Blockage and leak detection in multiple dressing reduced pressure wound therapy systems
Embodiments of apparatuses and methods for providing negative pressure wound therapy to multiple wounds are disclosed. In some embodiments, presence of blockage in one or more fluid flow paths connecting a negative pressure source to one or more dressings can be performed. Determination of a blockage can be performed based on comparing one or more pressure measurements to at least one threshold. The at least one threshold can be determined based on detected capacities of the one or more dressings.
1 . A negative pressure wound therapy apparatus comprising:
a negative pressure source configured to couple, via a plurality of fluid flow paths, to a plurality of wound dressings and provide negative pressure to the plurality of wound dressings, the plurality of fluid flow paths comprising:
a first fluid flow path configured to fluidically connect a first wound dressing to the negative pressure source; and
a second fluid flow path configured to fluidically connect a second wound dressing to the negative pressure source;
a pressure sensor configured to obtain pressure measurements associated with the plurality of fluid flow paths; and
a controller configured to operate the negative pressure source, the controller further configured to:
determine an aggregate fluid retention capacity of the first and second wound dressings;
determine a blockage threshold based at least in part on the aggregate fluid retention capacity;
detect presence of a blockage in at least one of the first or second fluid flow paths based at least in part on comparing at least some of the pressure measurements to the blockage threshold; and
provide an indication of the blockage in response to determining that the blockage threshold is satisfied.
2 . The negative pressure wound therapy apparatus of claim 1 , wherein the controller is further configured to determine the aggregate fluid retention capacity based on a duration of time for achieving a negative pressure setpoint following activation of the negative pressure source.
3 . The negative pressure wound therapy apparatus of claim 2 , wherein the controller is further configured to deactivate the negative pressure source in response to determining that the negative pressure setpoint has been achieved.
4 . The negative pressure wound therapy apparatus of claim 2 , wherein the duration of time is inversely proportional to the aggregate fluid retention capacity.
5 . The negative pressure wound therapy apparatus of claim 1 , wherein the controller is further configured to:
determine a rate of pressure change in the first and second fluid flow paths over a duration of time based on at least some of the pressure measurements; and
determine the aggregate fluid retention capacity based on the rate of pressure change.
6 . The negative pressure wound therapy apparatus of claim 5 , wherein the rate of pressure change is inversely proportional to the aggregate fluid retention capacity.
7 . The negative pressure wound therapy apparatus of claim 1 , wherein the controller is configured to determine peak-to-trough pressure associated with the plurality of fluid flow paths and detect presence of the blockage based on comparing the peak-to-trough pressure to the blockage threshold.
8 . The negative pressure wound therapy apparatus of claim 1 , wherein the controller is further configured to:
determine a leak threshold based at least in part on the aggregate fluid retention capacity;
detect presence of a leak in at least one of the first or second fluid flow paths based at least in part on comparing at least some of the pressure measurements to the leak threshold; and
provide an indication of the leak in response to determining that the leak threshold is satisfied.
9 . The negative pressure wound therapy apparatus of claim 1 , wherein the controller is further configured to:
based on at least some of the pressure measurements, determine a remaining capacity of at least one of the first or second wound dressings; and
provide an indication of the remaining capacity.
10 . The negative pressure wound therapy apparatus of claim 1 , wherein the blockage indicates that at least one of the first or second wound dressings has been filled to a threshold capacity that is less than a total fluid absorption capacity of the at least one of the first or second wound dressings.
11 . A method of operating a negative pressure wound therapy apparatus comprising:
operating a negative pressure source configured to couple, via a plurality of fluid flow paths, to a plurality of wound dressings comprising a first wound dressing and a second wound dressing, the plurality of fluid flow paths comprising a first fluid flow path configured to fluidically connect the first wound dressing to the negative pressure source and a second fluid flow path configured to fluidically connect the second wound dressing to the negative pressure source;
determining an aggregate fluid retention capacity of the first and second wound dressings; and
at a first time:
determining a blockage threshold based at least in part on the aggregate fluid retention capacity;
detecting presence of a blockage in at least one of the first or second fluid flow paths based at least in part on comparing at least some pressure measurements associated with the plurality of fluid flow paths to the blockage threshold and determining that the blockage threshold is satisfied; and
responsive to determining that the blockage threshold is satisfied, providing an indication of the blockage,
wherein the method is performed under control of a controller of the negative pressure wound therapy apparatus.
12 . The method of claim 11 , further comprising, determining the aggregate fluid retention capacity based on a duration of time for achieving a negative pressure setpoint following activation of the negative pressure source.
13 . The method of claim 12 , further comprising:
determining that the negative pressure setpoint has been achieved; and
deactivating the negative pressure source in response to determining that the negative pressure setpoint has been achieved.
14 . The method of claim 12 , wherein the duration of time is inversely proportional to a combined first and second fluid retention capacities of the first and second wound dressing.
15 . The method of claim 11 , further comprising:
determining a rate of pressure change in the first and second fluid flow paths based on at least some pressure measurements associated with the plurality of fluid flow paths; and
determining the aggregate fluid retention capacity based on the rate of pressure change.
16 . The method of claim 15 , wherein the rate of pressure change is inversely proportional to the aggregate fluid retention capacity.
17 . The method of claim 11 , further comprising, determining peak-to-trough pressure associated with the plurality of fluid flow paths and detecting presence of the blockage based on comparing the peak-to-trough pressure to the blockage threshold.
18 . The method of claim 11 , further comprising:
at a second time:
determining a leak threshold based at least in part on the aggregate fluid retention capacity;
detecting presence of a leak in at least one of the first or second fluid flow paths based at least in part on comparing at least some pressure measurements associated with the plurality of fluid flow paths to the leak threshold and determining that the leak threshold is satisfied; and
in response to determining that the leak threshold is satisfied, providing an indication of the leak.
19 . The method of claim 11 , further comprising:
based on at least some pressure measurements associated with the plurality of fluid flow paths, determining a remaining capacity of at least one of the first or second wound dressings; and
providing an indication of the remaining capacity.
20 . The method of claim 11 , wherein the blockage indicates that at least one of the first or second wound dressings has been filled to a threshold capacity that is less than a total fluid absorption capacity of the at least one of the first or second wound dressings.