Modern wound care for the poor: a randomized clinical trial comparing the vacuum system with conventional saline-soaked gauze dressings

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1 The American Journal of Surgery (2010) 199, Clinical Surgery-International Modern wound care for the poor: a randomized clinical trial comparing the vacuum system with conventional saline-soaked gauze dressings Daniel Perez, M.D. a,b, *, Matthias Bramkamp, M.D. c, Chauvet Exe, M.D. a, Christian von Ruden, M.D. d, Anna Ziegler, M.D. a,e a Department of General Surgery, Hôpital Albert Schweitzer, Deschapelles, Haiti; b Department of General Surgery, General Hospital Zurich-Triemli, Birmensdorfstrasse 497, 8063 Switzerland; c Department of Internal Medicine, University Hospital of Zurich, Switzerland; d Department of Trauma Surgery, University Hospital of Zurich, Switzerland; e Department of Paediatrics, University Children s Hospital of Zurich, Switzerland KEYWORDS: Wound care; Vaccuum dressing system Abstract BACKGROUND: A clinical randomized trial was performed to determine whether a simple homemade wound vacuum-dressing system (HM-VAC) is a feasible alternative to the use of conventional saline-soaked gauze dressings (WET) for the treatment of complex wounds in a resource-poor hospital. METHODS: Forty patients were analyzed to compare the HM-VAC and the WET dressings. The HM-VAC was assembled with tools available in most operating room worldwide. The primary outcome measure was the time of complete wound healing. Additionally, the costs of both methods were calculated. RESULTS: The time required to achieve complete healing was 16 days in the HM-VAC group compared with 25 days in the WET group (P.013). The HM-VAC costs US $360 per case, and the WET technique costs US $271 per case (P.008). CONCLUSIONS: The HM-VAC should be considered in underdeveloped countries to provide modern management for complex wounds because healing is significantly faster compared with conventional wound care. Although the HM-VAC is more costly than the conventional approach, it is probably affordable for most resource-poor hospitals Elsevier Inc. All rights reserved. The vacuum-assisted closure system (VAC) was introduced in 1997 by Argenta and Morykwas for the management of difficult-to-treat wounds, and many applications of this negative pressure technique have been reported since then. 1 4 The VAC has been shown to enhance granulation * Corresponding author: Tel.: ; fax: address: danielperezch@yahoo.com Manuscript received June 21, 2008; revised manuscript December 17, 2008 formation and wound closure in comparison with other dressing techniques for acute and chronic wounds. 2,5,6 The positive impact on wound healing and the improved patient comfort afforded by the VAC have resulted in a wide increase in the popularity of this new technique in the Western world. 2,5 7 The VAC treatment would also be ideal for the management of severe wounds often encountered by doctors in countries that, 8 because of their low socioeconomic status, have been defined by the United Nations as less- and least-developed countries (LDCs). 9 However, commercial devices are either not available or prohibitively /$ - see front matter 2010 Elsevier Inc. All rights reserved. doi: /j.amjsurg

2 D. Perez et al. Homemade VAC for underdeveloped countries 15 consecutively. Each patient had a single wound at the time at which he/she was included in the study. Patients entered the study when the decision to perform surgical debridement was made. Patients were randomized by a sealed envelope to receive treatment with either WET dressings or the HM-VAC technique. Patients with associated bony injuries or vascular ulcers were excluded from the study. Dressing Techniques HM-VAC dressing Figure 1 The sponge of a single-use povidone-iodine hand scrub brush (E-Z Scrub 205; Becton Dickinson, Franklin Lakes, NJ) was used as the principal component of the HM-VAC. expensive for most patients in resource-poor regions. In these countries, most surgeons apply the conventional daily dressings of saline.9%-soaked gauzes (WET) and perform frequent surgical debridements to enhance wound healing. Although this technique has proven to be effective, 10 recent studies comparing the results obtained when applying conventional dressings with those obtained when using the commercial VAC (Kinetic Concepts, Inc, San Antonio, TX) showed wound healing to be improved under subatmospheric pressure. 11,12 Although there now is an increasing amount of evidence that the VAC treatment is superior to traditional wound-management strategies, there are no data reporting the use of this technique in any LDCs. Even though the VAC is claimed to be a cost-effective treatment, 11,13 the commercially available devices are too expensive for most hospitals in LDCs. In contrast, a homemade VAC (HM-VAC) can be assembled with materials that are cheap and easily available. The HM-VAC would be of great value for treating severe wounds in underdeveloped parts of the world. To investigate the feasibility and the clinical results of this technique, we compared wound management using the HM-VAC with the conventional WET dressing technique in a clinical randomized trial performed at the Albert Schweitzer Hospital in Deschapelles, Haiti. After radical surgical debridement, the sterile sponge of a single use povidone-iodine hand scrub brush (E-Z Scrub 205; Becton Dickinson, Franklin Lakes, NJ) (Fig. 1) was trimmed and shaped to make a close contact with all surfaces of the wound (Fig. 2). The number of sponges used for each dressing was recorded and controlled at the next dressing change to avoid the retention of sponge pieces. Multiple small holes were cut into a sterile suction drainage tube (5 mm 3.1 m, Argyle; Kendall, Chicopee, MA), which was placed on top of the sponge (Fig. 3). All holes of the suction drainage tube were in close contact with the sponge. The wound was covered with an adhesive drape (OpSite; Smith & Nephew, Inc, Largo, FL), which extended at least 2 cm beyond the wound margins onto intact and dry skin. The drape was carefully wrapped around the suction tube to avoid pressure leakage and attached to the skin with a stitch (silk 1.0) (Fig. 4). The tube was then connected to the fluid bottle of a conventional chest tube suction device with a continuous negative pressure of 100 mm Hg. The amount of fluid or blood drained by the HM-VAC was monitored every 30 minutes for the first 6 hours after the application of a new dressing or a dressing change. In case of hemorrhage (200 ml per 30 minutes), the surgeon on call was informed. Methods Patients A detailed written consent form was signed by each patient or his/her guardian by signature or fingerprint before surgery. The study design was approved by the ethical board of the Albert Schweitzer Hospital, Deschapelles, Haiti. From January 2007 to June 2007, 49 patients were recruited Figure 2 The sponge was cut into pieces to make a close contact with all surfaces of the wound.

3 16 The American Journal of Surgery, Vol 199, No 1, January 2010 Table 1 Wound score of the granulation tissue Figure 3 Multiple small holes were cut into a sterile suction drainage tube (5 mm 3.1 m; Argyle, Kendall, Chicopee, MA), which was then placed on top of the sponge. All holes of the suction drainage tube were in close contact with the sponge. From 6 hours onward, the checkups were performed every 2 hours. Dressings were changed every 4 days under regional or general anesthesia. WET dressing The WET technique consisted of daily bedside changes of gauze dressings soaked with sterile.9% saline. In the event of persistent infection or necrotic wound areas, a surgical debridement was performed under regional or general anesthesia in the operating room. Figure 4 The HM-VAC was sealed with an adhesive drape (OpSite; Smith & Nephew, Inc, Largo, FL) that extended at least 2 cm beyond the wound margins. The drape was carefully wrapped around the suction tube to avoid pressure leakage and attached to the skin. Characteristics Granulation None 0 One quarter of wound area 1 One half of wound area 2 Two thirds of wound area 3 Complete wound area 4 Color Pale 0 Pink 1 Bright red 2 Consistency Spongy 0 Solid 1 Maximum Total score 7 Observations Points The primary endpoint determined was the duration of wound healing (in days) until wound closure or split-skin grafting was possible. The outcome of the wound healing with the HM-VAC and with the WET dressing was analyzed during the course of the treatment and 30 days after successful wound closure. The wounds that did not require skin grafting were judged to be healed if there were no local signs of redness, heat, edema, discharge, or wound dehiscence and in the absence of fever. If all these indicators were negative, the wound was considered to have healed completely. The wound healing was assessed in accordance with previously published criteria; 14,15 however, we did not calculate a wound-healing score. The etiology of the wounds was assessed, and the severity of the chronic wounds was scored based on the granulation, color, and consistency of the granulation tissue (Tables 1 and 2). 16 After wound conditioning, the wounds were re-evaluated using the wound score, 16 and split-skin grafting was performed in wounds scoring 5. Demographic data, the localization and surface area of the wound, comorbidities, and the number of operations performed until wound closure were recorded. The body mass index (kg/m 2 ) was assessed as an indirect parameter for malnutrition. To assess the wound surface (Table 2), the area of the wound was copied on a sheet of paper. The area drawn on the paper was cut and weighed to calculate the area surface according to the paper density (80 mg/m 2 ). The total average cost per patient was calculated including the daily fee for hospital stay (200 Haitian Gourdes/d US $5/d), the charge for wound debridement and dressing change in the operation room (Haitian Gourdes 1,100/operation US $27.5/operation) and the material costs for the dressings. This sum does not reflect the true cost but rather the revenues from the patients payment. The HM-VAC material included the sterile hand scrub sponge, the suction drainage tube, and the adhesive drape per square centimeter. The cost calculation for the HM-VAC did not take charges

4 D. Perez et al. Homemade VAC for underdeveloped countries 17 Table 2 Patient and wound characteristics Treatment Randomized: n 49 VAC (n 20)* WET (n 20)* P Sex (M/F) 12/8 9/ Age 48.6 (37 61) 44.1 (32 54).192 Wound surface (cm 2 ) 44.9 (9 189) 39.8 (4 193).082 Body mass index (kg/m 2 ) 17.5 ( ) 19.3 ( ).129 Diabetes mellitus II 7 (35) 6 (30).420 Smoking 3 (15) 6 (30).125 Antibiotics 7 (35) 16 (80).005 Other drugs 4 (20) 8 (40).150 Acute wounds 11 (55) 14 (70).257 Fasciitis 4 (20) 3 (15) Fournier gangrene 1 0 Leg 3 2 Forearm 0 1 Postoperative infection 3 (15) 4 (20).423 Abdominal wound 2 2 Cervical wound 1 0 Inguinal hernia repair 0 2 Infected wound after trauma to extremities 4 (20) 7 (35).126 Gunshot wound 1 3 Stab wound 1 4 Accident 2 0 Chronic wounds Venous leg ulcer 9 (45) 6 (30).153 Diabetic foot ulcer 6 (30) 2 (10).103 Chronic wound score 16 3 (15) 4 (20).703 Lost to follow-up: n (2 5) 2.7 (1 3).198 Death 1 (5) 1 (5).991 Unknown 2 (10) 5 (25).540 NS not significant. *Data are median (minimum maximum) or number and percent. 1 selective blocker, cimetidine, insulin, phenytoin. Albendazol, non-and 1 selective blockers (n,4 cimetidin, insulin (n,2). Chi-square test, paired t test, or Fisher exact test as appropriate. for using electrical power for the suction device into account. HM-VAC dressings were changed every 4 days. The WET dressing costs included the sterile gauzes (15 cm 15 cm; Protec, El Paso, TX) and the sterile saline solution (100 ml; B. Braun Medical, Inc, Santo Domingo, Dominican Republic). Statistical analysis The Pearson chi-square test or Fisher exact test was used to compare observed proportions of categoric data in the HM-VAC and WET treatment groups. The outcome of wound healing (ie, days to wound closure or skin graft) in each group was assessed by the paired t test. All statistical calculations were performed with SPSS 11 software (SPSS, Chicago, IL). The sample size (40 cases, 20 in each group) was calculated on the basis of a t test for a difference of wound healing duration between both groups assuming a difference of 10 with a power of.8 and allowing a type I error of 5%. A result was considered statistically significant with P.05. Results The time period that elapsed between initial debridement and successful wound closure or split-skin grafting was significantly (P.013) shorter in the HM-VAC group than in the WET group (Table 3). The etiology of the wounds was equally distributed in both groups as shown in Table 2. Patients in the HM-VAC group required 6.8 (95% confidence interval [CI], ) operations under regional or general anesthesia until definitive wound closure compared with 4.0 (95% CI, ) operations in the WET group (P.038). The number of dressing changes was significantly higher in the WET group (P.001) compared with the HM-VAC group (Table 3). Of the initially randomized 49 patients, 9 individuals (VAC: n 5; WET: n 4) did not complete the follow-up because of death or unknown

5 18 The American Journal of Surgery, Vol 199, No 1, January 2010 Table 3 Wound healing duration, technique of wound closure, and outcome 30 days after closure Wound closure VAC WET Test P Duration (d) (range) 16.3 ( ) 25.4 ( ) t test.013 Dressings* 6.1 ( ) 31.3 ( ) t test.001 Technique (%) Direct 13 (75) 9 (45) 2 test.091 Skin graft 7 (35) 11 (55) Outcome (%) Healed 18 (90) 19 (95) 2 test.302 *Number of dressing changes as median and 95% confidence interval. Numbers and corresponding percent. Direct surgical closure after wound conditioning. Follow-up examination 30 days after wound closure or split-skin grafting. causes as specified in Table 2. Patients characteristics and details on their type of wound in the 2 treatment arms are presented in Table 2. Although a tendency for a larger wound surface was observed in the HM-VAC group (P.082), the application of antibiotics was higher in the WET group (P.005). The baseline factors conductive for poor wound healing (ie, age, surface area, localization, etiology, smoking, and nutritional status) 17 and the clinical and demographic characteristics were comparable in both groups (Table 2). The median body mass index in both groups ranged between 17.5 kg/m 2 and 19.3 kg/m 2 indicating borderline nutritional status. Eight vacuum dressings had to be removed after a median duration of 1.3 days (95% CI, days) after a previous dressing change. Reasons for early unscheduled dressing changes included postoperative hemorrhage during the first 12 hours after the dressing change (in 4 cases), massive purulent secretion through the dressing and sepsis (in 3 cases), and a loss of negative pressure at the tube/dressing connecting site. The total average cost for the hospital stay, the surgery and the dressing material is shown in Table 4. Table 4 Total treatment cost per patient Total cost per case (USD)* VAC (n 20) WET (n 20) P# Hospital stay 83 (72 97) 121 ( ).008 Surgery 188 ( ) 105 (97 119).0001 Dressing material 81 (62 101) 50 (23 58).021 Total 360 ( ) 271 ( ).008 Chi-square test or paired t test as appropriate. *Currency exchange rate Haitian Gourdes (G) and United States Dollars (USD): US $ Haitian Gourdes. Cost for hospital stay calculated as average on the basis of a G 200/d fee (US $5/d). Median and 95% confidence interval. Cost for surgery calculated as average on the basis of G 1,100/ operation (US $27.5/operation). Median and 95% confidence interval. Exact material cost presented as median and 95% confidence Interval. #Chi-square test or paired t test as appropriate. Comments The results of the present randomized clinical study suggest that wound management with the HM-VAC is feasible in a LDC inpatient facility with excellent short-term results. The greatest benefit of the HM-VAC is the 41% reduction in the median wound-healing time in contrast to the WET dressing technique (Table 3). The materials required to assemble the HM-VAC are readily available, and the technique can be rapidly adopted by local surgeons. A recent randomized clinical trial comparing the use of the commercial VAC device with conventional woundcare techniques for the treatment of chronic leg ulcers reported that the VAC management resulted in significant advantages concerning wound healing. 13 We considered that the HM-VAC we describe here might also provide a similar beneficial effect in the treatment of acute and chronic wounds. In fact, our study confirmed previous clinical results obtained with the commercial VAC device. The HM-VAC system permitted the constant application of negative pressure and sustained drainage, which are 2 of the main properties responsible for enhanced wound healing. 18 Previous experimental studies have shown that shear forces exerted by vacuum on the wound bed lead to tissue proliferation with an increased rate of mitosis and overexpression of tissue growth factors. 5 The phenomenon of cellular proliferation under shear forces has been made use of in tissue expansion in plastic surgery. 19 In our opinion, the larger number of primary wound closures in the vacuum group might be related to enhanced tissue proliferation and wound contracture. Philbeck et al 20 reported that the commercial VAC therapy is more cost-effective than using traditional dressings. The reduction in cost in this study was mainly because of the shorter hospitalization time required. 20 The cost analysis of our study has not been performed in a comprehensive manner. It was not possible to assess the direct intraoperative expenses including material costs, staff expenses, and costs for the anesthesia because these data could not be traced from the hospital administration. Therefore, we calculated an overall average cost per patient including the

6 D. Perez et al. Homemade VAC for underdeveloped countries charges for hospital stay, surgery, and dressing material while being aware of the shortcomings of our cost analysis. Despite a significantly reduced duration of hospital stay in the HM-VAC group, the total average cost per patient was clearly higher with this treatment. Significantly higher operative costs and higher costs for dressing material were observed with the HM-VAC treatment compared with the WET management. Nevertheless, costs remained within a range that is probably affordable for most patients or charitable organizations in underdeveloped parts of the world. Although we have achieved good short-term results with the HM-VAC, long-term results are not yet available. We have not encountered any problems in using our device. However, there is some concern that large or oozing wounds could bleed excessively at the time of dressing application into the suction canister, which, unlike commercial devices, does not have a volume level cutoff. On account of this limitation, we urge caution in using the HM-VAC for the treatment of large wounds that are likely to bleed excessively. Another source of uncertainty is the placement of a povidone-iodine soaked sterile hand scrub sponge placed directly on top of the wound because some concerns about the toxicity of povidone-iodine on fibroblasts and keratinocytes have been reported recently. 21 However, this issue remains controversial because recent clinical studies have shown that the application of povidone-iodine soaked dressings even enhanced the healing of chronic leg ulcers in comparison to the use of silver sulfadiazine (2% 7%) or chlorhexidine digluconate (1% 5%). 22,23 The interpretation of our results is complicated by the diversity of the causes of the wounds analyzed in the present study. Nevertheless, we decided to treat both acute and chronic wounds with the HM-VAC to improve the assessment, the practicability, and the handling of this new technique in a LCD hospital setting. Statistical analysis showed that there was no significant difference in the causes of the wounds treated in each of both groups. Additional limitations that might compromise the validity of our interpretations are factors influencing wound healing that go beyond the effects stemming from the dressing technique itself (eg, nutritional status or associated comorbidities). The wound healing results were judged by an unblinded observer, which has to be regarded as a possible source of bias. Some authorities might be concerned about the quality assurance of wound treatment if surgeons assemble their own HM-VAC devices from off-the-shelf ingredients. The surgeon might also feel more comfortable using a commercial VAC because it is guaranteed to meet a certain standard of quality by the supplier. But is this really necessary in an LDC? Quality assurance is indeed important in providing a satisfactory level of production quality for a given device. However, although international quality-assurance standards for health devices are high, they are unlikely to justify or account for the high price of reputable devices such as the VAC. The outcome of the trial presented here suggests that an adequate quality of treatment can be obtained with the HM-VAC as well as a clinical performance superior to that achieved with the traditional WET dressing. The surgeon must assume full responsibility for the application of the HM-VAC. However, this is nothing exceptional because surgeons are generally responsible for the proper use of any device in the treatment of their patients. The VAC has revolutionized the wound-management approach for difficult-to-treat wounds in the Western world. Unfortunately, this development has not yet taken place in underdeveloped parts of the world, most likely because of the extremely high costs of commercial devices. The commercial VAC system is one of many examples that show how patients in LDCs remain underprivileged not only economically but also concerning the quality of medical care. Surgeons and other medical staff working in underprivileged areas should be encouraged to search for treatment options to provide widespread affordable and up-todate care to their patients. The application of the HM-VAC in the developing world warrants excellent wound care and acceptable costs. However, long-term clinical results with this new device are necessary, even though this may not always be easy in countries in which patients depart for their villages once they are cured. Acknowledgments We thank Paul Ziegler, Ph.D., Department of Biology from the University of Bayreuth, Germany for proofreading the manuscript. References 1. Argenta LC, Morykwas MJ. Vacuum-assisted closure: a new method for wound control and treatment: clinical experience. Ann Plast Surg 1997;38: Argenta LC, Morykwas MJ, Marks MW, et al. Vacuum-assisted closure: state of clinic art. Plast Reconstr Surg 2006;117(Suppl):127S 42S. 3. Venturi ML, Attinger CE, Mesbahi AN, et al. Mechanisms and clinical applications of the vacuum-assisted closure (VAC) device: a review. Am J Clin Dermatol 2005;6: Perez D, Wildi S, Clavien PA. The use of an abdominal vacuumdressing system in the management of abdominal wound complications. Adv Surg 2007;41: Morykwas MJ, Simpson J, Punger K, et al. Vacuum-assisted closure: state of basic research and physiologic foundation. Plast Reconstr Surg 2006;117(Suppl):121S 6S. 6. Perez D, Wildi S, Demartines N, et al. Prospective evaluation of vacuum-assisted closure in abdominal compartment syndrome and severe abdominal sepsis. J Am Coll Surg 2007;205: Banwell PE, Musgrave M. Topical negative pressure therapy: mechanisms and indications. Int Wound J 2004;1: Fu X, Wang Z, Sheng Z. Advances in wound healing research in China: from antiquity to the present. Wound Repair Regen 2001;9:

7 20 The American Journal of Surgery, Vol 199, No 1, January Yearbook of the United Nations 2004: A More Secure World Our Shared Responsibility. United Nations Publications, Department of Public Information; Jensen JL, Seeley J, Gillin B. Diabetic foot ulcerations. A controlled, randomized comparison of two moist wound healing protocols: Carrasyn hydrogel wound dressing and wet-to-moist saline gauze. Adv Wound Care 1998;11(Suppl): Braakenburg A, Obdeijn MC, Feitz R, et al. The clinical efficacy and cost effectiveness of the vacuum-assisted closure technique in the management of acute and chronic wounds: a randomized controlled trial. Plast Reconstr Surg 2006;118: Moues CM, Vos MC, van den Bemd GJ, et al. Bacterial load in relation to vacuum-assisted closure wound therapy: a prospective randomized trial. Wound Repair Regen 2004;12: Vuerstaek JD, Vainas T, Wuite J, et al. State-of-the-art treatment of chronic leg ulcers: A randomized controlled trial comparing vacuumassisted closure (V.A.C.) with modern wound dressings. J Vasc Surg 2006;44: Cooper D. Human wound assessment: status report and implications for the clinician. AACN Clin Issues 1990;1: Sterling C. Methods of wound assessment documentation: a study. Nurs Stand 1996;11: Schmidt WD, Liebold K, Fassler D, et al. Contact-free spectroscopy of leg ulcers: principle, technique, and calculation of spectroscopic wound scores. J Invest Dermatol 2001;116: Bowler PG. Wound pathophysiology, infection and therapeutic options. Ann Med 2002;34: Mendonca DA, Papini R, Price PE. Negative-pressure wound therapy: a snapshot of the evidence. Int Wound J 2006;3: Johnson TM, Lowe L, Brown MD, et al. Histology and Physiology of tissue expansion. J Dermatol Surg Oncol 1993;19: Philbeck TE Jr, Whittington KT, Millsap MH, et al. The clinical and cost effectiveness of externally applied negative pressure wound therapy in the treatment of wounds in home healthcare Medicare patients. Ostomy Wound Manage 1999;45: Wilson JR, Mills JG, Prather ID, et al. A toxicity index of skin and wound cleansers used on in vitro fibroblasts and keratinocytes. Adv Skin Wound Care 2005;18: Fumal I, Braham C, Paquet P, et al. The beneficial toxicity paradox of antimicrobials in leg ulcer healing impaired by a polymicrobial flora: a proof-of-concept study. Dermatology 2002;204(Suppl 1): Balin AK, Pratt L. Dilute povidone-iodine solutions inhibit human skin fibroblast growth. Dermatol Surg 2002;28:210 4.