Intrathecal fentanyl is superior to intravenous ondansetron for the prevention of perioperative nausea during cesarean delivery with spinal anesthesia

This study compares intrathecal (IT) fentanyl with IV ondansetron for preve nting intraoperative nausea and vomiting during cesarean deliveries perform ed with spinal anesthesia. Thirty healthy parturients presenting for electi ve cesarean delivery with standardized bupivacaine spinal anesthesia were r andomized to receive 20 mu g IT fentanyl (Group F) or 4 mg IV ondansetron ( Group O) by using double-blinded methodology. At eight specific intervals d uring the surgery, a blinded observer questioned the patient about nausea ( 1 = nausea, 0 = no nausea), observed for the presence of retching or vomiti ng (1 = vomiting or retching, 0 = no vomiting or retching), and recorded a verbal pain score (0-10, 0 = no pain, 10 = worst pain imaginable). Cumulati ve nausea, vomiting, and pain scores were calculated as the sum of the eigh t measurements. Intraoperative nausea was decreased in the IT fentanyl grou p compared with the IV ondansetron group: the median (interquartile range) difference in nausea scores was 1 (1, 2), P = 0.03. The incidence of vomiti ng and treatment for vomiting was not different (P = 0.7). The IT fentanyl group had a lower cumulative perioperative pain score than the IV ondansetr on group; the median difference in the cumulative pain score was 12 (8, 16) (P = 0.0007). The IT fentanyl group required less supplementary intraopera tive analgesia. The median difference in the cumulative fentanyl dose was 1 00 (75, 100) mu g fentanyl, (P = 0.0002).