Intravenous Paracetamol Decreases Requirements of Morphine in Very Preterm Infants

Objective: To determine whether intravenous paracetamol therapy is effective in pain therapy in premature infants.

Study design: From June 2009 to December 2011, 108 infants born very low gestational age (<32 weeks) (VLGA) were given intravenous paracetamol before the age of 72 hours. The loading dose was 20 mg/kg followed by 7.5 mg/kg every 6 hours. One hundred ten VLGA infants admitted from October 2007 to May 2009 formed the comparison group who received no paracetamol. Intravenous morphine was exclusively used as the opiate. Morphine dosage was calculated as the cumulative dose administered during the neonatal intensive care unit period. Pain symptoms were screened using pain scale scoring Neonatal Infant Acute Pain Assessment Scale. The number of apneas during the neonatal intensive care unit stay, and ventilation days per patient, were calculated.

Results: The mean (SD) total number of paracetamol doses per patient was 16.9 (11.7), and the postnatal age for the first dose was 13.3 (13.8) hours. Infants in the paracetamol group needed significantly fewer morphine doses per patient than the comparisons, 1.78 (4.56) doses vs 4.35 (11.53), P = .044. The exposed had lower cumulative morphine dosage 0.17 (0.45) mg/kg vs 0.37 (0.96) mg/kg, P = .047. There were no differences in the Neonatal Infant Acute Pain Assessment Scale scores, or the numbers of apneas, or ventilation days. There was no evidence of adverse events including hepatic toxicity.

Conclusion: The need for morphine decreased significantly after the introduction of paracetamol for the VLGA infants.