Advantages of fentanyl over morphine in analgesia for ventilated newborn infants after birth: A randomized trial

Objective: To compare the efficacy and adverse effects of fentanyl or morph ine analgesia during the first 2 days of life in newborn infants who underw ent mechanical ventilation. Study design: In a randomized double-blind trial, 163 infants were allocate d to receive a continuous infusion of fentanyl (10.5 mu g/kg over a 1-hour period followed by 1.5 mu g/kg/hr) or morphine (140 mu g/kg over a 1-hour p eriod followed by 20 mu g/kg/hr) for at least 24 hours. The sever;ty of pai n was assessed with physiological parameters, a behavioral pain scale, and stress hormone concentrations before and 2 and 24 hours after the start of treatment. Results: The analgesic effect was similar in both groups, as judged by the pain scale. Plasma adrenaline and noradrenaline concentrations decreased si gnificantly from 0 to 24 hours in both groups. Median adrenaline decrease w as -0.5 nmol/L (interquartile range [IQR] -1.1;0.0) in the fentanyl and -0. 7 nmol/L (IQR -1.3;0.1) in the morphine group, noradrenaline -2.1 nmol/L (I QR -9.0:0.2), and 3.0 nmol/L (IQR -7.5;0.3), respectively. p-endorphin decr eased significantly only in the fentanyl group (-14 pmol/L (IQR -28;-7), P < .05). Decreased gastrointestinal motility was less frequent in the fentan yl group (23% vs 47%, P < .01). Conclusions: With at least as effective analgesia as with morphine, fentany l had fewer side effects. Fentanyl may be superior to morphine For short-te rm postnatal analgesia in newborn infants.