Diabetic foot ulcer
Successful treatment using negative pressure in diabetic foot ulcers
Negative pressure wound therapy (NPWT) has recently been recommended in the management of some diabetic foot wounds. It is a non-invasive technique entailing exposure of the wound to subatmospheric pressure (Morykwas and Argenta 1997). Subatmospheric pressure is delivered via a dressing interface (gauze or foam) placed in the wound that is sealed and attached to a speciality pump.
Most clinicians are convinced at the bedside about the value of NPWT in foot ulceration when they see dramatic changes in the characteristics of a wound, such as size, depth and exposed structures. There is now a growing body of evidence that supports the clinical observations. In 2005 Armstrong and Lavery published a landmark study. This study investigated the role of NPWT in 162 patients with diabetes with adequate perfusion who had undergone a partial foot amputation to the trans-metatarsal level. Patients were randomized to NPWT or standard moist wound healing.
Wounds were treated until healing or completion of the112 day active wound healing period. The results showed significantly more subjects healed in the NPWT group. Also the rate of wound healing, based on the time to complete closure and the rate of granulation tissue formation were faster in the NPWT group in comparison to the control group. There was also a trend to towards fewer amputations in the NPWT group. Blume et al (2008) investigated the safety and clinical efficacy of NPWT to treat foot ulcers in diabetic patients in comparison with advanced moist wound therapy (AMWT).
Patients were randomly assigned to either NPWT or AMWT and received standard off-loading therapy as needed. The results showed a greater proportion of foot ulcers achieved complete ulcer closure with NPWT than with AMWT. NPWT patients experienced significantly fewer secondary amputations. In assessing safety, no significant difference between the groups was observed in treatment-related complications.