Post-operative nausea and vomiting in out-patient gynecologic laparoscopy: a comparison of thiopental-nitrous oxide, propofol-nitrous oxide and total intravenous anesthesia using propofol.

An intravenous anesthetic drug, propofol was considered to pose antiemetic action. A randomized controlled trial was conducted to evaluate whether propofol could effectively reduce post-operative nausea and vomiting (PONV) compared to thiopental-nitrous oxide (N2O). One-hundred and eight patients undergoing outpatient gynecologic laparoscopy were assigned to receive 3 techniques of anesthesia; thiopental-N2O (T/N), propofol-N2O (P/N) and total intravenous anesthesia (TIVA) using propofol (P/P). The results showed that in the early period (0-5 hours), post-operative nausea in T/N, P/N and P/P groups was 72 per cent, 44 per cent and 31 per cent, respectively (P = 0.002), and post-operative vomiting was 58 per cent, 36 per cent and 11 per cent respectively (P = 0.00014). Patients in the P/N and P/P groups experienced nausea less frequently than the T/N group [relative risk (RR) = 0.62, (95% CI 0.41-0.93) and RR = 0.42 (0.25-0.72) respectively]. Patients in the P/N and P/P groups experienced vomiting less frequently than the T/N group [RR = 0.62 (0.37-1.04) and RR = 0.19 (0.07-0.5) respectively]. Two patients in the T/N group were admitted because of severe nausea and vomiting. In conclusion, TIVA using propofol and propofol-N2O anesthesia can significantly reduce the incidence of PONV in the early period. Concerning the economic crisis of the country as well as the quality of care, propofol-N2O would be the most appropriate anesthetic of choice.