In some illustrative examples, a bridge suitable for treating a tissue site may include a bridge sealing member and one or more bridge wicking layers. The bridge sealing member may extend along a length of the bridge, and may define an internal passageway in fluid communication between a receiving end of the bridge and a transmitting end of the bridge. The one or more bridge wicking layers may be disposed within the internal passageway of the bridge sealing member. Other apparatus, systems, and methods are disclosed.

Negative pressure wound therapy apparatuses and dressings, and systems and methods for operating such apparatuses for use with dressings are disclosed. In some embodiments, controlling the delivery of therapy can be based on monitoring and detecting various operating conditions. An apparatus can have a controller configured to monitor the duty cycle of a source of negative pressure and, based on the monitored duty cycle, determine whether a leak is present. The controller can be configured to provide an indication that a leak is present. For example, the controller can be configured to suspend and/or pause the delivery of therapy, and to restart the delivery of therapy due to a timeout, request from a user, etc. In addition, the controller can be configured to pause and/or restart the delivery of therapy upon a request from the user, such as in response to the user operating a switch.

Leak location devices and methods of using leak location devices that can be used in conjunction with negative pressure wound therapy systems are disclosed. In some embodiments, a leak location device can include a microphone for detecting sound pressure produced by a leak. Detected sound pressure can be compared to a threshold, which can correspond to background or ambient sound pressure. Background or ambient sound pressure can correspond to sound produced by a negative pressure source. The leak detection device can include a display configured to visually depict the detected sound, and a light source which creates a visual depiction of the coverage angle of the microphone.

Systems and methods for controlling a pump system for use in negative pressure wound therapy are described herein. In some embodiments, a method for controlling a pump system includes applying a drive signal to a pump assembly of the pump system, the drive signal alternating between a positive amplitude and a negative amplitude and the drive signal having an offset, and sampling a pressure within a fluid flow path configured to connect the pump system to a wound dressing configured to be placed over a wound during one or more time intervals. Each of the one or more time intervals can occur when the drive signal is approximately at an amplitude equal to one or more sampling amplitudes.

A method and apparatus are disclosed for dressing a wound. The apparatus comprises a sealing layer comprising at least one orifice, an absorbent layer over the sealing layer, absorbing wound exude and a liquid impermeable, gas permeable filter layer over the absorbent layer.

Embodiments of negative pressure wound therapy systems, apparatuses, and methods for operating the systems and apparatuses are disclosed. In some embodiments, the apparatus includes a negative pressure source, a connector port, at least one switch, and a controller. The negative pressure source is connected through the connector port to either (i) a wound dressing having a canister configured to store fluid aspirated from the wound or (ii) a wound dressing without a canister between the connector port and the wound dressing. The controller determines, based on a signal received from the at least one switch, whether the canister is positioned in the fluid flow path and adjusts one or more operational parameters of negative pressure wound therapy based on the determination. The switch is activated by the connection of either the canister or canisterless wound dressing to the apparatus.

A wound dressing comprising: an air-impermeable backing sheet having an aperture for attachment of a suction element; an air-permeable screen layer on a wound facing side of the backing sheet; and a substantially air-impermeable hydrogel layer extending across a wound facing side of said screen layer and joined in substantially airtight fashion to a periphery of said backing sheet around said screen layer. Also provided is a wound treatment system comprising a wound dressing according to the invention and a source of suction in fluid communication with said aperture.

A wound dressing, a method of manufacturing a wound dressing, and a method of treating a patient are disclosed. The wound dressing may include an absorbent layer for absorbing wound exudate; and an obscuring element for at least partially obscuring a view of wound exudate absorbed by the absorbent layer in use.

A liquid collection device for use in drawing liquid from an opening in a body of a person or an animal. The device includes a perforated container, and an outlet port. The perforated container defines a chamber shaped to collect liquid drawn into the chamber through perforations in the container. The outlet port enables liquid to be drawn from the chamber by a partial vacuum applied at the outlet port. The container is configured to receive wicking material that covers at least some of the perforations and is also configured and dimensioned for placement of the wicking material in, or over approximately an exposed breadth of, an opening in a person or an animal, so that upon said placement of the container with at least some of the perforations being covered by said wicking material, when a partial vacuum is applied at the outlet port, liquid can be drawn from said opening through the wicking material and into the chamber and from the chamber through the outlet port.