Wound therapy system with in-line orifice
A wound therapy system includes a dressing sealable over a wound, a conduit comprising a first inner diameter, coupled to the dressing, and fluidly communicable with the wound space, and a canister fluidly communicable with the conduit. A therapy unit is coupled to the canister and includes a pump, a sensor configured to measure a pressure, a valve controllable between an open position and a closed position, and a control circuit. The control circuit is configured to control the pneumatic pump to remove air to establish a negative pressure, control the valve to repeatedly alternate between the open closed positions to allow a controlled rate of airflow through the valve, receive measurements of the pressure from the sensor, and determine a volume of the wound space based on the pressure measurements. A portion of the conduit comprises a second inner diameter that is less than the first inner diameter.
1 . A wound therapy system, comprising:
a dressing sealable over a wound and defining a wound space;
a conduit comprising a first inner diameter, wherein the conduit is fluidly communicable with the wound space;
a canister fluidly communicable with the conduit, wherein the canister, the conduit, and the dressing define a sealed space comprising the wound space;
a therapy unit coupled to the canister and comprising:
a pneumatic pump fluidly communicable with the sealed space;
a sensor configured to measure a pressure in the sealed space;
a valve positioned between the sealed space and surrounding environment and controllable between an open position and a closed position; and
a control circuit configured to:
control the pneumatic pump to remove air from the sealed space to establish a negative pressure in the sealed space;
receive measurements of the pressure in the sealed space from the sensor; and
determine a volume of the wound space based on the measurements of the pressure; and
a bellows fluidly communicable with the pneumatic pump and the canister, the bellows comprising:
a plate having a first end and a second end, wherein the plate defines a plate lumen having a plate lumen diameter extending between the first end and the second end;
an insert defining an insert lumen extending through the insert and having an insert lumen diameter, wherein the insert lumen diameter is less than the plate lumen diameter, and wherein the insert is disposed at the first end of the plate such that the insert lumen aligns with the plate lumen; and
an overmold disposed over the insert and at least partially over a length of the plate defined between the first end and the second end of the plate, wherein the overmold substantially secures the insert relative the plate.
2 . The wound therapy system of claim 1 , wherein the conduit is coupled to the dressing, and wherein the overmold is configured to sealably couple the plate with the canister.
3 . The wound therapy system of claim 1 , wherein a location of the bellows is between the dressing and the therapy unit and the overmold is configured to sealably couple the plate with the therapy unit.
4 . The wound therapy system of claim 1 , wherein the control circuit is further configured to control the valve to repeatedly alternate between the open position and the closed position to allow a controlled rate of air flow through the valve, wherein the control circuit is further configured to determine a pressure decay curve based on the measurements of the pressure.
5 . The wound therapy system of claim 1 , wherein the insert lumen diameter ranges between a first value of approximately 0.1 mm and a second value of approximately 1.0 mm.
6 . The wound therapy system of claim 1 , wherein the valve is positioned between the pneumatic pump and the canister.
7 . The wound therapy system of claim 1 , wherein the bellows is positioned between the pneumatic pump and the canister.
8 . The wound therapy system of claim 1 , wherein the control circuit is further configured to determine an amount of instillation fluid to be supplied to the wound space from an instillation fluid source based on the determined volume of the wound space.
9 . The wound therapy system of claim 1 , wherein the insert lumen diameter ranges between a first value of approximately 0.33 mm and a second value of approximately 0.43 mm.
10 . A wound therapy system, comprising:
a dressing configured for placement over a wound;
a therapy unit having a pneumatic pump operably coupled to a removable canister;
a conduit coupled to the dressing and the canister and defining a flowpath therethrough; and
a bellows disposed within the flowpath and operable to maintain a restriction to a flow through the flowpath, the bellows comprising:
a plate defining a plate lumen having a plate lumen diameter;
an insert defining an insert lumen having an insert lumen diameter, wherein the insert lumen diameter is less than the plate lumen diameter, and wherein the insert lumen is aligned with the plate lumen; and
an overmold disposed over the insert and at least partially over a length of the plate, wherein the overmold substantially secures the insert relative the plate.