Negative Pressure Wound Therapy

Excerpt

Negative pressure wound therapy (NPWT) is a unique and versatile wound care system that optimizes wound healing by applying subatmospheric pressure through specialized wound dressings. This approach reduces inflammatory exudate and promotes the formation of granulation tissue. NPWT has evolved since early systems were first introduced in the 19th century. The modern standard NPWT was described by Argenta and Morykwas in 1997 and consists of a porous foam dressing to which continuous or intermittent suction is applied, which can be set to a pressure up to 125 mm Hg. NPWT, also referred to as vacuum-assisted closure (VAC), is effective for both acute and chronic wounds, and is frequently applied to open wounds, including fractures, ulcers, and infected wounds, as well as open surgical wounds. More recently, NPWT been applied to include new closed surgical wounds and skin grafts.

NPWT reduces edema and seroma formation, promotes granulation tissue formation, and is believed to decrease the risk of surgical wound dehiscence in high-risk sites. Although the evidence supporting the use of NPWT in closed incisions remains equivocal, its use has increased across various clinical settings, including complex arthroplasty and wounds at high risk of dehiscence or infection. Specifically, this practice has been associated with reductions in infection sites, morbidity, and mortality among those undergoing vascular surgery procedures. NPWT has also been shown to reduce wound infections and dehiscence rates in patients undergoing vulvar surgery.

The wound dressing system can be placed in the operating room, at the bedside, or in an examination room. Pressure settings are tailored to different types of wounds. The foam dressing is derived from either polyurethane (black) or polyvinyl alcohol (white) and can be silver impregnated. Disposable systems, whether battery-operated or mechanical suction-only, are typically used for smaller wounds in ambulatory patients. Negative pressure systems may also be used in conjunction with saline or antibiotic instillation into wounds to enhance the delivery of these therapies to the wound beds.