Effect of silver‐containing hydrofiber dressing on burn wound healing: A meta‐analysis and systematic review

Silver sulfadiazine is commonly used to treat local burn wounds. Aquacel‐Ag is a hydrogen fiber dressing containing ionic silver that reduces burn wound infection and promotes antimicrobial activity. It is necessary to compare the efficacy of the two in the healing of burns.


| Literature inclusion and exclusion criteria
Inclusion criteria were as follows: ① Study type: RCTs; ② Subjects: aged ≥18 years, diagnosis of burns conforming to Total Burn Care, 6 Surgery, 7 with no restriction of sample size, sex, and language; ③ Intervention measures: according to different intervention measures, they were divided into observation group and control group; patients in the observation group were treated with Aquacel-Ag dressings, while those in the control group were treated with silver sulfadiazine cream; ④ Outcome measures: wound healing time, wound healing rate on Day 7, tumor necrosis factorα (TNFα), times of dressing change, and adverse reactions; ⑤ Literature with available data. Repeated publications were considered as one study.
Exclusion criteria were as follows: ① Literature with incomplete original data; ② review, expert experience, case report, etc.; ③ other studies such as pharmacology and pharmacokinetics; ④ ineligible literature with significant study design defects; ⑤ study subjects were less than 18 years old or did not meet the diagnostic criteria for burns.

| Literature screening and data extraction
Literature screening and data extraction were performed independently by two researchers. Titles and abstracts were read, and eligible articles were included. Then, the full-text review was carried out and the following information was extracted and recorded: baseline data for study subjects, first author, publication year, study type, and outcome measures. In case of any disagreement, the two researchers discussed it together or asked a third party to review it, if necessary, to reach an agreement.

| Literature quality evaluation
The quality of the included literature was assessed using the modified Jadad scale 8 (including the method of random sequence generation, allocation concealment, use of blinding, and whether the data was complete). A total score >3 indicated high quality and ≤3 suggested low quality. If there was controversy during the screening process, the agreement was reached after a joint discussion or review by a third person, and the authors of the original literature were contacted if necessary.

| Statistical analysis
The extracted data were saved using Excel and then data processing and meta-analysis were performed using RevMan 5.0 software. Enumeration data were presented as odds ratios with their 95% confidence intervals [OR (95% CI of OR)]. The chi-squared test (χ 2 ) and p-value were used to evaluate heterogeneity between studies. If I 2 ≤ 50% and p ≥ 0.05 simultaneously, the heterogeneity was small and the fixed-effects model was used for analysis. I 2 > 50% or p < 0.05 indicated significant heterogeneity, and the causes of heterogeneity were analyzed, or subgroup analysis was performed; if the heterogeneity still existed, the random-effects model was used for analysis. p < 0.05 indicates a statistically significant difference.

| Literature search results
A total of 379 articles were retrieved, including 194 articles from Wanfang, 153 from CNKI, and the other 32 articles from other databases. After removing 34 repeated articles, we read the titles and abstracts of the articles and further excluded 102 articles that did not meet the requirements (rat experiments, case report, review, etc.).

| Basic characteristics of included studies
All the included studies were comparable in grouping and in baseline data of study subjects. Main outcome measures in these studies included wound healing time, wound healing rate, TNFα level, times of dressing change, and adverse reactions. The characteristics of the 11 included literature are shown in Table 1.

| Literature quality evaluation results
Eleven literature [9][10][11][12][13][14][15][16][17][18][19] were evaluated by a Jadad score, and it was found that all literature had Jadad score >3 points, suggesting high literature quality, and there was no description of withdrawals and dropouts ( Table 2).  Figure 2D], and the differences were statistically significant.   this study ( Figure 3A). To further verify the stability of the results of this study, sensitivity analysis was performed, and after removing the study by Mao Ling, the wound healing time of the observation group was still lower than that of the control group, and the difference was statistically significant [MD = −4.14, 95% CI (−5.71-−2.57), p < 0.001; Figure 3B].

| Adverse reactions
A total of eight articles 9-13,15,16,19 mentioned adverse reactions; four studies 9,10,12,13 demonstrated that no patient developed adverse reactions during the experiment, this studies 15,16,19 showed no statistical difference in the incidence of adverse reactions between the two groups, and the remaining 1 study 11 showed that the incidence of adverse reactions in the control group was higher than that in the observation group (p < 0.05).

| DISCUSS ION
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