Pulmonary and systemic vascular response to promethazine in conscious lambs.
Promethazine is an antihistamine commonly used for sedation in clinical pediatric medicine. We studied the cardiovascular effects of promethazine in normoxic, conscious, chronically instrumented neonatal lambs. Eight lambs received 1.3 mg/kg of promethazine intravenously (i.v.) while at rest. In all lambs, promethazine led to elevations of pulmonary vascular resistance, mean pulmonary arterial pressure, mean transpulmonary pressure, mean left atrial pressure, and the ratio of pulmonary-to-systemic vascular resistance. In addition, five (63%) of the lambs demonstrated an increase in mean systemic arterial pressure and systemic vascular resistance to promethazine. A subgroup of three lambs, which tended to be younger, failed to demonstrate the systemic vascular response to promethazine. Promethazine given i.v. has important cardiovascular effects. We hypothesize that promethazine used for sedation before cardiac catheterization in children may alter subsequent hemodynamic observations.
Covert
R F
RF
Department of Pediatrics, University of Florida College of Medicine, Gainesville.
Drummond
W H
WH
Webb
I B
IB
Gimotty
P A
PA
D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D001775:Blood Circulation / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D003243:Consciousness; D003326:Coronary Circulation / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D011398:Promethazine / Q000494:pharmacology*; D011652:Pulmonary Circulation / Q000187:drug effects*; D012756:Sheep; D014655:Vascular Resistance / Q000187:drug effects
D011398:Promethazine