NALMEFENE OR NALOXONE FOR PREVENTING INTRATHECAL OPIOID MEDIATED SIDE-EFFECTS IN CESAREAN DELIVERY PATIENTS

This study was designed to evaluate the efficacy of nalmefene vs. nalo xone in preventing side effects resulting from intrathecal opioids, in patients undergoing cesarean delivery. Eighty patients who were sched uled for elective cesarean delivery under spinal anesthesia were inclu ded in a double-blind, placebo-controlled study. Patients were randomi zed into four groups: saline; intravenous nalmefene 0.25 mu g.kg(-1) e very 12 h x 2; intravenous nalmefene 0.5 mu g.kg(-1) every 12 h x 2; a nd naloxone infusion 48 mu g.h(-1) (1.2 mu g.ml(-1)). There were no si gnificant differences among the groups with respect to pain, sedation, satisfaction, or the occurrence or treatment of pruritus or nausea. T here was a significant difference among the groups with respect to the occurrence of vomiting (P<0.03): both nalmefene groups had a higher r ate of vomiting than did the control group; the 0.25 mu g.kg(-1) nalme fene group had a higher rate than did the naloxone group. The use of n arcotic antagonists does not result in improved comfort in obstetrical patients receiving intrathecal morphine and fentanyl.