Fentanyl pharmacokinetics and hemodynamic effects in preterm infants during ligation of patent ductus arteriosus.
A bolus of 30 micrograms X kg-1 fentanyl was given to nine preterm infants (gestational age 31.8 +/- 4.7 weeks, weight 1100 +/- 309 g) for induction of anesthesia for ligation of a patent ductus arteriosus. Thirty minutes after the injection, fentanyl plasma concentrations were between 7.7 and 13.6 ng X ml-1. Elimination half-life was 6-32 hr (mean +/- SD, 17.7 +/- 9.3). Systolic blood pressure remained stable throughout surgery. There was a gradual increase in heart rate from 159 +/- 12 min-1 at the time of skin incision to 173 +/- 15 min-1 at the time of skin closure (P less than 0.05). Fentanyl plasma concentrations remained virtually unchanged between 30 min (10.6 +/- 1.9 ng X ml-1) and 120 min (9.6 +/- 1.6 ng X ml-1); whereas at the end of surgery most infants moved and breathed spontaneously. This phenomenon can be explained by redistribution of fentanyl from brain into pharmacodynamically inert tissues.
D000771:Anesthesia, Intravenous; D001794:Blood Pressure / Q000187:drug effects; D004374:Ductus Arteriosus, Patent / Q000097:blood / Q000601:surgery*; D005260:Female; D005283:Fentanyl / Q000009:adverse effects / Q000097:blood*; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000097:blood / Q000601:surgery*; D007700:Kinetics; D008026:Ligation; D008297:Male; D010197:Pancuronium
D010197:Pancuronium; D005283:Fentanyl