A dressing for treating a tissue site may include a manifold, a transparent or translucent backing layer disposed over a surface of the manifold, an adherent layer disposed on at least a margin of the backing layer, and a plurality of liquid contact indicators disposed in a spaced array between the manifold and the backing layer. A dressing kit may include the plurality of liquid contact indicators separate from the other elements of the dressing. Therapy systems may include the dressing or a dressing assembled from the dressing kit. Also, methods for monitoring fluid distribution and methods for reducing edema can include the dressing, a dressing assembled from the dressing kit, or at least a portion of the therapy system containing them.

A wound dressing according to certain embodiments includes an adhesive layer for adhering the wound dressing adjacent to a wound, a wound contact layer for contacting the wound, a backing layer comprising a port, a tube having a first end connected with the port and an opposite second end, a first fitting connected to the second end of the tube, the first fitting configured for connection with a second fitting of the negative pressure wound therapy system to apply a negative pressure via the port, and a filter disposed within the first fitting. In certain embodiments, the filter is formed of polyethersulfone (PESU) and has an average pore size of at least 2 microns.

Pump cassettes, wound-treatment apparatuses and methods. In some embodiments, a pump cassette comprises: a pump body having a pump chamber, an inlet valve in fluid communication with the pump chamber, and an outlet valve in fluid communication with the pump chamber; a diaphragm coupled to the pump body such that the diaphragm is movable to vary a volume in the pump chamber; and an identifier configured to store one or more properties of the pump cassette such that the identifier is readable by an automated reader to determine the one or more properties. In some embodiments, the pump cassette is configured to be removably coupled to a wound-treatment apparatus having an actuator such that the actuator can be activated to move the diaphragm.

A reduced pressure treatment apparatus includes a charging chamber storing a first pressure less than an ambient pressure and a regulated chamber storing a second pressure less than the ambient pressure. The first pressure is less than the second pressure. A conduit provides fluid communication between the regulated chamber and the charging chamber. A regulator member is operably associated with the conduit to prevent fluid communication through the conduit when the second pressure is less than or equal to a desired therapy pressure and to allow fluid communication through the conduit when the second pressure exceeds the desired therapy pressure.

Systems and methods are presented for providing reduced pressure to and monitoring pressure at a plurality of tissue sites using a plurality of pressure management devices. The pressure management devices are associated with a plurality of sensing conduits that fluidly couple the pressure management devices and the plurality of tissue sites. Other systems, methods, and devices are disclosed.

A system for treating a tissue site includes a pressure source to apply reduced pressure, and a manifold in fluid communication with the pressure source to provide reduced pressure to the tissue site. The system includes a drape for adhering to the tissue site to cover the tissue site and the manifold. The drape has a film layer having a thickness less than about 15 microns, and an adhesive coupled to the film layer. The adhesive seals the film layer to the tissue site to create a sealed space having the manifold therein. The adhesive is sufficiently thick to limit leaks between the film layer and the tissue site.

Some illustrative embodiments of a dressing for treating a tissue site may include a fluid hub, a plurality of elongate fluid members, and a separable joint. The plurality of elongate fluid members may be positioned in fluid communication with the fluid hub. Each of the plurality of elongate fluid members may include a proximal end, a distal end, and an elongate side between the proximal end and the distal end. The elongate side of the elongate fluid members may extend longitudinally outward from the fluid hub. The separable joint may be coupled between the elongate side of one of the plurality of elongate fluid members and the elongate side of another of the plurality of elongate fluid members. Other dressings, systems, and methods are disclosed.

Systems, apparatuses, and methods for providing negative pressure with instillation fluids to a tissue site are disclosed. Some embodiments are illustrative of an apparatus or system for delivering negative-pressure and/or therapeutic solution of fluids to a tissue site, which can be used in conjunction with sensing properties of fluids extracted from a tissue site and/or instilled at a tissue site. For example, a system may comprise a tissue interface adapted to be coupled to a source of instillation fluid and a dressing interface having a therapy cavity that includes a pH sensor, a humidity sensor, a temperature sensor, and a pressure sensor embodied on a single pad within the dressing interface to provide data indicative of acidity, humidity, temperature and pressure at the tissue site. Such apparatus may further comprise algorithms for processing such data for detecting leakage and blockage conditions as well as providing information relating to the progression of healing of wounds at the tissue site. An illustrative method may comprise disposing the tissue interface at the tissue site and the therapeutic cavity in fluid communication with the tissue interface. The method may further comprise instilling fluid to the therapy cavity and then sensing the pressure, humidity, temperature, and the pH of the fluids adjacent the tissue interface. The method may further comprise determining various flow characteristics of the system by using a processing element electrically coupled to the sensors for transmitting property signals from the sensors to a controller configured to assess the property signals in order to identify the flow characteristics.

A portable system for subatmospheric pressure therapy in connection with healing a surgical wound, including a wound dressing dimensioned for positioning relative to a wound bed of a subject and a subatmospheric pressure mechanism dimensioned to be carried or worn by the subject. The subatmospheric pressure mechanism includes a housing having a control unit adapted to draw a vacuum and a canister associated with the housing. The canister has a collection bag disposed therein, which is in fluid communication with the wound dressing to receive exudates from the wound bed. The collection bag is adapted to expand upon receipt of the fluids and has means to release gas from within the collection bag in connection with operation of the control unit. With this arrangement, the canister is attitude independent, i.e., the canister may be positioned on edge, on its side or on its end etc. while still maintaining operation of the control unit. The collection bag may include a hydrophobic vent or material for releasing the gases. In another embodiment, the collection bag comprises a gas permeable material. The collection bag may include one of pleats or bellows.