Occlusive dressing

Abstract: Contoured wounds needing closure with skin grafts are often located in complex anatomic regions or are in unusual positions, which make conventional skin graft stabilization techniques cumbersome and ineffective. Often after 72 hours, a skin graft covered with a bolstered dressing has poor take secondary to shear stresses, as well as hematoma formation or serum collection, negating the effectiveness of the stabilizing dressing. The Food and Drug Administration has recently approved vacuum-assisted closure (V.A.C.), an innovative technique using negative pressure, for closure of chronic wounds. This reportedly leads to enhanced granulation tissue formation and consequently more rapid reepithelialization of wounds compared with conventional packing with saline-moistened gauze. Experimental studies have demonstrated increased oxygen tension, decreased bacterial counts, and increased granulation formation occurring under negative-pressure systems. Extending the use of this concept, we have coupled skin grafting with negative-pressure dressings for closure of large, complex open wounds. Our results indicate greater than 95% graft take in all patients in this study. This technique is extremely efficacious, with increased graft take due to total immobilization of the graft, thereby limiting shear forces, elimination of fluid collections, bridging of the graft, and decreased bacterial contamination. Moreover we have noted decreased edema in rotated muscle flaps, improved contour conformity, and shortened hospitalizations.

Abstract: 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.

Abstract: Maintaining a moist wound environment facilities the wound-healing process. The beneficial effects of a moist versus a dry wound environment include: prevention of tissue dehydration and cell death, accelerated angiogenesis, increased breakdown of dead tissue and fibrin, i.e., pericapillary fibrin cuffs, and potentiating the interaction of growth factors with their target cells. In addition, pain is significantly reduced when wounds are covered with an occlusive dressing. Concerns that moisture in wounds would increase the risk of clinical infection over traditional therapies are unfounded. The use of hydrocolloid occlusive dressings in maintaining a moist wound environment has proved to be a useful adjunct in facilitating wound healing.

Abstract: Context Use of a chlorhexidine gluconate–impregnated sponge (CHGIS) in intravascular catheter dressings may reduce catheter-related infections (CRIs). Changing catheter dressings every 3 days may be more frequent than necessary. Objective To assess superiority of CHGIS dressings regarding the rate of major CRIs (clinical sepsis with or without bloodstream infection) and noninferiority (less than 3% colonization-rate increase) of 7-day vs 3-day dressing changes. Design, Setting, and Patients Assessor-blind, 2 × 2 factorial, randomized controlled trial conducted from December 2006 through June 2008 and recruiting patients from 7 intensive care units in 3 university and 2 general hospitals in France. Patients were adults (>18 years) expected to require an arterial catheter, central-vein catheter, or both inserted for 48 hours or longer. Interventions Use of CHGIS vs standard dressings (controls). Scheduled change of unsoiled adherent dressings every 3 vs every 7 days, with immediate change of any soiled or leaking dressings. Main Outcome Measures Major CRIs for comparison of CHGIS vs control dressings; colonization rate for comparison of 3- vs 7-day dressing changes. Results Of 2095 eligible patients, 1636 (3778 catheters, 28 931 catheter-days) could be evaluated. The median duration of catheter insertion was 6 (interquartile range [IQR], 4-10) days. There was no interaction between the interventions. Use of CHGIS dressings decreased the rates of major CRIs (10/1953 [0.5%], 0.6 per 1000 catheter-days vs 19/1825 [1.1%], 1.4 per 1000 catheter-days; hazard ratio [HR], 0.39 [95% confidence interval {CI}, 0.17-0.93]; P = .03) and catheter-related bloodstream infections (6/1953 catheters, 0.40 per 1000 catheter-days vs 17/1825 catheters, 1.3 per 1000 catheter-days; HR, 0.24 [95% CI, 0.09-0.65]). Use of CHGIS dressings was not associated with greater resistance of bacteria in skin samples at catheter removal. Severe CHGIS-associated contact dermatitis occurred in 8 patients (5.3 per 1000 catheters). Use of CHGIS dressings prevented 1 major CRI per 117 catheters. Catheter colonization rates were 142 of 1657 catheters (7.8%) in the 3-day group (10.4 per 1000 catheter-days) and 168 of 1828 catheters (8.6%) in the 7-day group (11.0 per 1000 catheter-days), a mean absolute difference of 0.8% (95% CI, −1.78% to 2.15%) (HR, 0.99; 95% CI, 0.77-1.28), indicating noninferiority of 7-day changes. The median number of dressing changes per catheter was 4 (IQR, 3-6) in the 3-day group and 3 (IQR, 2-5) in the 7-day group (P Conclusions Use of CHGIS dressings with intravascular catheters in the intensive care unit reduced risk of infection even when background infection rates were low. Reducing the frequency of changing unsoiled adherent dressings from every 3 days to every 7 days modestly reduces the total number of dressing changes and appears safe. Trial Registration clinicaltrials.gov Identifier: NCT00417235