Patent ID: 8617129

Claim:
Apparatus for the provision of topical negative pressure therapy to a wound site, the apparatus comprising: vacuum generating means being operably connected to a dressing at said wound site by aspiration conduit means; pressure sensing conduit means in fluid communication with said aspiration conduit means at a junction adjacent said dressing; first pressure sensing means between said junction and said vacuum generating means; second pressure sensing means operably associated with said pressure sensing conduit means; a valve associated with said pressure sensing conduit means; diagnostic means in communication with said first and second pressure sensing means; and control means in communication with said diagnostic means for controlling pressure in said aspiration and said pressure sensing conduit means, wherein the control means is configured to: detect a blockage in the aspiration conduit means based on comparison of a pressure difference between pressure sensed by the first pressure sensing means and pressure sensed by the second pressure sensing means with a pressure difference threshold; open the valve in response to detecting the blockage; close the valve if the pressure difference falls to substantially zero after expiration of a first time interval; and activate a blockage alarm if the pressure difference does not fall to substantially zero after expiration of a second time interval, the blockage alarm configured to indicate the blockage in the aspiration conduit means.