Pressure control apparatus

• US 10,058,644 B2
• Filed: 12/17/2015
• Issued: 08/28/2018
• Est. Priority Date: 09/20/2010
• Status: Active Grant

• Current Assignee: Smith & Nephew PLC
• Original Assignee: Smith & Nephew PLC
• Inventors: Nicolini, Derek
• Primary Examiner(s): KLEIN, BENJAMIN JACOB
• Application Number:
  US14/972,734
• Publication Number:
  US 20160166741A1
• Time in Patent Office: 985 Days
• CPC Class Codes: A61F 13/05 specially adapted for use with sub-pressure or over-pressure therapy, wound drainage or wound irrigation, e.g. for use with negative-pressure wound therapy [NPWT]
• CPC Class Codes: A61F 2013/00174 possibility of applying pressure
• CPC Class Codes: A61M 1/73 comprising sensors or indicators for physical values
• CPC Class Codes: A61M 1/732 Visual indicating means for vacuum pressure
• CPC Class Codes: A61M 1/74 Suction control underwater drainage A61M1/61
• CPC Class Codes: A61M 1/743 by changing the cross-section of the line, e.g. flow regulating valves A61M1/7413 takes precedence
• CPC Class Codes: A61M 1/75 Intermittent or pulsating suction A61M1/63, A61M1/772 take precedence
• CPC Class Codes: A61M 1/80 Suction pumps A61M1/64, A61M1/71, A61M60/00 take precedence
• CPC Class Codes: A61M 1/90 Negative pressure wound therapy devices, i.e. devices for applying suction to a wound to promote healing, e.g. including a vacuum dressing
• CPC Class Codes: A61M 1/96 Suction control thereof
• CPC Class Codes: A61M 1/966 having a pressure sensor on or near the dressing
• CPC Class Codes: A61M 1/985 the dressing itself forming the collection container
• CPC Class Codes: A61M 2205/15 Detection of leaks
• CPC Class Codes: A61M 2205/18 with alarm
• CPC Class Codes: A61M 2205/3344 Measuring or controlling pressure at the body treatment site
• CPC Class Codes: A61M 2205/42 Reducing noise
• CPC Class Codes: A61M 2205/8212 with means or measures taken for minimising energy consumption
• CPC Class Codes: A61M 39/22 Valves or arrangement of valves A61M39/02, A61M39/0247, A61M39/16 take precedence; regulating valves in infusion systems A61M5/16881; in devices worn by the patient for the reception of urine, faeces, catamenial or other discharge, or in colostomy devices A61F5/4405
• CPC Class Codes: A61M 5/16831 Monitoring, detecting, signalling or eliminating infusion flow anomalies low-level float-valves causing cut-off A61M5/40; indicating or recording presence, absence or direction of flow in general G01P13/0066
• CPC Class Codes: A61M 5/48 having means for varying, regulating, indicating or limiting injection pressure A61M5/142 takes precedence ; monitoring pressure in infusion systems A61M5/16854

Abstract

Methods and apparatuses are disclosed for applying negative pressure to a wound site. In some embodiments, the apparatus comprises a source of negative pressure, a processing element, and a memory comprising instructions configured to, when executed on the processing element, cause the apparatus to attempt to generate, via the source of negative pressure, a desired negative pressure at the wound site. If the desired negative pressure has not been generated after a first predetermined period of time, the instructions cause the apparatus to: deactivate the source of negative pressure for a second predetermined period of time, and subsequently attempt to generate the desired negative pressure at the wound site.

Claims

1. A negative pressure wound therapy apparatus comprising:

a negative pressure source configured to be in fluid communication, via a fluid flow path, with a wound dressing positioned over a wound; and

a controller configured to;

in response to the negative pressure source attempting to generate a level of negative pressure under the wound dressing and failing to generate the level of negative pressure under the wound dressing;

deactivate operation of the negative pressure source, and

subsequent to deactivating operation of the negative pressure source, operate the negative pressure source for a number of retry cycles to attempt to generate the level of negative pressure under the wound dressing, the number of retry cycles being one or more cycles; and

pause operation of the negative pressure source in response to determining that the level of negative pressure under the wound dressing has not been generated as a result of operating the negative pressure source for the number of retry cycles.

2. The apparatus of claim 1, wherein the negative pressure source comprises a pump, and the controller is configured to deactivate operation of the negative pressure source by turning off the pump.

3. The apparatus of claim 1, wherein the negative pressure source comprises a valve positioned in the fluid flow path, and the controller is configured to deactivate operation of the negative pressure source by closing the valve.

4. The apparatus of claim 1, wherein the controller is further configured to indicate presence of a leak in response to determining that the level of negative pressure under the wound dressing has not been generated as the result of operating the negative pressure source for the number of retry cycles.

5. The apparatus of claim 1, wherein the controller is further configured to:

receive a pressure measurement from a sensor positioned in the fluid flow path; and

determine the level of negative pressure under the wound dressing based at least on the pressure measurement.

6. The apparatus of claim 1, wherein the controller is further configured to:

monitor a duty cycle of the negative pressure source; and

terminate a first retry cycle of operating the negative pressure source in response to determining that the duty cycle satisfies a duty cycle threshold for a period of time without the level of negative pressure under the wound dressing being generated.

7. The apparatus of claim 1, wherein the number of retry cycles is one cycle.

8. The apparatus of claim 1, wherein the number of retry cycles is at least two cycles.

9. A method of operating a negative pressure wound therapy apparatus, the method comprising:

attempting to generate a level of negative pressure under a wound dressing with the negative pressure source and failing to generate the level of negative pressure under the wound dressing;

in response to attempting to generate the level of negative pressure under the wound dressing with the negative pressure source and failing to generate the level of negative pressure under the wound dressing;

deactivating operation of the negative pressure source, and

subsequent to deactivating operation of the negative pressure source, attempting to generate the level of negative pressure under the wound dressing with the negative pressure source for a number of retry cycles, the number of retry cycles being one or more cycles;

determining that the level of negative pressure under the wound dressing has not been generated as a result of attempting to generate the level of negative pressure under the wound dressing for the number of retry cycles; and

pausing operation of the negative pressure source in response to determining that the level of negative pressure under the wound dressing has not been generated as the result of attempting to generate the level of negative pressure under the wound dressing for the number of retry cycles,

wherein the method is performed by a controller of the negative pressure wound therapy apparatus.

10. The method of claim 9, further comprising indicating presence of a leak in response to determining that the level of negative pressure under the wound dressing has not been generated as the result of attempting to generate the level of negative pressure under the wound dressing for the number of retry cycles.

11. The method of claim 9, further comprising:

monitoring a duty cycle of the negative pressure source; and

in response to determining that the duty cycle satisfies a duty cycle threshold for a period of time without the level of negative pressure under the wound dressing being generated, terminating a first retry cycle of attempting to generate the level of negative pressure under the wound dressing.

12. The method of claim 9, wherein the number of retry cycles is at least two cycles.

13. The method of claim 9, further comprising:

receiving a pressure measurement from a sensor positioned in the fluid flow path; and

determining the level of negative pressure under the wound dressing based at least on the pressure measurement.

14. The method of claim 9, wherein the number of retry cycles is one cycle.

15. A negative pressure wound therapy apparatus comprising:

a negative pressure source configured to be in fluid communication, via a fluid flow path, with a wound dressing positioned over a wound; and

a controller configured to;

in response to operating the negative pressure source to attempt to generate a level of negative pressure under the wound dressing and failing to generate the level of negative pressure under the wound dressing;

deactivate operation of the negative pressure source,

subsequent to deactivating operation of the negative pressure source, operate the negative pressure source for a number of retry cycles to attempt to generate the level of negative pressure under the wound dressing, the number of retry cycles being one or more cycles, and

delay indicating presence of a leak in the fluid flow path while operating the negative pressure source for the number of retry cycles; and

indicate presence of the leak in the fluid flow path in response to determining that the level of negative pressure under the wound dressing has not been generated as a result of operating the negative pressure source for the number of retry cycles.

16. The apparatus of claim 15, wherein the controller is further configured to:

receive a pressure measurement from a sensor positioned in the fluid flow path; and

determine the level of negative pressure under the wound dressing based at least on the pressure measurement.

17. The apparatus of claim 15, wherein the controller is further configured to:

monitor a duty cycle of the negative pressure source; and

terminate a first retry cycle of operating the negative pressure source in response to determining that the duty cycle satisfies a duty cycle threshold for a period of time without the level of negative pressure under the wound dressing being generated.

18. The apparatus of claim 15, wherein the number of retry cycles is at least two cycles.

19. The apparatus of claim 15, wherein the negative pressure source comprises a pump, and the controller is configured to deactivate operation of the negative pressure source by turning off the pump.

20. The apparatus of claim 15, wherein the negative pressure source comprises a valve positioned in the fluid flow path, and the controller is configured to deactivate operation of the negative pressure source by closing the valve.

21. The apparatus of claim 15, wherein the number of retry cycles is one cycle.