Randomised, double blind trial of two loading dose regimens of diamorphine in ventilated newborn infants.
OBJECTIVE
To compare the safety and efficacy of two loading doses of diamorphine in 27 ventilated newborn infants in a randomised double blind trial.


METHODS
Fifty or 200 mcg/kg were infused intravenously over 30 minutes, followed by a 15 mcg/kg/hour continuous infusion. Serial measurements were made of physiology, behaviour, and stress hormones.


RESULTS
Both loading doses produced small but significant falls in blood pressure. The 200 mcg/kg dose produced greater respiratory depression, and two infants deteriorated clinically, requiring resuscitation. Loading reduced respiratory effort in most of the infants, but had little effect on behavioural activity. Stress hormone concentrations were reduced at six hours in both dosage groups; differences between loading doses were not significant. Morphine, morphine-3-glucuronide, and morphine-6-glucuronide were detected in the plasma of all patients. No significant differences in concentrations between loading doses were found.


CONCLUSIONS
Diamorphine reduces the stress response in ventilated newborn infants. A high loading dose confers no benefit, and may produce undesirable physiological effects. A 50 mcg/kg loading dose seems to be safe and effective.
Barker
D P
DP
Department of Neonatal Medicine and Surgery, Nottingham City Hospital.
Simpson
J
J
Pawula
M
M
Barrett
D A
DA
Shaw
P N
PN
Rutter
N
N
D000701:Analgesics, Opioid / Q000008:administration & dosage* / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D003932:Heroin / Q000008:administration & dosage* / Q000494:pharmacology; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007262:Infusions, Intravenous; D010146:Pain / Q000188:drug therapy; D012119:Respiration / Q000187:drug effects; D012121:Respiration, Artificial
D000701:Analgesics, Opioid; D003932:Heroin