Objective Necrotizing enterocolitis (NEC) usually occurs in Very Low Birth Weight Infants and it is the most common gastrointestinal emergency in the Neonatal Intensive Care Unit. Since NEC mortality and morbidity are extremely high, early diagnosis becomes essential. Increased gastric residuals are used to define NEC stage, but studies on qualitative and quantitative residual features as markers of NEC risk are still lacking. Primary goal of this analysis was evaluation of gastric residuals role in early identification of patients at risk of NEC. The secondary goal was investigation of NEC risk factors, besides prematurity and birth weight.
Methods We performed a case-control study: NEC cases were matched with control subjects by gestational age and birthweight. Feeding tolerance was assessed by maximum gastric residual volume, maximum residual as percentage of previous feeding and residual appearance. Mortality and NEC risk factors were evaluated.
Results 844 VLBWI were admitted to the NICU during the study period with an overall mortality before discharge of 14.6%. NEC frequency was 2%. Patent ductus arteriosus was significantly associated with NEC. Mean maximum residual from birth to NEC onset and maximum residual as percentage of the corresponding feed volume were significantly higher in cases than in controls, as well as percentage of infants with hemorrhagic residuals.
Conclusions Gastric residuals are a marker of feeding intolerance and bloody residuals seem to be the best predictor for NEC. For early detection of VLBWI at risk of NEC, both gastric residual volumes and bloody residuals represent an early relevant marker.