T he etiology of chronic venous ulceration is not fully understood. The pathway from venous insufficiency to ulceration remains a debatable issue. Both the fibrin cuff 1 and the white blood trapping theory 2 have tissue hypoxia in the microcirculation as a common denominator. Hypoxia impedes wound healing by decreasing fibroblast proliferation, collagen syn- thesis, and angiogenesis. 3,4 Transcutaneous oximetry (TCOM) is a simple, noninvasive tool to measure tissue oxygenation. 5 This technique avoids the risks of invasive measurement such as tissue disruption around the wound, infection, and exacerbation of nonhealing lesions. TCOM estimates tissue The Effect of Vacuum-assisted Closure on the Tissue Oxygenation of Venous Ulcers: A Pilot Study Manar Khashram, MB ChB; Justin A. Roake, MB ChB, DPhil, FRCS, FRACS(Vasc); David R. Lewis, MB ChB, MD, EBSQ(Vasc), FRACS, FRCS WOUNDS 2009;21(9):249–253 From the Department of Vascular, Endovascular, and Transplant Surgery, University of Otago, Christchurch School of Medicine, New Zealand Address correspondence to: Manar Khashram University of Otago, Christchurch School of Medicine PO Box 4345 Christchurch 8140 New Zealand Phone: +64 29 9323931 Email: manar.khashram@gmail.com Disclaimer: All VAC equipment was pro- vided by Intermed-KCI. This did not influence the study design, data analy- sis, or submission of the manuscript for publication. Abstract: Background. Vacuum-assisted closure (V.A.C. ® Therapy, KCI, San Antonio, TX) has been widely used to increase the healing rate of a variety of wounds. It has been hypothesized that one of the actions of VAC is to increase perfusion and subsequent oxygenation of tissue. The aim of the present study was to investigate the effect of VAC ther- apy on transcutaneous oximetry measurements (TCOM) of skin sur- rounding chronic venous ulcers. Methods. This was a prospective, experimental pilot study. Patients undergoing compression therapy were recruited from a community wound clinic. All patients had ankle- brachial pressure indices (ABPI) > 0.8. Three TCOM values were taken from around the ulcer and a reference TCOM was taken from the chest. Negative pressure was applied on the ulcer at 125-mmHg con- tinuous subatmospheric pressure and four-layer compression bandag- ing over the VAC drapes. The duration of the study was 6 days. On day 6, dressings were removed and TCOM was repeated at the same skin sites. Results. Fourteen of the 17 patients completed the trial. The median age was 73 years (range 49–85). No significant difference was found in oxygen partial pressure pre-and post-VAC therapy around the ulcer site (mean 41.5 mmHg versus 40 mmHg [P = 0.67]). There was a significant difference in TCOM between the reference point and the periwound area (mean 60.5 versus 40 [P < 0.0005]). Conclusion. This pilot study suggests that VAC therapy does not change oxygen partial pressure around venous ulcers. TCOM of the skin around ulcers were low despite normal ABPIs. Vol. 21, No. 9 September 2009 249 ORIGINAL RESEARCH DO NOT REPRODUCE