APPARATUS AND METHOD FOR CONTROLLING THE NEGATIVE PRESSURE IN A WOUND

• US 20120184930A1
• Filed: 09/21/2010
• Published: 07/19/2012
• Est. Priority Date: 09/22/2009
• Status: Active Grant

• Current Assignee: Molnlycke Health Care AB (Mölnlycke Holding AB)
• Original Assignee: Molnlycke Health Care AB (Mölnlycke Holding AB)
• Inventors: Johannison, Ulf
• Granted Patent: US 8,998,863 B2
• Time in Patent Office: Days
• US Class Current: 604/318
• CPC Class Codes: A61M 1/74 Suction control underwater drainage A61M1/61
• CPC Class Codes: A61M 1/784 by filtering, sterilising or disinfecting the exhaust air, e.g. swellable filter valves
• CPC Class Codes: A61M 1/85 with gas or fluid supply means, e.g. for supplying rinsing fluids or anticoagulants for negative pressure wound therapy A61M1/92, A61M1/94; combined with tracheal tubes A61M16/0463; dental instruments with combined rinsing and aspirating A61C17/0208
• CPC Class Codes: A61M 1/882 Draining devices provided with means for releasing antimicrobial or gelation agents in the drained fluid
• CPC Class Codes: A61M 1/915 Constructional details of the pressure distribution manifold
• CPC Class Codes: A61M 1/982 with means for detecting level of collected exudate
• CPC Class Codes: A61M 2205/18 with alarm
• CPC Class Codes: A61M 27/00 Drainage appliance for wounds or the like , i.e. wound drains, implanted drains negative pressure wound therapy devices A61M1/90; implements for holding wound open A61B17/02 ; middle ear drainage A61F11/202

Abstract

An apparatus and method are provided for treating wound with negative pressure. The apparatus includes a wound cover, a first pump for providing said negative pressure at a chosen pressure level to the wound, a canister, a first conduit between the wound cover and the canister, first means for measuring the pressure within the canister, and a second conduit which connects the canister with the first pump. A circulating pump is arranged to intermittently transport a gas volume from the canister to the wound region via a third conduit and back to the canister via the first conduit in order to press out possible exudates from the first conduit to the canister. A second means analyzes the pressure curve over time of said pressure in the canister and a third means indicates by alarm when said pressure curve differs from a normal cyclical form.

Claims

1. An apparatus for treating a wound with negative pressure, said apparatus comprising:

a wound cover;

a first pump for providing said negative pressure at a chosen pressure level to the wound;

a canister;

a first conduit between the wound cover and the canister, wherein the first conduit is arranged to connect the wound with the canister during use of the apparatus;

first means for measuring the pressure within the canister;

a second conduit that connects the canister with the first pump;

a circulating pump; and

a third conduit that connects the canister and a wound region of the wound, wherein the circulating pump is arranged to intermittently transport a gas volume from the canister to the wound region via the third conduit and back to the canister via the first conduit in order to press out possible exudates from the first conduit to the canister, wherein a second means is arranged to analyze the pressure curve over time of said pressure in the canister, said pressure curve being intermittently influenced by said transport of the gas volume, and wherein a third means is arranged to indicate by an alarm when said pressure curve differs from a normal cyclical form, wherein the alarm is visible, audible, or visible and audible.

2. The apparatus of claim 1, wherein said circulating pump is time controlled and wherein said circulating pump is arranged to transport said gas volume at regular intervals.

3. The apparatus of claim 1, wherein said circulating pump is controlled by the time required to re-establish the negative pressure to the same level as it was before the last circulation cycle of said gas volume.

4. The apparatus of claim 1, wherein said second means includes a printed circuit board.

5. The apparatus of claim 4, wherein said third means includes a human machine interface with a display.

6. The apparatus of claim 5, wherein the printed circuit board is arranged to control the display for presenting on the display when the first conduit is blocked up, wherein said presentation on the display can be in form of a symbol or in clear text.

7. The apparatus of claim 1, wherein a check valve is arranged in a connecting branch on the wound cover to hinder the gas volume pumped by the circulating pump from reaching the wound.

8. The apparatus of claim 1, wherein said first means for measuring the pressure within the canister is a pressure sensor.

9. The apparatus of claim 8, wherein said pressure sensor is a piezo-electrical sensor.

13. The apparatus of claim 3, wherein the circulating pump is controlled by the time (t₂-t₃) required to reestablish the negative pressure to the same level as it was before the last circulation cycle of said gas volume, wherein t₂ represents a time at which the circulating pump is stopped and the gas volume used to clean the first conduit has been evacuated from the canister, and wherein t₃ represents the time at which the evacuated gas volume is reintroduced in the canister and the negative pressure in the canister has been reestablished.

10. A method for controlling the negative pressure in a wound with the use of an apparatus for treating wounds with negative pressure, the method comprising:

using a first pump to create a negative pressure at a chosen pressure level within a canister, which is connected with the wound via a first conduit;

measuring the pressure in the canister;

intermittently transporting a gas volume with a circulating pump from the canister towards the wound region via a third conduit;

directing said gas volume to the first conduit and back through the first conduit to the canister for pushing possible wound exudates residing in the first conduit to the canister;

analyzing the pressure curve over time of said pressure in the canister, said pressure curve being intermittently influenced by said transport of the gas volume; and

selectively activating an alarm when said pressure curve differs from a normal cyclical form, wherein the alarm is visible, audible, or visible and audible.

11. The method of claim 10, wherein said gas volume is transported through the third conduit with said circulating pump at regular time intervals, and wherein the length of said time interval is chosen for setting maximal allowed difference of the negative pressure within the wound relative to the set pressure in the canister.

12. The method of claim 10, wherein said gas volume is transported through the third conduit with said circulating pump at time intervals of varying length, wherein the length of an individual time interval is controlled by the time required to re-establish the negative pressure to the same level as it was before the last circulation of said gas volume.

14. The method of claim 12, wherein the length of an individual time interval is controlled by the time (t₂-t₃), wherein t₂ represents a time at which the circulating pump is stopped and the gas volume used to clean the first conduit has been evacuated from the canister, and wherein t₃ represents the time at which the evacuated gas volume is reintroduced in the canister and the negative pressure in the canister has been reestablished