title: The maternal and fetal cardiovascular effects of epidural morphine in the sheep model.
abstract: Interest in the use of epidural narcotics for analgesia has been widespread since the demonstration of opiate receptors in the spinal cord in the mid nineteen-seventies. Recently, several studies have attempted to evaluate the effectiveness of epidural narcotics for the relief of pain in labor and after cesarean section. Using the chronically catheterized maternal-fetal sheep model, we injected 5 mg of preservative-free morphine into the epidural space. No statistically significant changes were observed, neither in maternal or fetal arterial pressure and acid-base status, nor in maternal central venous pressure, systemic and pulmonary vascular resistance, cardiac output, or intrauterine pressure (p greater than 0.05). There was a significant, although small, decrease in maternal heart rate (8%) and uterine blood flow (9%) at 120 minutes (p less than 0.05), and then a return to control values. The maternal levels of morphine peaked at 15 minutes (29 ng/ml) and the fetal levels of morphine peaked at 90 minutes (3 to 4 ng/ml). We conclude that the injection of 5 mg of morphine into the maternal epidural space has no adverse effect on mother or fetus in the sheep model.
mesh_terms: D000136:Acid-Base Equilibrium; D000767:Anesthesia, Epidural; D000773:Anesthesia, Obstetrical; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D005260:Female; D005318:Fetal Heart / Q000187:drug effects; D005333:Fetus / Q000187:drug effects* / Q000502:physiology; D006439:Hemodynamics / Q000187:drug effects*; D008431:Maternal-Fetal Exchange; D009020:Morphine / Q000008:administration & dosage / Q000494:pharmacology*; D011247:Pregnancy; D011652:Pulmonary Circulation / Q000187:drug effects; D012756:Sheep; D014599:Uterus / Q000098:blood supply; D014655:Vascular Resistance / Q000187:drug effects
chemical_list: D009020:Morphine