Interim analysis of a prospective, randomized trial of vacuum-assisted closure versus the healthpoint system in the management of pressure ulcers. State-of-the-art treatment of chronic leg ulcers: A randomized controlled trial comparing vacuum-assisted closure (V.A.C.) with modern wound dressings. A prospective randomized evaluation of negative-pressure wound dressings for diabetic foot wounds. Bacterial load in relation to vacuum-assisted closure wound therapy: a prospective randomized trial. Vacuum-assisted closure versus saline-moistened gauze in the healing of postoperative diabetic foot wounds. Vacuum-assisted wound closure for cheaper and more comfortable healing of pressure sores: a prospective study.
Twenty-eight patients with 41 full-thickness decubitus ulcers were randomized to compare the Vacuum-Assisted Closure device (VAC) with the Healthpoint System (HP) of wound gel products in promoting ulcer healing. A total of 22 patients with 35 full-thickness ulcers completed the 6-week trial of treatment, during which time 2 patients (10%) in the VAC group (N =20) and 2 patients (13%) in the HP group (N = 15) healed completely. The mean percent reduction in ulcer volume was 42.1% with HP and 51.8% with VAC (p = 0.46). The mean number of PMNs and lymphocytes per high-power field decreased in the VAC group and increased in the HP group (p = 0.13, p = 0.41 respectively). The mean number of capillaries per high-power field was greater in the VAC group (p = 0.75). There were 15 cases of biopsy-proven osteomyelitis underlying the ulcers; three (37.5%) improved with VAC and none improved with HP (p = 0.25). VAC promotes an increased rate of wound healing and favorable histological changes in soft tissue and bone compared with HP. Current treatment modalities for chronic leg ulcers are time consuming, expensive, and only moderately successful. Recent data suggest that creating a subatmospheric pressure by vacuum-assisted closure (V.A.C., KCI Concepts, San Antonio, Texas) therapy supports the wound healing process.
                The efficacy of vacuum-assisted closure in the treatment of chronic leg ulcers was prospectively studied in a randomized controlled trial in which 60 hospitalized patients with chronic leg ulcers were randomly assigned to either treatment by V.A.C. or therapy with conventional wound care techniques. The primary outcome measure was the time to complete healing (days). Statistical analysis was performed on the intention-to-treat basis.
                The median time to complete healing was 29 days (95% confidence interval [CI], 25.5 to 32.5) in the V.A.C. group compared with 45 days (95% CI, 36.2 to 53.8) in the control group (P = .0001). Further, wound bed preparation during V.A.C. therapy was also significantly shorter at 7 days (95% CI 5.7 to 8.3) than during conventional wound care at 17 days (95% CI, 10 to 24, P = .005). The costs of conventional wound care were higher than those of V.A.C. Both groups showed a significant increase in quality of life at the end of therapy and a significant decrease in pain scores at the end of follow-up.
                V.A.C. therapy should be considered as the treatment of choice for chronic leg ulcers owing to its significant advantages in the time to complete healing and wound bed preparation time compared with conventional wound care. Particularly during the preparation stage, V.A.C. therapy appears to be superior to conventional wound care techniques. Optimal treatment for large diabetic foot wounds is ill defined. The purpose of this study was to compare the rate of wound healing with the Vacuum Assisted Closure device trade mark (VAC) to conventional moist dressings in the treatment of large diabetic foot wounds. Diabetics with significant soft tissue defects of the foot were considered for enrollment. Patients were randomized to receive either moist gauze dressings or VAC treatments for 2 weeks, after which they were treated with the alternative dressing for an additional 2 weeks. Wounds were photographed weekly and wound dimensions calculated in a blinded fashion with spatial analysis software. Percent change in wound dimensions were calculated and compared for each weekly assessment and over 2 weeks of therapy with each dressing type. Ten patients were enrolled in the trial, but two were lost to follow-up and two were withdrawn. Complete data were available for analysis on seven wounds in six patients. Average length, width, and depth of the wounds at initiation of the trial was 7.7, 3.5, and 3.1 cm, respectively. Only the wound depth was significantly decreased over the weeks of the trial to 1.2 cm ( p < 0.05). VAC dressings decreased the wound volume and depth significantly more than moist gauze dressings (59% vs. 0% and 49% vs. 8%, respectively). VAC dressings were associated with a decrease in all wound dimensions while wound length and width increased with moist dressings. In summary, over the first several weeks of therapy, VAC dressings decreased wound depth and volume more effectively than moist gauze dressings. Negative-pressure wound treatment may accelerate closure of large foot wounds in the diabetic patient. Vacuum-assisted closure has become a new technique in the challenging management of contaminated, acute, and chronic wounds. Although promising clinical results have been described, scientific proof to substantiate the mechanism of action of this therapy is scarce. In the present study, we examined whether the positive effect on wound healing found in vacuum-assisted closure-treated wounds could be explained by an effect on the bacterial load. Fifty-four patients who needed open wound management before surgical closure were included in this study. Wounds were randomized to either vacuum-assisted closure therapy (n= 29) or treatment by conventional moist gauze therapy (n= 25). Healing was characterized by development of a clean granulating wound bed ("ready for surgical therapy") and reduction of wound surface area. To quantify bacterial load, biopsies were collected. No significant difference was found in time needed to reach "ready for surgical therapy" comparing both therapies. Wound surface area reduction was significantly larger in vacuum-assisted closure-treated wounds: 3.8 +/- 0.5 percent/day (mean +/- SEM) compared to conventional-treated wounds (1.7 +/- 0.6 percent/day; p < 0.05). The total quantitative bacterial load was generally stable in both therapies. However, nonfermentative gram negative bacilli showed a significant decrease in vacuum-assisted closure-treated wounds (p < 0.05), whereas Staphylococcus aureus showed a significant increase in vacuum-assisted closure-treated wounds (p < 0.05). In conclusion, this study shows a positive effect of vacuum-assisted closure therapy on wound healing, expressed as a significant reduction of wound surface area. However, this could not be explained by a significant quantitative reduction of the bacterial load. Diabetic foot wounds present a great challenge to wound care practitioners. The objective of this pilot study was to determine whether vacuum-assisted closure (V.A.C.) therapy would afford quicker wound resolution as compared to saline-moistened gauze in the treatment of postoperative diabetic foot wounds. Ten patients were randomized into either the experimental V.A.C. group or control saline gauze group. Included in the study were diabetic patients 18 to 75 years of age who had a nonhealing foot ulceration. Excluded were those patients with venous disease, coagulopathy, or those who had active infections not resolved by initial surgical debridement. All foot ulcers were surgically debrided prior to initiation of V.A.C. or gauze treatment. In the experimental group, V.A.C. dressings were applied in accordance with manufacturer's protocol for chronic wounds and changed every 48 hours. In the control group, saline gauze dressings were applied at the time of surgical debridement and changed twice a day thereafter. Measurements and photos were obtained to document wound progress. Main outcome measures included: 1) time to satisfactory healing (calculated from date of initial debridement to date of definitive closure, and 2) change in wound surface area (calculated from initial wound tracing to final tracing). Satisfactory healing in the V.A.C. group was achieved in 22.8 (+/- 17.4) days, compared to 42.8 (+/- 32.5) days in the control group. Surface area changes of 28.4% (+/- 24.3) average decrease in wound size in the V.A.C. group, compared to a 9.5% (+/- 16.9) average increase in the control group during measurement period. Pressure sores are a common complication of patients with spinal injuries. The vacuum-assisted closure technique is widely used to induce and promote wound healing. We tested our clinical impression that pressure sores healed faster with vacuum-assisted closure, and compared it with the traditional wet-to-dry/wet-to-wet technique with gauze soaked in Ringer's solution changed three times a day. Consecutive patients with pressure sores were entered into the study. Two randomised groups of 11 patients each with pressure sores of the pelvic region were included. We found no difference in time to reach 50% of the initial wound volume between the two methods. The vacuum-assisted group took a mean (SD) of 27 (10) days and the traditional group 28 (7) days. The two methods were equally effective in forming granulation tissue, so one can profit from the other advantages of the vacuum-assisted treatment (reduced costs and improved comfort) knowing that the effect on the formation of granulation tissue is as good as with the traditional treatment.
Trials comparing TNP with alternative treatments for chronic wounds have methodological flaws and data do demonstrate a beneficial effect of TNP on wound healing however more, better quality research is needed.