title: Enoximone pharmacokinetics in infants.
abstract: Enoximone and enoximone sulphoxide concentrations were measured in plasma of 20 infants, median age 6.0 (range 0.6-49.7) weeks, during and after prolonged continuous infusions. Patients were given enoximone 1 mg kg-1 and an infusion at 10 micrograms kg-1 min-1 just before being weaned from cardiopulmonary bypass (CPB). The infusion was stopped when clinically indicated, after a median 97 (range 24-572) h. Arterial blood samples were taken 30 min and 12 h after CPB, every 24 h during the infusion, and then 2, 4, 8, 12 and 24 h after the infusion was stopped. Pharmacokinetic non-compartmental analysis was performed using TOPFIT software. Fourteen patients who retained normal hepatic function had a median (95% confidence intervals) clearance of 9.7 (6.3-14.1) ml min-1 kg-1, elimination half-life of 5.2 (2.4-6.8) h and a volume of distribution of 3.6 (2.0-5.7) litre kg-1. The six patients with significant hepatic dysfunction had a lower clearance, 5.7 (2.4-14.5) ml min-1 kg-1, and significantly longer elimination half-life, 7.6 (6.5-10.9) h (P = 0.02). Enoximone sulphoxide elimination half-life was significantly prolonged in three patients with renal dysfunction, 16.2 (10.5-17.7) h versus 6.9 (6.1-9.4) h (P = 0.03). These results confirm that enoximone pharmacokinetics in infants is similar to that found in adults. The infusion rate of enoximone should be reduced if hepatic or renal dysfunction supervenes.
authors.affiliation: University of Liverpool, UK.
authors.forename: P D
authors.initials: PD
authors.lastname: Booker
authors.forename: S
authors.initials: S
authors.lastname: Gibbons
authors.forename: J I
authors.initials: JI
authors.lastname: Stewart
authors.forename: A
authors.initials: A
authors.lastname: Selby
authors.forename: E
authors.initials: E
authors.lastname: Wilson-Smith
authors.forename: M
authors.initials: M
authors.lastname: Pozzi
mesh_terms: D017335:Enoximone / Q000097:blood / Q000493:pharmacokinetics*; D006207:Half-Life; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007262:Infusions, Intravenous; D008111:Liver Function Tests; D010726:Phosphodiesterase Inhibitors / Q000097:blood / Q000493:pharmacokinetics*
chemical_list: D010726:Phosphodiesterase Inhibitors; D017335:Enoximone