To describe pain assessment, the pattern of analgesic and sedative drug use, and adverse drug reactions in a neonatal intensive care unit (NICU) during the postsurgery phase.

Demographic characteristics, pain scores, and drug use were extracted and analyzed from electronic patient medical files for infants after surgery, admitted consecutively between January 2012 and June 2013.

One hundred and sixty-eight infants were included. Acute (DAN score) and prolonged (EDIN score) pain assessment scores were used in 79% and 64% of infants, respectively, on the 1st day. This percentage decreased over the 7 days following surgery. The weekly average scores postsurgery were 2/15 (±2.2) for the EDIN score and 1.6/10 (±2.0) for the DAN score. The rates of pain control were 88% for the EDIN and 72% for the DAN. The most prescribed opiate drug was fentanyl (98 patients; 58%) with an average dose of 1.8 (±0.6) μg/kg/h. Midazolam was used in 95 patients (56%), with an average dose of 35 (±14) μg/kg/h. A bolus was administered in 7% (±7.4) of the total dose for fentanyl and 8% (±9.3) for midazolam. Similar doses were used in term and preterm neonates. Of 118 patients receiving fentanyl and/or midazolam, 40% presented urinary retention, 28% a weaning syndrome. Paracetamol (155 patients; 92%) and nalbuphine (55 patients; 33%) were the other medications most often prescribed.

The off-label use of fentanyl and midazolam was necessary to treat pain after surgery. Pain assessment should be conducted for all neonates in order to optimize their treatment. Research on analgesic and sedative medicine in vulnerable neonates seems necessary to standardize practices and reduce adverse drug reactions.