Intravenous acetaminophen (at 15 mg/kg/dose every 6 hours) in critically ill preterm neonates with patent ductus...

Acetaminophen has been increasingly used in treating patent ductus arteriosus (PDA) in preterm neonates. Variations were observed in the dosing regimen of acetaminophen across the studies. There is hardly any data available for a relatively higher dose of intravenous acetaminophen (15 mg/kg/dose every 6 hours) in the preterm population. We present here the results of a prospective study with this dose of intravenous acetaminophen for treating PDA in critically ill preterm neonates.

Preterm neonates (≤37 weeks of gestational age) with haemodynamically significant PDA were enrolled. Intravenous acetaminophen at 15 mg/kg/dose every 6 hours was administered. Echocardiographic monitoring, liver and renal function tests were carried out. Standard definitions were adhered for defining acute kidney injury (AKI) and hepatotoxicity.

Fifty-five neonates were recruited. Following the first dose, less than half had their serum acetaminophen concentrations in the therapeutic range. Extreme preterm neonates were less likely to have a sustained therapeutic acetaminophen concentration after the first dose. Following multiple doses and at steady state, 97.2% and 98.8% respectively were in the therapeutic range. Forty-three (78.2%) neonates had successful closure of the ductus arteriosus of which 22 were extreme preterm, 17 were very preterm and 4 were late preterm neonates; and considering their birthweights, 21 were extremely low, 16 were very low and 6 were low birthweight categories. Ten neonates had elevated alanine aminotransferase levels with three in the low-to-moderate risk of hepatotoxicity category. Eight neonates had altered renal function tests indicating AKI.

Intravenous acetaminophen at 15 mg/kg/dose every 6 hours was efficacious in 78.2% of the preterm neonates with PDA. We observed a lower incidence of hepatotoxicity, and AKI in the study population. No association was observed between the serum acetaminophen concentrations and PDA closure.