Background and goal of the study
Neuraxial morphine is recommended as first line treatment for postoperative cesarean section pain but is frequently accompanied by nausea, vomiting and pruritus.   In this study we examined the incidence of post-operative nausea and vomiting (PONV) and pruritus 1 hour and 24 hours following treatment with low dose intrathecal morphine and prophylactic dexamethasone and ondansetron in  parturients undergoing cesarean delivery
Materials and Methods
In this prospective, observational, cohort study, 201 women undergoing cesarean delivery under spinal anesthesia with intrathecal morphine were included. All participants were approached preoperatively and requested to fill out a questionnaire regarding anesthesia experience and previous history of PONV and pruritus. All parturients received spinal anesthetisa with a standardized solution which included hyperbaric bupivacaine 12 mg, fentanyl 20 mcg , preservative-free morphine sulfate 0.1 mg  with prophylactic dexamethasone 4 mg and ondansetron 4 mg. In the post anesthesia care unit and 24 hours postoperatively women were interviewed regarding development and severity grade (0-10) of nausea, vomiting, and pruritus.
Results
In the recovery room there was a 14.5% of nausea and a 77.6% of pruritus.  17.9% of women had nausea and 73.3% of women had pruritus 24 hours after surgery.
 Severe nausea occurred in  7.4% of women, and severe pruritus occurred in 24.9% of women.
Women with nausea and pruritus in the PACU (Post anesthesia care unit) had higher incidence of 24 hour nausea and pruritus, as compared with women who did not suffer from nausea and pruritus in the PACU.
Conclusions
In our study cohort, there was a moderate rate of postoperative nausea and high rate of postoperative pruritus 24 hours after low dose neuraxial morphine administration, in spite of dual prophylaxis treatment with dexamethasone and ondansetron. Our findings suggested that women who experience nausea, vomiting or pruritus in the immediate postoperative period are at increased risk for persistent PONV and pruritus.


04 / Incidence and risk factors for 24-hour postoperative nausea and pruritus after low dose neuraxial morphine in parturients undergoing Cesarean delivery  treated prophylactically with ondonsatron and dexamethasone