Review: little evidence exists for type of dressing or support surface or for nutritional supplements for pressure ulcers
Are different treatments effective for pressure ulcers?
Included studies were randomised controlled trials (RCTs) published in English that reported outcomes that included wound size or complete healing.
Medline, EMBASE/Excerpta Medica, and CINAHL (all to Aug 2008) were searched for RCTs. Journals were hand searched to find other articles. 103 RCTS (n = 5889) were included. Trials were assessed for study quality (“good” [score ⩾4] versus “suboptimal” [score ⩽3] based on methodological criteria [maximum score = 6]), clinical setting, and source of funding.
Clinical heterogeneity precluded valid pooling of study results. 12 RCTs (n = 1214) evaluated support surfaces. 4 lower-quality RCTs of 6 total RCTs reported a benefit for powered support surfaces compared with non-powered support surfaces. 5 RCTs compared different types of powered support surfaces. 1 RCT showed that air-fluidised mattresses reduced wound surface area, whereas alternating pressure mattresses covered with foam increased wound surface area. 7 RCTs (n = 358) evaluated oral nutritional supplements. 1 placebo-controlled RCT showed that a collagen protein supplement improved healing. Results for other nutritional supplements were mixed. 63 RCTs (n = 3330) evaluated interventions involving local wound care. Of 7 high-quality RCTs, 5 showed no difference between types of dressings; 1 RCT showed a greater reduction in wound surface area for calcium alginate than for dextranomer paste (2.39 v 0.27 cm2, p<0.001), and the other RCT showed that oxyquinolone improved wound healing more than lanolin or petrolatum (complete stage II healing 45% v 22%, p<0.05). 9 RCTs (n = 473) evaluated biological agents. 3 placebo controlled RCTs showed that platelet-derived growth factors increased wound healing (1 did not report statistical significance). 1 placebo controlled RCT showed that nerve growth factor improved healing. 21 RCTs (n = 987) evaluated adjunctive therapies. Among the good-quality studies, no benefit was found for electric current, laser, or ultrasound therapies. 2 suboptimal studies of vacuum therapy, compared with other local therapies, did not show improvement.
In people with pressure ulcers, evidence is mixed for use of a specific support surface or dressing over other types. Evidence is also mixed for nutritional supplementation or adjunctive therapies compared with standard care.
A modified version of this abstract appears in ACP Journal Club in Ann Intern Med.
Reddy M, Gill SS, Kalkar SR, et al. Treatment of pressure ulcers: a systematic review. JAMA 2008;300:2647–62.
Clinical impact ratings: Elderly care 5/7; General/internal medicine 6/7; Surgery 6/7; Wound care 6/7
Source of funding Canadian Institutes of Health Research Interdisciplinary Capacity Enhancement.
The review by Reddy et al considered fundamental, local, and adjunctive interventions for treating pressure ulcers. It is important that a systematic review consider all available evidence. 3 databases were searched, but the authors did not search the Cochrane Central Register of Controlled Trials, which includes citations from hand searches, contact with experts, and the grey literature. The authors included only articles written in English, which meant that they excluded 1 of the largest trials (with 294 participants).1 Language bias may result in misleading reports of effects.
Assessing the methodological quality of included trials is crucial; the reviewers did do this and also sought information on trial funding and potential conflicts of interest, which can also contribute to bias. However, they classified trials as “good quality” or “suboptimal” using an arbitrary cut point based on 6 of 10 elements of a checklist for assessing non-pharmacological trials. That said, many of the trials were of poor quality and would have been too small to detect any clinically important differences as statistically significant.
Appropriately, this review did not combine studies in a meta-analysis, as the patients, settings, wounds, and packages of care were too different. Having more high-quality studies with well-described groups would allow investigators to see whether interventions identified as promising offer real clinical benefit, although currently there is an absence of such evidence.
Healthcare professionals will be disappointed in the conclusions of the review: for most interventions, there is no good evidence to inform treatment choices for pressure ulcers. Product marketing should be seen in this context, and higher-quality trials are needed to address the gaps. In the absence of high-quality evidence, most decisions can be guided only by clinical judgement, patient comfort, individual response to interventions, preferences, and costs.