Context:

Chronic wounds are a major source of morbidity, disability, and mortality, having a significant impact on public health and healthcare resource expenditure.

Objectives:

To systematically review evidence on low-level laser therapy or vacuum-assisted closure on wound-healing outcomes.

Data Sources:

MEDLINE® (through June 8, 2004), EMBASE (through June 14, 2004), and the Cochrane Controlled Trials Register (through 2003) were searched. Primary published evidence was supplemented with recent meeting abstracts and clinical trial protocols.

Study Selection:

Included studies were randomized, controlled trials (RCTs) of one of the following comparison types: alternative intervention; incremental benefit; or placebo. Low-level laser trials had to include only chronic wounds, while vacuum-assisted closure trials could include various wound types. Trials were full-text journal articles reporting on at least one outcome of interest. Primary outcomes of interest were incidence of complete wound closure, time to complete closure, and adverse events.

Data Extraction:

Titles and abstracts were screened by a single reviewer. A second reviewer reviewed citations marked ineligible for full-text retrieval. Rater agreement was required to exclude citations. Following retrieval, one reviewer determined whether an article should be included, excluded, or discussed with another reviewer. One reviewer performed primary data abstraction; evidence tables were fact-checked by a second reviewer.

Data Synthesis:

For low-level laser therapy, 11 studies (n=413) met study selection criteria. For vacuum-assisted closure, 6 studies (n=135) met study selection criteria. Outcomes of interest were summarized in tables and synthesized across studies.

Conclusions:

Evidence was limited by poor trial quality. Concerns centered on: randomization adequacy; group comparability at baseline and follow-up; use of complete healing as the primary endpoint; adjustment for confounders; and intention-to-treat analysis. Sample sizes were generally small, making it difficult to find statistically significant differences between groups.

The best available trial did not show a higher probability of complete healing at 6 weeks with the addition of low-level laser compared to sham laser treatment added to standard care. Study weaknesses were unlikely to have concealed existing effects. Future studies may determine whether different dosing parameters or other laser types may lead to different results.

Vacuum-assisted closure trials did not find a significant advantage for the intervention on the primary endpoint, complete healing, and did not consistently find significant differences on secondary endpoints and may have been insufficiently powered to detect differences. Ongoing RCT protocols may provide better evidence on outcomes of interest.

Given the sparse evidence for these two interventions, at the present time, it is not possible to find variables in these trials that may be associated with better results.