Primary peritoneal drainage in neonates with necrotizing enterocolitis associated with congenital heart disease: a single experience in a Brazilian tertiary center

Necrotizing enterocolitis (NEC) is a common condition in preterm infants. The risk factors that contribute to NEC include asphyxia, apnea, hypotension, sepsis, and congenital heart diseases (CHD). The objective of this study was to evaluate the association between the treatment (surgery or drainage) and unfavorable outcomes in neonates with NEC and congenital heart diseases (NEC+CHD). A 19-year retrospective cohort study was conducted (2000-2019). Inclusion criterion was NEC Bell II stage. Exclusion criteria were associated malformation or genetic syndrome and those who did not undergo echocardiography or had a Bell I diagnosis. We included 100 neonates: NEC (n=52) and NEC+CHD (n=48). The groups were subdivided into NEC patients undergoing surgery (NECS, n=31), NEC patients undergoing peritoneal drainage (NECD, n=19), NEC+CHD patients undergoing surgery (NECCAS, n=21), and NEC+CHD patients who were drained (NECCAD, n=29). Multivariate analysis was performed to estimate the relative risk of death and the length of stay. Covariates were birth weight and gestational age. The group characteristics were similar. The adjusted relative risk of death was higher in the drainage groups [NECD (Adj RR=2.70 (95%CI: 1.47; 4.97) and NECCAD (Adj RR=1.97 (95%CI: 1.08; 3.61)], and they had the shortest time to death: NECD=8.72 (95%CI: 3.10; 24.54) and NECCAD=5.32 (95%CI: 1.95; 14.44). We concluded that performing primary peritoneal drainage in neonates with or without CHD did not improve the number of days of life, did not decrease the risk of death, and was associated with a higher mortality in newborns with NEC and clinical instability.