Topical emollient for preventing infection in preterm infants

Breakdown of the developmentally immature epidermal barrier may permit entry for micro-organisms leading to invasive infection in preterm infants. Topical emollients may improve skin integrity and barrier function and thereby prevent invasive infection, a major cause of mortality and morbidity in preterm infants.

To assess the effect of topical application of emollients (ointments, creams, or oils) on the incidence of invasive infection, other morbidity, and mortality in preterm infants.

We used the standard search strategy of the Cochrane Neonatal Review group to search the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 7), MEDLINE via PubMed (1966 to August 2015), EMBASE (1980 to August 2015), and CINAHL (1982 to August 2015). We also searched clinical trials databases, conference proceedings, previous reviews and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

Randomised or quasi-randomised controlled trials that assessed the effect of prophylactic application of topical emollient (ointments, creams, or oils) on the incidence of invasive infection, mortality, other morbidity, and growth and development in preterm infants.

Two review authors assessed trial eligibility and risk of bias and undertook data extraction independently. We analysed the treatment effects in the individual trials and reported the risk ratio and risk difference for dichotomous data and mean difference for continuous data, with respective 95% confidence intervals. We used a fixed-effect model in meta-analyses and explored the potential causes of heterogeneity in subgroup analyses.

We identified 18 eligible primary publications (21 trial reports). A total of 3089 infants participated in the trials. The risk of bias varied with lack of clarity on methods to conceal allocation in half of the trials and lack of blinding of caregivers or investigators in all of the trials being the main potential sources of bias.Eight trials (2086 infants) examined the effect of topical ointments or creams. Most participants were very preterm infants cared for in health-care facilities in high-income countries. Meta-analyses did not show evidence of a difference in the incidence of invasive infection (typical risk ratio (RR) 1.13, 95% confidence interval (CI) 0.97 to 1.31; low quality evidence) or mortality (typical RR 0.87, 95% CI 0.75 to 1.03; low quality evidence).Eleven trials (1184 infants) assessed the effect of plant or vegetable oils. Nine of these trials were undertaken in low- or middle-income countries and all were based in health-care facilities rather than home or community settings. Meta-analyses did not show evidence of a difference in the incidence of invasive infection (typical RR 0.71, 95% CI 0.51 to 1.01; low quality evidence) or mortality (typical RR 0.94, 95% CI 0.81 to 1.08; moderate quality evidence). Infants massaged with vegetable oil had a higher rate of weight gain (about 2.55 g/kg/day; 95% CI 1.76 to 3.34), linear growth (about 1.22 mm/week; 95% CI 1.01 to 1.44), and head growth (about 0.45 mm/week; 95% CI 0.19 to 0.70). These meta-analyses contained substantial heterogeneity.

The available data do not provide evidence that the use of emollient therapy prevents invasive infection or death in preterm infants in high-, middle- or low-income settings. Some evidence of an effect of topical vegetable oils on neonatal growth exists but this should be interpreted with caution because lack of blinding may have introduced caregiver or assessment biases. Since these interventions are low cost, readily accessible, and generally acceptable, further randomised controlled trials, particularly in both community- and health care facility-based settings in low-income countries, may be justified.