Gastrointestinal contrast studies in high-risk neonates with suspected necrotising enterocolitis--a note of caution

Meconium Evacuation for Facilitating Feed Tolerance in Preterm Neonates: A Systematic Review and Meta-Analysis

BACKGROUND

A delayed passage of meconium is considered as a risk factor for feed intolerance in preterm neonates.

OBJECTIVES

The aim of this study was to review the effects of different therapeutic agents for meconium evacuation on feed tolerance in preterm neonates.

METHODS

A systematic review of randomised controlled trials (RCTs) of different therapeutic agents for meconium evacuation in preterm neonates (gestation <32 weeks and/or birth weight <1,500 g) using the Cochrane systematic review methodology was undertaken. Databases including Google Scholar were searched in January 2016. The primary outcome was the time to reach full feeds (TFF; ≥120 ml/kg feeds with stoppage of parenteral nutrition >24 h). Secondary outcomes included necrotising enterocolitis (NEC), weight at discharge and adverse effects. The results were summarised as per the GRADE guidelines.

RESULTS

Six RCTs (2 each of glycerine suppository and enema, 1 normal saline enema and 1 oral osmotic contrast agent; n = 442) with a low or unclear risk of bias were included. The pooled estimate (random effects model) showed no reduction in TFF [mean difference (MD) -0.03, 95% CI -2.47, 2.41, p = 0.98; level of evidence: low]. No differences in NEC [risk ratio (RR) 1.71, 95% CI 0.63, 4.65, p = 0.30; level of evidence: low] and weight at discharge (MD -0.08, 95% CI -0.30, 0.15, p = 0.50; level of evidence: low) were found. The trial assessing oral osmotic contrast agents reported a trend towards a higher incidence of NEC ≥ stage II. There were no other adverse effects.

CONCLUSION

Limited low-quality evidence indicates that prophylactic glycerine suppository, small volume glycerine/normal saline enema or oral osmotic contrast agents to evacuate meconium did not reduce TFF in preterm neonates. Large, well-designed trials are essential to study this clinically significant issue.

Necrotizing enterocolitis: controversies and challenges

Necrotizing enterocolitis is a devastating intestinal disease that affects ~5% of preterm neonates. Despite advancements in neonatal care, mortality remains high (30–50%) and controversy still persists with regards to the most appropriate management of neonates with necrotizing enterocolitis. Herein, we review some controversial aspects regarding the epidemiology, imaging, medical and surgical management of necrotizing enterocolitis and we describe new emerging strategies for prevention and treatment.

Prevention and treatment of necrotising enterocolitis in preterm neonates

Prevention and treatment of NEC has become an area of priority for research due to the increasing number of preterm survivors at risk, and the significant mortality and morbidity related to the illness. Probiotic supplementation appears to be a promising option for primary prevention of NEC but further large trials are necessary for documenting their safety in terms of sepsis as well as long-term neurodevelopmental outcomes and immune function. As new frontiers including immunomodulating agents like pentoxifylline continue to be explored, the impact of well-established simple strategies like antenatal glucocorticoid therapy, and early and preferential use of breast milk must not be forgotten. Clinical research on manifestations of ileus of prematurity, and feeding in the presence of common risk factors such as IUGR is needed. Safety of minimal enteral feeds in terms of NEC and benefits of standardised feeding regimens need to be confirmed. Association of common clinical practices such as red cell transfusions, H2 receptor blockade, and thickening of feeds with NEC warrants attention. An approach utilising a package of potentially better practices seems to be the most appropriate strategy for the prevention and treatment of NEC.