Fluid overload in newborns undergoing abdominal surgery: a retrospective study.

BACKGROUND: Fluid management in newborns undergoing surgery can be challenging due to difficulties in accurately assessing volume status in context of high fluid needs perioperatively and postoperative third-space fluid loss. Fluid overload can be associated with an increase in neonatal morbidity and mortality.

OBJECTIVE: Our objective was to determine the burden of fluid overload and to evaluate their associations with adverse effects among infants undergoing abdominal surgery at a tertiary perinatal center.

METHODS: Patients from our Neonatal Intensive Care Unit who underwent abdominal surgery from January 2017 to June 2019 were included in this retrospective cohort study. Fluid balance was assessed based on the maximum percentage change in body weight at 3- and 7-postoperative days.

RESULTS: Sixty infants were included, with a median [interquartile range] gestational age (GA) of 29 [25-36] weeks and birth weight of 1240 [721-2871] grams. The median daily actual fluid intake was significantly higher than the prescribed fluid intake in the first 7 postoperative days (163 vs. 145 mL/kg, p  < .01). The median maximum change of body weight by postoperative days 3 and 7 were 6% [3-13] and 11% [5-17], respectively. A 1% increase in weight within the first 3 postoperative days was associated with a 0.6-day increase for invasive ventilatory support ( p  = .012). The correlation was still significant after adjusting for GA ( p  = .033).

CONCLUSION: Fluid overload within the first 3 postoperative days was associated with an increase in ventilator support among infants. Careful attention to fluid management may affect the optimization of outcomes for newborns undergoing abdominal surgery.