The Effect of Vacuum-assisted Closure on the Tissue Oxygenation of Venous Ulcers: A Pilot Study
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Patients were diagnosed as having superficial venous incompetence with clinical examination and a hand held Doppler (Level 1 investigation).11 The inclusion criterion was venous ulcer size > 1 cm2. Exclusion criteria were ankle-brachial pressure index (ABPI) < 0.8, previous VAC therapy, current smokers, lymphedema, severe lipodermatosclerosis (LPS), recurrent ulcers, previous deep vein thrombosis or known deep venous incompetence, body mass index > 35, and presence of infected, malignant, or vasculitic ulcers. Lipodermatosclerosis was defined as “mild” if the skin around the ulcer was involved, and “moderate” if the entire ankle was affected. All subjects were ambulatory and were treated as an outpatient. All participants were provided with trial information sheets and written consent was obtained. Ethical approval was granted by the regional ethics committee.
Materials. All VAC equipment was provided by Intermed-Kinetic Concepts, Inc (Auckland, New Zealand). VAC therapy consisted of polyurethane foam (black foam) dressing with a pore size of 400 µm–600 µm, adhesive draping, and an evacuation tube connected to the VAC® Freedom or MiniVAC® system. Once the black foam dressing had been applied, therapy was commenced at 125-mmHg subatmospheric pressure continuously. Four-layer compression bandaging using the Charing Cross method (orthopedic wool, support crepe bandage, class 3a bandage plus cohesive bandage) providing 40 mmHg at the ankle graduating to 17 mmHg below the knee, was applied over the sealing drapes.12,13 Negative pressure therapy was commenced for 6 days with a dressing change on day 3.
Measurements. All TCOM were performed while participants were in a relaxed supine position breathing room air. The skin site was prepped and light desquamation was achieved using a 70% isopropyl alcohol swab. Nurses trained in the technique placed three sensors heated to 44˚C around the ulcer in the recommended manner (ie, not over prominent bones or major vessels). The reference point measurement was taken from the second intercostal space. Resting transcutaneous oxygen pressure (TcPO2) was estimated using a transcutaneous oxygen monitor (Tina TCM 4, Radiometer, Copenhagen, Denmark) and data were recorded after the readings had been stabilized for 10 to 15 minutes. Recordings were taken on days 1 and 6 in the same environment and location for each patient. Tracings on picture diagrams and markings on the limbs were drawn to ensure accuracy in subsequently placing the sensors on the same location at the second visit.
Participants had a 24-hour phone line to call if assistance with the VAC device was needed. The VAC system was checked at each visit to ensure that the seal had been maintained at -125 mmHg throughout the study period.
The mean of the three TCOM around the ulcer for each patient was calculated. The data were entered into a Microsoft Excel database and statistically analyzed using R software (R Foundation for Statistical Computing, Vienna, Austria.) Differences in means were compared with the paired Student’s t-test; significance was determined at P < 0.05.
Seventeen participants (5 men and 9 women) were recruited, of whom three did not complete the trial and were excluded from the data analysis. Two of the patients did not cope with the VAC equipment (pump and the tubing) and the other participant withdrew on the second day due to significant pain from the ulcer. The median age was 73 years (range 49–85). Sixteen participants were nonsmokers and one was an ex-smoker. One patient had undergone previous hyperbaric oxygen therapy (HBOT) for their ulcer. Five patients had moderate LDS. There were no complications encountered with the TCOM. One patient developed contact dermatitis from the sealing drape on day 6.
1. Browse NL, Burnand KG. The cause of venous ulceration. Lancet. 1982;2(8292):243–245.
2. Coleridge Smith PD, Thomas P, Scurr JH, Dormandy JA. Causes of venous ulceration: a new hypothesis? Br Med J (Clin Red Ed). 1988;296(6638):1726–1727.
3. Hunt TK. The physiology of wound healing. Ann Emerg Med. 1988;17(12):1265–1273.
4. Robson MC. Disturbances of wound healing. Ann Emerg Med. 1988;17(12):1274–1278.
5. Smart D, Bennett M, Mitchell S. Transcutaneous oximetry, problem wounds and hyperbaric oxygen therapy. Diving Hyperb Med. 2006;36(2):72–86.
6. Messmer K, ed. Microcirculation in Chronic Venous Insufficiency; vol 23. Basel, Switzerland: Karger; 1999.
7. Morykwas MJ, Argenta LC, Shelton-Brown EI, McGuirt W. Vacuum-assisted closure: a new method for wound closure and treatment: animal studies and basic foundation. Ann Plast Surg. 1997;38(6):553–562.
8. Fabian TS, Kaufman HJ, Lett ED, et al. The evaluation of subatmospheric pressure and hyperbaric oxygen in ischemic full-thickness wound healing. Am Surg. 2000;66(12):1136–1143.
9. Chen SZ, Li J, Li XY, Xu LS. Effects of vacuum-assisted closure on wound microcirculation: an experimental study. Asian J Surg. 2005;28(3):211–217.
10. Wackenfors A, Sjögren J, Gustafsson R, Algotsson L, Ingemansson R, Malmsjö M. Effects of vacuum-assisted closure therapy on inguinal wound edge microvascular blood flow. Wound Repair Regen. 2004;12(6):600–606.
11. Eklöf B, Rutherford RB, Bergan JJ, et al. Revision of the CEAP classification for chronic venous disorders: consensus statement. J Vasc Surg. 2004;40(6):1248–1252.
12. Blair SD, Wright DD, Backhouse CM, Riddle E, McCollum CN. Sustained compression and healing of chronic venous ulcers. BMJ. 1988;297(6657):1159–1161.
13. Khashram M, Huggan P, Ikram R, Chambers S, Roake JA, Lewis DR. Effect of TNP on the microbiology of venous ulcers: a pilot study. J Wound Care. 2009;18(4):164–167.
14. Lorée S, Dompmartin A, Penven K, Harel D, Leroy D. Is vacuum assisted closure a valid technique for debriding chronic leg ulcers? J Wound Care. 2004;13(6):249–252.
15. Sheffield PJ. Measuring tissue oxygen tension: a review. Undersea Hyperb Med. 1998;25(3):179–188.
16. Jünger M, Steins A, Hahn M, Häfner HM. Microcirculatory dysfunction in chronic venous insufficiency (CVI). Microcirculation. 2000;7(6 Pt 2):S3–S12.
17. Cina C, Katsamouris A, Megerman J, et al. Utility of transcutaneous oxygen tension measurements in peripheral arterial occlusive disease. J Vasc Surg. 1984;1(2):362–371.
18. Byrne P, Naughton PM, O’Higgins NJ. Transcutaneous oxygen tension (PtcO2) in the lower limbs in venous disease. Br J Surg. 1984;71(12):990.
19. Clyne CA, Ramsden WH, Chant AD, Webster JH. Oxygen tension on the skin of the gaiter area of limbs with venous disease. Br J Surg. 1985;72(8):644–647.
20. Moosa HH, Falanga V, Steed DL, et al. Oxygen diffusion in chronic venous ulceration. J Cardiovasc Surg (Torino). 1987;28(4):464–467.
21. Nemeth AJ, Eaglstein WH, Falanga V. Clinical parameters and transcutaneous oxygen measurements for the prognosis of venous ulcers. J Am Acad Dermatol. 1989;20(2 Pt 1):186–190.
22. Dowd GS. Predicting stump healing following amputation for peripheral vascular disease using the transcutaneous oxygen monitor. Ann R Coll Surg Engl. 1987;69(1):31–35.
23. Hopf HW. Development of subcutaneous wound oxygen measurement in humans: contributions of Thomas K. Hunt, MD. Wound Repair Regen. 2003;11(6):424–430.
24. Padberg FT Jr, Back TL, Hart LC, Franco CD. Comparison of heated-probe laser Doppler and transcutaneous oxygen measurements for predicting outcome of ischemic wounds. J Cardiovasc Surg. 1992;33(6):715–722.
25. Stacey MC, Burnand KG, Layer GT, Pattison M. Transcutaneous oxygen tensions in assessing the treatment of healed venous ulcers. Br J Surg. 1990;77(9):1050–1054.
26. Christenson JT. Postthrombotic or non-postthrombotic severe venous insufficiency: impact of removal of superficial venous reflux with or without subcutaneous fasciotomy. J Vasc Surg. 2007;46(2):316–321.
27. Kolari PJ, Pekanmäki K. Effects of intermittent compression treatment on skin perfusion and oxygenation in lower legs with venous ulcers. Vasa. 1987;16(4):312–317.