Apparatus and methods for pressure management within a wound chamber
View Patent ↗A wound therapy apparatus disclosed herein includes a wound interface sealingly securable to a skin surface around a wound bed to form an enclosed space over the wound bed. An inflow fluid pathway and an outflow fluid pathway communicate fluidly with the enclosed space through an inflow port and an outflow port, respectively. The inflow port and the outflow port may be in spaced relation to define a flow path within the enclosed space equivalent in length to a characteristic length of the enclosed space. Pressure sensors may be in communication with the inflow fluid pathway and the outflow fluid pathway to detect inflow pressure p in , and outflow pressure p out .
1. A wound therapy apparatus, comprising:
a wound interface sealingly securable to a skin surface around a wound bed to form an enclosed space over the wound bed;
an inflow port disposed about the wound interface to form a portion of an inflow fluid pathway that communicates an inflow fluid into the enclosed space;
an outflow port disposed about the wound interface to form a portion of an outflow fluid pathway that communicates an outflow fluid out of the enclosed space, the outflow port in spaced relation with the inflow port to define a flow path within the enclosed space equivalent to a characteristic length of the enclosed space;
an inflow pressure sensor in communication with the inflow fluid pathway to detect an inflow pressure p in of the inflow fluid;
an outflow pressure sensor in communication with the outflow fluid pathway to detect an outflow pressure p out of the outflow fluid; and
wherein the inflow pressure p in and the outflow pressure p out in combination are indicative of a pressure p a within the enclosed space.
2. The apparatus of claim 1 , wherein the enclosed space has a circular shape and the characteristic length is defined as a radius of the circular shape.
3. The apparatus of claim 1 , wherein the enclosed space has a rectangular shape and the characteristic length is defined as a diagonal of the rectangular shape.
4. The apparatus of claim 1 , wherein the wound interface has a square shape and the characteristic length is defined as a diagonal of the square shape.
5. The apparatus of claim 1 , wherein the wound interface has an irregular polygonal shape and the characteristic length is defined as a longest diagonal of the irregular polygonal shape.
6. The apparatus of claim 1 , wherein the wound interface has a U shape and the characteristic length is defined from end to end of the U shape.
7. The apparatus of claim 1 , further comprising:
a controller in operative communication with the inflow pressure sensor and with the outflow pressure sensor to receive data from the inflow pressure sensor and from the outflow pressure sensor, the data indicative of the inflow pressure p in of the inflow fluid, a time rate of change of the inflow pressure
dp
in
dt
,
the outflow pressure p out of the outflow fluid, and a time rate of change of the outflow pressure
dp
out
dt
;
and
wherein the controller determines an operational condition of said wound therapy apparatus using the data.
8. The apparatus of claim 7 , wherein the operational condition is indicated by |p in −p out |<ε where ε represents a sensitivity and
dp
in
dt
-
dp
out
dt
>
δ
where δ represents another sensitivity.
9. The apparatus of claim 7 , wherein the operational condition is indicated by |p in −p out |>ε where ε represents a sensitivity and
dp
in
dt
-
dp
out
dt
>
δ
where δ represents another sensitivity.
10. The apparatus of claim 9 , wherein a pulse of the input fluid is input into the enclosed space to clear an occlusion from the outflow fluid pathway upon indication of the operational condition.
11. The apparatus of claim 7 , wherein the operational condition is indicated by |p in −p out |<ε and by
dp
out
dt
-
dp
in
dt
>
δ
where ε represents a sensitivity and δ represents another sensitivity.
12. The apparatus of claim 11 , wherein the pressure p a within the enclosed space is decreased below ambient pressure p amb upon indication of the operational condition.
13. The apparatus of claim 7 , wherein the operational condition is indicated by
p
in
-
p
out
<
ɛ
and
by
dp
out
dt
>
δ
where ε represents a sensitivity and δ represents another sensitivity.
14. A wound therapy apparatus, comprising:
a wound interface sealingly securable to a skin surface around a wound bed to form an enclosed space over the wound bed;
an inflow fluid pathway that communicates the inflow fluid into the enclosed space;
an outflow fluid pathway that communicates an outflow fluid out of the enclosed space;
a sensor in communication with the inflow fluid pathway and in communication with the outflow fluid pathway to detect data indicative of the inflow pressure p in of the inflow fluid, a time rate of change of the inflow pressure
dp
in
dt
,
the outflow pressure p out of the outflow fluid, and a time rate of change of the outflow pressure
dp
out
dt
;
and
a processor in communication with the sensor to determine an operational condition of said wound therapy apparatus from the data.
15. The apparatus of claim 14 , wherein the operational condition is indicated by |p in −p out |<ε where ε represents a sensitivity and
dp
in
dt
-
dp
out
dt
>
δ
where δ represents another sensitivity.
16. The apparatus of claim 14 , wherein the operational condition is indicated by |p in −p out |>ε where ε represents a sensitivity and
dp
in
dt
-
dp
out
dt
>
δ
where δ represents another sensitivity.
17. The apparatus of claim 16 , wherein a pulse of the input fluid is input into the enclosed space to clear an occlusion from the outflow fluid pathway upon indication of the operational condition.
18. The apparatus of claim 14 , wherein the operational condition is indicated by |p in −p out |<ε and by
dp
out
dt
-
dp
in
dt
>
δ
where ε represents a sensitivity and δ represents another sensitivity.
19. The apparatus of claim 18 , wherein the pressure p a within the enclosed space is decreased below ambient pressure p amb upon indication of the operational condition.
20. The apparatus of claim 14 , wherein the operational condition is indicated by |p in −p out |<ε and by
dp
out
dt
>
δ
where ε represents a sensitivity and δ represents another sensitivity.