High-carbohydrate, high-protein, low-fat tube feeds versus low-carbohydrate, high-protein, high-fat tube feeds for patients with severe burns

Patients with severe burn injuries have increased metabolic needs. For this and other reasons, they are often fed a formula through a tube inserted directly into the stomach or small intestine, a process known as enteral feeding. Aggressive enteral feeding of burn patients with a high-protein diet is a core component of the treatment of severe burn injuries. However, the optimal proportions of fats and carbohydrates in feeding formulas are unknown. This review of 93 burn patients in two randomized controlled trials found that high-carbohydrate, high-protein, low-fat enteral feeds reduced incidence of pneumonia compared with low-carbohydrate, high-protein, high-fat enteral feeds in patients hospitalized with severe burn injuries. No conclusions could be made about the effect of different enteral feeding regimens on death.

The strength of this review's findings were limited by the number, size, and quality of eligible trials. Further research is needed before strong scientific conclusions and sound clinical recommendations can be made.

Authors' conclusions: 

The available evidence suggests that use of high-carbohydrate, high-protein, low-fat enteral feeds in patients with at least 10% TBSA burns might reduce the incidence of pneumonia compared with use of a low-carbohydrate, high-protein, high-fat diet. The available evidence is inconclusive regarding the effect of either enteral feeding regimen on mortality. Note that the available evidence is limited to two small studies judged to be of moderate risk of bias. Further research is needed in this area before strong conclusions can be drawn.

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Background: 

Severe burn injuries increase patients' metabolic needs. Aggressive high-protein enteral feeding is used in the post-burn period to improve recovery and healing.

Objectives: 

To examine the evidence for improved clinical outcomes in burn patients treated with high-carbohydrate, high-protein, low-fat enteral feeds (high-carbohydrate enteral feeds) compared with those treated with low-carbohydrate, high-protein, high-fat enteral enteral feeds (high-fat enteral feeds).

Search strategy: 

We searched the Cochrane Injuries Group Specialised Register (searched 28 Nov 2011), Cochrane Central Register of Controlled Trials (The Cochrane Library 2011, Issue 4), MEDLINE (Ovid) 1950 to Nov (Week 3) 2011, EMBASE (Ovid), ISI Web of Science: Science Citation Index Expanded (SCI-EXPANDED) (1970 to Nov 2011), ISI Web of Science: Conference Proceedings Citation Index-Science (CPCI-S) (1990 to Nov 2011), PubMed (Searched 28 Nov 2011). Online trials registers and conference proceedings were also searched to April 2010.

Selection criteria: 

We included all randomized controlled trials (RCTs) comparing high-carbohydrate enteral feeds to high-fat enteral feeds for treatment of patients with 10% or greater total body surface area (TBSA) burns in the immediate post-burn period, with data for at least one of the pre-specified outcomes.

Data collection and analysis: 

Two authors collected and analysed the following data: mortality, incidence of pneumonia and days on ventilator. Meta-analysis could only be performed for the outcomes mortality and incidence of pneumonia. A random-effects model was used for all comparisons.

Main results: 

Two RCTs, reporting results from 93 patients, were included in this review. Patients given a high-carbohydrate feeding formula had an odds ratio (OR) of 0.12 (95% confidence interval (CI) 0.04 to 0.39) for developing pneumonia compared to patients given a high-fat enteral formula (P value = 0.0004). Patients given a high-carbohydrate formula had an OR of 0.36 (95% CI 0.11 to 1.15) for risk of death compared to patients given a high-fat enteral formula; this difference did not reach statistical significance (P value = 0.08). Risk of bias in these studies was assessed as high and moderate.