A negative pressure wound therapy device includes at least one piezoelectric pump and a control circuit. The control circuit is configured to generate a first control signal to control operation of the at least one piezoelectric pump, the control signal having a first root mean square (RMS) voltage, transmit the first control signal to the at least one piezoelectric pump, identify at least one of a change of state of the at least one piezoelectric pump or an expiration of a duration of time associated with operation of the at least one piezoelectric pump, responsive to identifying the at least one of the change of state or the expiration of the duration of time, generate a second control signal having a second RMS voltage less than the first RMS voltage, and transmit the second control signal to the at least one piezoelectric pump.

This disclosure includes negative pressure wound therapy dressings with local oxygen generation for topical wound therapy. The dressings (18) for facilitating delivery of oxygen and application of negative pressure to target tissue include a manifold (46) that defines a plurality of gas passageways (50) and is configured to allow communication of oxygen to the target tissue; an oxygen-generating material (146) that is configured to release oxygen when exposed to water; a gas-occlusive layer (74) configured to be disposed over the manifold and the oxygen-generating material and coupled to tissue surrounding the target tissue such that an interior volume containing the manifold and the oxygen-generating material is defined between the gas-occlusive layer and the target tissue; and a port (94) coupled to the gas-occlusive layer and configured to be coupled to a negative pressure source.

A valve arrangement for administering an instillation and/or negative pressure therapy through at least a first wound dressing and a second wound dressing includes a valve arrangement including a first flow path, a first valve, a second flow path, and a second valve. The first flow path extends between a source port and a first wound dressing port structured for fluid communication with the first wound dressing. The first valve is positioned in the first flow path. The second flow path extends between the source port and a second wound dressing port structured for fluid communication with the second wound dressing. The second valve is positioned in the second flow path.

A negative pressure wound therapy device includes a piezoelectric pump, a state detector configured to detect a state of the pump, and a control circuit configured to transmit a first control signal for a first period having a first RMS voltage greater than or equal to a threshold voltage at which driving the pump for a second period greater than the first period can cause the pump to emit sound at a magnitude greater than a sound threshold; receive a first indication of the state; determine if the pump is in a leak condition; transmit, responsive to the pump not being in the leak condition, a second control signal having a second RMS voltage less than the first RMS voltage; and transmit, responsive to the pump being in the leak condition, a third control signal having a third RMS voltage greater than the second RMS voltage.

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 dressing interface for a negative-pressure treatment system includes a housing. The housing includes an entry surface having first channels. The dressing interface also includes a primary conduit through the housing and terminating on the entry surface, an ancillary conduit through the housing and terminating on the entry surface, and a base coupled to the housing. The base includes an aperture, and a plurality of stand-offs having rounded surfaces. The stand-offs defines second channels configured to facilitate flow of liquid to the first channels through the aperture.

A negative pressure wound therapy system includes at least one sensor coupled to a wound dressing for a wound of a patient, and a control circuit. The at least one sensor is configured to output an indication of a displacement of the wound dressing. The control circuit is configured to receive the indication of the displacement of the wound dressing, calculate a therapy parameter corresponding to the indication of the displacement, and output the therapy parameter.

In one example embodiment, an apparatus for treating a tissue site may include a contact layer formed from a compressible material. The contact layer may include a plurality of apertures extending at least partially through the contact layer. The contact layer may be configurable such that at least a portion of the apertures include a first plurality of orifices having a diameter in a first diameter range and such that at least a portion of the apertures include a second plurality of orifices having a diameter in a second diameter range. The first diameter range may be from about 2 mm to about 6 mm. The second diameter range may be from about 8 mm to about 15 mm. The apparatus may include a cover configured to form a sealed space including the contact layer and the tissue site.

Systems, apparatuses, and methods for providing negative pressure and/or 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, an apparatus may comprise a dressing interface or connector that includes a pH sensor, a humidity sensor, a temperature sensor and/or a pressure sensor embodied on a single pad within the connector and proximate the tissue site to provide data indicative of acidity, humidity, temperature and pressure. Such apparatus may further comprise algorithms for processing such data for detecting leakage and blockage as well as providing information relating to the progression of healing of wounds at the tissue site. An illustrative method may comprise positioning a dressing interface having a pH sensor, a temperature sensor, a humidity sensor, and a pressure sensor at a tissue site, and applying reduced pressure to the dressing interface to draw fluids from the tissue interface in contact with the sensors to sense the pH, temperature, humidity, and pressure properties of the fluids flowing from the tissue site. The method may further comprise providing fluid data indicative of such properties to a control device for processing the fluid data and transmitting the data to another component in the system.

Negative pressure wound therapy systems, apparatuses, and methods for operating the systems and apparatuses are disclosed. In some cases, the system can include a dressing having electronic circuitry that wirelessly communicates a dressing identifier and/or other dressing information to a controller of a pump assembly of the system. The controller can automatically modify one or more operational parameters of the pump assembly based on the dressing identifier and/or other dressing information wirelessly communicated. Duration of time over which the dressing has been in use can be monitored and provision of therapy by the pump assembly can be disabled responsive to a determination that the duration of time has reached operational lifetime of the dressing.