Chapter 15: Negative Pressure Wound Therapy

INTRODUCTION

Negative pressure wound therapy (NPWT), also known as topical negative pressure therapy (TNP),^1,2 and negative pressure wound care (NPWC),³ were first documented as an adjunct treatment for open wounds in the early 1990s.² By 2004 this active therapy was reported as standard of care for a variety of diagnoses in modern wound management.¹ Through the application of a closed wound dressing and attached suction, NPWT applies controlled, subatmospheric pressure to open wounds and has been shown to provide the following benefits for wound healing:

• Promotion of moist wound healing⁴

• Reduction of edema and interstitial fluid^1,4,5

• Increased local perfusion^6–8

• Approximation of wound edges^4,9

• Stimulation of granulation tissue formation^9,10

• Reduction in bacterial load^9,11

• Reduction in the frequency of dressing changes¹²

Since its acceptance into evidence-based wound management, NPWT has been utilized to treat a wide variety of acute and chronic wounds¹³ including acute traumatic and surgical^2,14 wounds healing by primary and secondary intention; burns^15,16; and chronic wounds associated with venous insufficiency,^3,13 diabetes,^3,10,17,18 and pressure.¹⁹ Events such as the devastating 2010 earthquake in Haiti¹⁵ and war in the Middle East^15,20,21 have also shown how the benefits of NPWT can positively influence limb salvage rates and decrease morbidity and mortality in mass casualty and high-energy injury situations.

A NPWT system consists of a pump unit that provides suction, a wound filler that transfers negative pressure to the wound bed and allows flow of fluids from the wound, a transparent occlusive sheet that covers the wound filler and creates an airtight seal, and flexible tubing that delivers suction and serves as a conduit for removal of drainage and wound debris.²² Wound fluids are collected in a disposable container that is attached to the pump (FIGURE 15-1). TABLE 15-1 further describes NPWT components.