Objectives: To assess the influence of an infusion of clonidine 1 μg/kg/hr on fentanyl and midazolam requirement in ventilated newborns and infants.
Design: Prospective, double-blind, randomized controlled multicenter trial. Controlled trials.com/ISRCTN77772144.
Setting: Twenty-eight level 3 German PICUs/neonatal ICUs.
Patients: Ventilated newborns and infants: stratum I (1-28 d), stratum II, (29-120 d), and stratum III (121 d to 2 yr).
Interventions: Patients received clonidine 1 μg/kg/hr or placebo on day 4 after intubation. Fentanyl and midazolam were adjusted to achieve a defined level of analgesia and sedation according to Hartwig score.
Measurements and main results: Two hundred nineteen infants were randomized; 212 received study medication, 69.7% were ventilated in the postoperative care and 30.3% for other reasons. Primary endpoint: consumption of fentanyl and midazolam in the 72 hours following the onset of study medication (main observation period) in the overall study population. The confirmatory analysis of the overall population showed no difference in the consumption of fentanyl and midazolam. Explorative age-stratified analysis demonstrated that in stratum I (n = 112) the clonidine group had a significantly lower consumption of fentanyl (clonidine: 2.1 ± 1.8 μg/kg/hr, placebo: 3.2 ± 3.1 μg/kg/hr; p = 0.032) and midazolam (clonidine: 113.0 ± 100.1 μg/kg/hr, placebo: 180.2 ± 204.0 μg/kg/hr; p = 0.030). Strata II (n = 43) and III (n = 46) showed no statistical difference. Sedation and withdrawal-scores were significantly lower in the clonidine group of stratum I (p < 0.001). Frequency of severe adverse events did not differ between groups.
Conclusions: Clonidine 1 μg/kg/hr in ventilated newborns reduced fentanyl and midazolam demand with deeper levels of analgesia and sedation without substantial side effects. This was not demonstrated in older infants, possibly due to lower clonidine serum levels.