Combining VAC Therapy With Advanced Modalities: Can It Expedite Healing?
Skin ulceration of the lower extremity affects millions of people in the United States alone and may be secondary to a myriad of etiologies including pressure, metabolic, trauma, venous, arterial and diabetic neuropathy.1 The medical, psychosocial and financial impacts imposed by lower extremity ulcerations are tremendous. The attributable cost for the treatment of chronic lower extremity ulcerations has been estimated to be as high as $3.6 billion dollars per year.2 Medicare expenditures for lower extremity ulcer patients were, on average, three times higher than those for Medicare patients in general.3
In addition, a lack of immediate attention to these wounds can often serve as a prelude to serious health problems due to associated infections that may lead to amputations or induce life-threatening situations.1,4
Wound repair is an orchestra of highly integrated cellular and biochemical responses to injury.5 Certain pathophysiologic and metabolic conditions can alter this normal course of events and lead to impaired or delayed healing, resulting in chronic, non-healing wounds.5 Integrating biotechnological advances with our growing understanding of the complex cellular and biochemical mechanisms of the wound healing process has led to the development of various advanced wound healing modalities.
Many have advocated the use of negative pressure wound therapy (Vacuum Assisted Closure or VAC therapy, Kinetic Concepts Inc.,) in the management of lower extremity ulcerations. Negative pressure wound therapy (NPWT) is the controlled application of subatmospheric pressure to a wound using an electrical pump and specialized wound dressing.6-11 Studies have shown that applying subatmospheric pressure optimizes blood flow, decreases local tissue edema, removes excessive fluid and pro-inflammatory exudates from the wound bed.11 These physiologic changes promote a moist wound healing environment and facilitate the removal of bacteria from the wound.11 Applying sub-atmospheric pressure may also help increase the rate of cell division and subsequent formation of granulation tissue.11
Recently, a number of clinicians have advocated the concomitant use of advanced wound healing modalities with NPWT as a synergistic approach in the armamentarium of wound healing. Accordingly, let us take a closer look at some of the more commonly used modalities that one may combine with NPWT to help treat lower extremity ulcerations.
What The Literature Reveals About Combining Hyperbaric Oxygen Therapy With NPWT
Hyperbaric oxygen therapy (HBOT) is an intermittent inhalation therapy in which the patient breathes oxygen at greater than 1 atmosphere of pressure. This modality requires the patient to be in an entirely enclosed pressure chamber for treatments. HBOT relies on the systemic circulation to deliver highly oxygenated blood to target tissues and raise tissue oxygen tensions to levels where one can expect wound healing. HBOT may also potentiate the action of leukocytes and researchers have noted improved healing in living tissues, especially those poor in oxygen.13,14 Numerous studies suggest that HBOT can be an effective adjunct in the management of complicated and compromised wounds.13-17
In a comparative analysis looking at either compromised post-surgical wounds or wounds secondary to arterial insufficiency, Neizgoda et. al., found that the combination of NPWT with HBOT produced results that exceeded those produced when either modality was used alone.18 In addition, the combined use of both therapies helped decrease the average number of HBOT treatments required.18