes: A61B 5/447 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 5/4818 Sleep apnoea
• CPC Class Codes: A61B 5/6892 Mats
• CPC Class Codes: A61G 2203/32 for force
• CPC Class Codes: A61G 2203/34 for pressure
• CPC Class Codes: A61G 2203/44 for weight
• CPC Class Codes: A61G 2203/46 for temperature
• CPC Class Codes: A61G 2203/74 for anti-shear when adjusting furniture
• CPC Class Codes: A61G 7/0527 Weighing devices
• CPC Class Codes: A61G 7/05715 with modular blocks, or inserts, with layers of different material
• CPC Class Codes: A61G 7/05769 with inflatable chambers
• CPC Class Codes: G01G 19/445 in a horizontal position
• CPC Class Codes: G01G 23/3728 : with wireless means
• CPC Class Codes: G01G 5/006 : with pneumatic means

Abstract

A force optimization apparatus is provided including a patient support surface and an interface pressure sensor.

Claims

1. A method of minimizing a force between a modifiable support surface and a patient located thereon, the method comprising the steps of:

establishing an initial recorded force between the patient and the support surface;

performing a first procedure including modifying the support surface in a first manner for a predetermined time increment, measuring the current force between the patient and the surface, comparing the current force to the recorded force, and replacing the recorded force with the current force,

repeating the first procedure so long as the current force is less than the recorded force,

then performing a second procedure including modifying the support surface in a second manner for a predetermined time increment, measuring the current force between the patient and the support surface, comparing the current force to the recorded force, and replacing the recorded force with the current force, and

repeating the second procedure so long as the current force is less than the recorded force.

2. The method of claim 1, and further comprising the step of again performing the first procedure after the step of repeating the second procedure.

3. The method of claim 2, wherein the establishing step further comprises the step of establishing a maximum limit which cannot be exceeded during the first procedure and wherein the repeating the first procedure step continues so long as the current force is less than the recorded force and the maximum limit is not exceeded.

4. The method of claim 1, wherein the modifiable surface includes an inflatable chamber having a pressure and wherein the modifying step of the first procedure includes supplying air to the chamber.

5. The method of claim 4, wherein the modifying step of the second procedure includes venting air from the chamber.

6. The method of claim 5, wherein the establishing step includes the step of establishing a minimum pressure below which the chamber is not permitted to remain and wherein the second procedure includes the step of comparing the pressure in the chamber following each venting air step with the minimum pressure and continuing the second procedure only so long as the current pressure is above the minimum pressure.

7. The method of claim 4, wherein the establishing step includes the step of establishing a maximum pressure above which the chamber is not permitted to remain and the first procedure includes the step of comparing the pressure in the chamber following each supplying air step with the maximum pressure and continuing the first procedure only so long as the current pressure is below the maximum pressure.

8. A method of controlling the pressure in an inflatable surface containing a plurality of independently inflatable chambers to minimize a force exerted by each inflatable chamber on a patient, the method comprising the steps of:

establishing a minimum pressure for each chamber below which the pressure of the chamber is not permitted to remain, a maximum pressure for each chamber above which the pressure of the chamber is not permitted to remain, an initial set pressure for each chamber between the minimum pressure and the maximum pressure, and an initial recorded force for each chamber,

inflating each chamber until the pressure in each chamber is at substantially the initial set pressure for that chamber,

performing a supply procedure including the steps of selecting a chamber which is not in a no-pump mode, supplying air to the selected chamber in an increment, measuring the current force on the selected chamber, comparing the current force on the selected chamber to the recorded force for the selected chamber, placing the selected chamber in a no-pump mode if the current force is not less than the recorded force for the selected chamber, replacing the recorded force for the selected chamber with the current force for the selected chamber, repeating the selecting, supplying, measuring, comparing, placing, and replacing steps of the supply procedure until all zones are not in a no-pump mode,

then performing a vent procedure including the steps of selecting a chamber which is not in a no-vent mode, venting air from the selected chamber in an increment, measuring the current force on the selected chamber, comparing the current force on the selected chamber to the recorded force for the selected chamber, placing the selected chamber in a no-pump mode if the current force is not less than the recorded force for the selected chamber, replacing the recorded force for the selected chamber with the current force for the selected chamber, repeating the selecting, supplying, measuring, comparing, placing, and replacing steps of the vent procedure until all zones are in a no-vent mode,

then repeating the supply procedure.

9. A force optimization apparatus for minimizing forces between a support surface and a patient, the apparatus comprising:

a patient support surface including a plurality of independently controllable pressure sections and a force sensing material located in an upper support surface layer; and

a controller configured to adjust pressure in the support surface pressure sections based on an interface force for each section sensed by the force sensing material.

10. The apparatus of claim 9, wherein the controller is configured to analyze interface forces on multiple sections of the patient support surface and control pressure within the sections to reduce the interface force for each section.

11. The apparatus of claim 10, wherein the controller is configured to reduce interface forces for each section without regard to support surface orientation.

12. The apparatus of claim 9, including an integrated weight sensor.

13. The apparatus of claim 12, wherein the integrated weight sensor includes and air bladder.

14. The apparatus of claim 12, wherein the weight sensor is an integrated pressure sensing material incorporated into an upper support surface layer.

15. The apparatus of claim 12, wherein the controller is configured to monitor, record, or display a patient'"'"'s weight or changes in weight from a preset value based on weight sensor information provided from the weight sensor integrated into the patient support surface.

16. The apparatus of claim 9, wherein the controller is configured to monitor, record, or display a patient'"'"'s vital signs such as heart rate, reparations, and skin temperature based on information from one or more sensors integrated into a support surface.

17. The apparatus of claim 9, wherein the controller is configured to monitor apnea conditions based on information from a sensor integrated into the patient support surface.

18. The apparatus of claim 9, wherein the controller is configured to signal an alert based on vital sign information derived from a sensor integrated into the support surface.

19. The apparatus of claim 9, wherein the controller is configured to monitor information from a sensor integrated into the patient support surface and to vibrate the patient support upon detection of an apnea condition based on the monitored information.

20. A support surface apparatus comprising:

at least one air bladder for supporting a person;

a force sensor located on the at least one air bladder, the force sensor being configured to measure a force between the person and the at least one air bladder;

an air supply coupled to the at least one air bladder; and

a controller coupled to the force sensor, the controller being configured to adjust air pressure within the at least one air bladder based on the force detected by the force sensor to minimize the force between the person and the at least one bladder.

21. The apparatus of claim 20, wherein the controller is configured to increase the air pressure in the at least one air bladder during a time period in which the force detected by the force sensor is decreasing.

22. The apparatus of claim 21, wherein the controller stops increasing the air pressure in the at least one air bladder when the force detected by the force sensor increases, the controller being configured to decrease the air pressure in the at least one air bladder for a time period in which the force detected by the force sensor is decreasing.

23. The apparatus of claim 22, wherein the controller is configured to maintain the air pressure within the at least one air bladder between a predetermined maximum pressure and a predetermined minimum pressure.

24. The apparatus of claim 20, wherein a plurality of separate air bladders are provided for supporting different portions of the person, and wherein a separate force sensor is located on each of the plurality of air bladders to measure the force between the person and each air bladder, the controller being configured to adjust air pressure within each of the plurality of air bladders based upon the forces detected by the force sensors to minimize the force between the person and each of the plurality of air bladders.

25. The apparatus of claim 24, wherein the plurality of air bladders form separate support zones spaced along a length dimension of the support surface.

26. The apparatus of claim 25, wherein the plurality of air bladders also form separate zones spaced along a width dimension of the support surface.

27. The apparatus of claim 20, wherein the force sensor is a resistive force sensor.

28. The apparatus of claim 20, wherein the force sensor measures a maximum force on the at least one air bladder.

29. The apparatus of claim 20, wherein the force sensor includes a plurality of capacitive force sensors located on the at least one air bladder.

30. The apparatus of claim 20, wherein the force sensor includes a plurality of pneumatic force sensors located on the at least one air bladder.

31. The apparatus of claim 20, wherein the force sensor includes thermistors which also measure a temperature on the sensor.

32. The apparatus of claim 20, further comprising a weigh bladder located below the at least one air bladder, the weighing bladder being configured to measure a weight of the person on the at least one air bladder.

33. A support surface apparatus comprising:

at least one support member for supporting a person;

a force sensor located on the at least one support member, the force sensor being configured to measure a force between the person and the at least one support member; and

a mechanism configured to adjust a support characteristic of the at least one support member based upon the force detected by the force sensor to minimize the force between the person and the at least one support member.