Hydrocolloid vs Gauze Dressings in Treating Pressure Ulcers: A Meta-Analysis of Randomized Controlled Trials

Objective. The aim of this meta-analysis was to evaluate the efficacy of a hydrocolloid dressing in the treatment of pressure ulcers compared with a traditional gauze dressing. Methods. Randomized controlled trials were identified by searching PubMed and Web of Science. Outcomes were complete wound healing rate and reduction in wound volume or surface area. Results. Seven studies with 302 patients (337 pressure ulcers) were included. Hydrocolloid dressings were associated with a statistically significant improvement of complete wound healing rate compared with gauze dressings (Odds ratio = 3.642, 95% Confidence Interval 1.104 to 12.012, z = 2.12, P = 0.034). Possible publication bias exists in this meta-analysis. Three studies also confirmed the hydrocolloid dressing was associated with a statistically significant reduction in wound volume compared with the gauze dressing. Conclusion. The existent evidence shows that a hydrocolloid dressing is more effective than a gauze dressing for pressure ulcer treatment. Accordingly, the authors suggest that in the treatment of pressure ulcers, traditional gauze dressings should be abandoned.

 In recent years, significant progress has been made in the prevention and treatment of pressure ulcers, however they remain a common problem for nurses. The overall prevalence rates and facility-acquired pressure ulcer rates were 13.5% and 6% in 2008, and 12.3% and 5% in 2009. In long-term acute care the overall prevalence rates were highest (22%), while in adult intensive care units (ICUs), the facility-acquired rates were highest (ranged 8.8% to 12.1%).¹ Pressure ulcers are painful, result in prolonged hospital stays, and may generate significant additional costs.

  Effective strategies to treat pressure ulcers are use of support surfaces, nutritional supplementation, and local wound care by wound dressings, biological agents, and adjunctive therapies.² While traditional gauze dressings are the most commonly used in the treatment of pressure ulcers, hydrocolloid dressings are also widely used. Although randomized controlled trials (RCTS) have assessed the efficacy of hydrocolloid dressings in the treatment of pressure ulcers compared with gauze dressings, the results have been inconsistent between studies.^3-4 The aim of this meta-analysis was to evaluate the efficacy of hydrocolloid dressings in the treatment of pressure ulcers compared with traditional gauze dressings.

A search of PubMed and Web of Science, from their inception to May 25, 2013, included the terms “hydrocolloid dressing,” “gauze dressing,” and “pressure ulcer.” The search detail in PubMed was hydrocolloid [TW] AND gauze [TW] AND “Pressure Ulcer” [MeSH]. In Web of Science citation database, the authors selected the Science Citation Index Expanded (SCI-EXPANDED) and Conference Proceedings Citation Index Science (CPCI-S) databases. The search detail used was as follows: TS = hydrocolloid AND Topic (TS) = gauze AND TS = “pressure ulcer.” The authors supplemented the searches by manually reviewing the references of all relevant studies. No language restrictions were applied on these searches.

  Study selection. The inclusion criteria included the following: only RCTs were included; patients had a stage I-IV pressure ulcer; hydrocolloid dressing vs gauze dressing was used in the treatment of pressure ulcers; complete wound healing rate and reduction in wound volume or surface area was achieved. Case reports, case series, single arm phase I trials, retrospective case-control studies, and phase II nonrandomized trials were excluded.

  Quality assessment. Study quality was evaluated using the Jadad scale which offers a score ranging from 1-5 based on the following parameters: randomization (2), double-blinding (2), and withdrawals/dropouts at follow-up (1). A final score of 1-2 is defined as low quality and 3-5 as high quality.⁵ Two reviewers independently assessed the quality of each included study, and disagreements were resolved by discussion.

  Data extraction. A standard form was used to extract data on first author, year of publication, country and setting in which the study was carried out, number of patients, age, pressure ulcer severity, duration of treatment, complete wound healing rate, and reduction in wound in 2 groups, respectively.

Statistical Analysis. Statistical heterogeneity was explored by inconsistency (I²) statistics; values of 0% to 30% represented minimal heterogeneity, 31% to 50% moderate heterogeneity, and greater than 50% substantial heterogeneity.⁶ If there was minimal heterogeneity, a fixed effects model was used for meta-analysis; otherwise, a random effect model based on the Der Simonian and Laird estimator was used.⁷ Summary odds ratio (OR) was calculated by taking a weighted average of individual study results. Two-sided P < 0.050 was considered statistically significant. Potential publication bias was tested by funnel graph. Analyses were all performed with Stata software, version 12.0 (Stata Corp, College Station, Texas).

Eligible studies and quality. Seven RCT studies^3-4,8-12 that met the inclusion criteria for meta-analysis were identified. Figure 1 shows the stages in identifying studies for inclusion in the review. Characteristics of the studies from the 7 articles included in meta-analyses are shown in Table 1. Two studies were conducted in the United States, while Iran, Denmark, Malaysia, Korea, and Sweden each contributed 1 study. Four studies reported data on long-term and home care; the other three studies reported data on hospital care. A total of 302 patients with 337 pressure ulcers were used in the pooled analyses. Of the 7 studies, the sample sizes ranged from 32 to 83; the patients’ age ranged from 18 to 100 years; the pressure ulcer severity ranged from stage I to stage IV; the duration of treatment ranged from 6 days to 12 weeks. The Jadad Scale of all included studies scored 2, which indicated low quality.

  Complete wound healing rate in hydrocolloid dressing vs gauze dressing. A total of 4 studies^8-11 provided sufficient data to analyze complete wound healing rate, which included 293 patients with 350 pressure ulcers. The complete wound healing rate in the hydrocolloid dressing group ranged from 22.9% to 88.9%, and in the gauze dressing group from 2.0% to 85.7%. There was substantial heterogeneity in 6 studies (I² = 6.66, P = 0.084). The summary OR of the complete wound healing rate in patients treated with hydrocolloid dressings compared with patients treated with gauze dressings was 3.642 (95% Confidence Interval [CI] 1.104 to 12.012, z = 2.12, P = 0.034) (Figure 2). Funnel plot showed asymmetry that indicated possible publication bias in this meta-analysis (Figure 3).

  Wound reduction in hydrocolloid dressing vs saline-gauze dressing. Matzen et al³ reported the relative volumes, based on the initial 100%, of hydrogel-treated wounds were significantly less (26 ± 20%, P < 0.02) than those of saline treated wounds (64 ± 16%) in the 12 weeks. Chang et al⁴ reported the hydrocolloid dressing experienced a mean 34% reduction from their baseline surface area measurement compared to a mean 9% increase by subjects assigned gauze dressings (P = 0.2318). Alm et al¹² reported, at week 6, the median remaining ulcer area, described as percentage of the initial ulcer area, was 0% in the hydrocolloid dressing group and 31% in the group treated with saline gauze (P = 0.016).

Table 2

 This meta-analysis found hydrocolloid dressings were more effective than gauze dressings for pressure ulcer treatment in the complete wound healing rate, with the OR 3.642 (95% CI 1.104 to 12.012). In the outcome of wound volume or surface area reduction, 2 included studies confirmed the hydrocolloid dressing was more effective than gauze dressings. Data of wound reduction wasn’t pooled because of different data type. Several characteristics of hydrocolloids are related to the treatment effectiveness. Hydrocolloid dressings that promote a moist wound environment produced better results than those that promote a dry wound environment, with an earlier onset of healing and better healing outcomes.¹³ Hydrocolloid dressings also promote granulation tissue¹⁴ and prevent infection in wounds,¹⁵ which is very important for pressure ulcer healing.

  Aside from pressure ulcer healing, some other advantages of hydrocolloid dressings were also found. Compared with gauze dressings, hydrocolloids were more effective with regard to the time to heal, the ease of handling of the dressing, the time needed for dressing changes, the dressing’s absorption capacity, and the pain during dressing changes.¹⁶ Hydrocolloid dressings also proved to be the most cost-effective. The cost of hydrocolloids was lower if the costs of materials and the cost of staff were taken into account and calculated on the basis of the length of time between, and the frequency of, dressing changes.^9-11

  There are 2 notable limitations in this meta-analysis. First, the qualities of the included studies are relatively poor; the Jadad Scale of all included studies scored 2. Second, the significant heterogeneity and the possible publication bias were found in the meta-analysis. These 2 limitations may lead to bias and need to be considered when evaluating the conclusion.

 The existing evidence shows that hydrocolloid dressings are more effective than gauze dressings for pressure ulcer treatment. The authors suggest that traditional gauze dressings should be abandoned in the treatment of pressure ulcers.

Affiliations: Xiao-Qin He, RN is from the Department of Ophthalmology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, People’s Republic of China. Hong-Lin Chen, MSc is from the School of Nursing, Nantong University, Nantong, Jiangsu, People’s Republic of China.

Address correspondence to:
Xiao-Qin He, RN
pphss@126.com

Disclosure: This work is supported by Nantong Municipal Science and Technology Bureau, grant number BK2013014