Negative pressure wound therapy: application, indications and is there more we could use it for?

In the author's veterinary practice negative pressure wound therapy (NPWT) is used in a variety of wound care cases. Publications on the technique date back 16 years, however, only minor changes have been made to the unit itself since it was first used: the unit has been made smaller; there is increased safety due to unit alarming; changes in the dressing associated and the ability for the unit to remove much more fluid (Murphy and Evans, 2012).

Large, contaminated wounds lend themselves to management with NPWT, along with dehiscing surgical wounds (Murphy and Evans, 2012); degloving injuries and skin avulsions are also indications for use along with chronic non-healing wounds. The fluid that is removed during NPWT contains high levels of proteolytic enzymes which if not removed can result in a non-healing wound environment. Less commonly compartment syndromes, for example abdominal or myofascial, are indications for NPWT management (Nolf and Meye-Lindenberg, 2016). Enterocutaneous fistulas now, despite early reservations, respond well to NPWT, and orthopaedic traumatic wounds benefit from this method as granulation tissue is evident on hardware, grafts and meshes (Murphy and Evans, 2012). Best (2014) reported the use of the unit in a slow healing distal extremity — the negative pressure applied to the wound lowers the interstitial pressure, lower than the capillary pressure, which in turn allows the capillaries to reopen and blood flow to the wound to increase.