Pharmacokinetics of etidocaine in fetal and neonatal lambs and adult sheep.
Etidocaine, 2.5 mg/kg, was injected intravenously into either a nonpregnant adult sheep (N = 7), neonatal lamb (N = 7), or fetal lamb (N = 6), all with catheters in the femoral vessels and urinary bladders. Serial arterial blood and urine samples were obtained over 4 hours and analyzed for unchanged etidocaine using a gas chromatographic technique. The distribution and elimination half-lives of etidocaine in the blood of nonpregnant adults and newborn sheep were similar. The volume of distribution was significantly greater in the newborn (4.64 LK/kg) compared with the adult (1.52 L/kg) as was the total body clearance (87-4 vs 30.3 ml/min/kg). Renal clearance was also significantly greater in the newborn. The data indicate that the newborn lamb is capable of eliminating etidocaine as rapidly as the adult. Following injection of the drug into the fetus, fetal blood concentrations became undetectable after 30 minutes due to placental transfer into the maternal compartment.
D000083:Acetanilides / Q000378:metabolism*; D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism*; D005041:Etidocaine / Q000378:metabolism* / Q000494:pharmacology; D005260:Female; D005333:Fetus / Q000378:metabolism*; D006207:Half-Life; D006439:Hemodynamics / Q000187:drug effects; D007700:Kinetics; D008431:Maternal-Fetal Exchange; D011247:Pregnancy; D012756:Sheep
D000083:Acetanilides; D005041:Etidocaine