NEW YORK (Reuters Health) – Prophylactic antibiotics may improve survival of burn patients, a meta-analysis suggests, although the authors acknowledge that the quality of the supporting data is weak.

A number of factors increase the risk of infection in burn patients, yet “there is a broad and uniform consensus in the current literature that prophylaxis with systemic antibiotics should not be given to patients with severe burns,” the authors point out.

In their analysis, however, systemic prophylactic antibiotics reduced the odds of in-hospital death by nearly 50%.

In theory, they imply, this finding should not be surprising. “Antibiotic prophylaxis reduces mortality, bacteremia, and ventilator associated pneumonia among patients in intensive care units. Similarities between intensive care and burns patients suggest possibly similar benefit of prophylaxis,” senior author Dr. Mical Paul, from Rabin Medical Center, Tel-Aviv, Israel, and colleagues note.

However, “recommendations for management do not address systemic antibiotic prophylaxis or explicitly state that prophylactic antibiotics are not recommended.”

Reasons cited for not giving prophylactic antibiotics to burns patients include a lack of benefit and an increased risk of adverse events, particularly Clostridium difficile-associated colitis and selection of antibiotic-resistant microbes.

To sort out the benefits and risks of antibiotic prophylaxis in this setting, Dr. Paul’s team conducted a systematic review and meta-analysis of data from 17 randomized or quasi-randomized controlled trials identified through a search of PubMed and other sources. The studies were published between 1966 and 2009 and featured 1113 patients. In each study, a form of prophylaxis—systemic, non-absorbable, or topical—was compared with placebo or no treatment.

“Most trials recruited patients with burns over more than 20% of total body surface area,” the researchers said.

In the February 17th Online First issue of the British Medical Journal, they report that systemic antibiotic prophylaxis, given for 4 to 14 days after admission, cut all-cause in-hospital mortality by 46%. The number needed to treat was 8 and the control event rate was 26%.

By contrast, use of perioperative non-absorbable or topical antibiotics alone did not significantly affect mortality, the researchers found.

Systemic antibiotic prophylaxis appeared to reduce the risk of pneumonia, while perioperative prophylaxis cut the risk of wound infections. Use of anti-staphylococcal antibiotics reduced infection or colonization with Staphylococcus aureus.

In terms of adverse effects, data from three trials indicated a significant increase in resistance to the antibiotic used for prophylaxis.

Still, the authors caution that none of the findings are definitive as the overall methodologic quality of the studies was poor.

“We have shown a discrepancy between current guidelines for management of burns patients recommending against antibiotic prophylaxis and the evidence showing a reduction of about 50% in all cause mortality with systemic antibiotic prophylaxis,” the authors conclude.

“Given the paucity and limitations of the available evidence, this should serve mainly as an urgent call for a large randomized controlled trial,” they add. Moreover, “future trials should assess a full selective decontamination regimen including systemic and non-absorbable antibiotics.”

Reference:

BMJ Online First 2010.