Prophylaxis of intra- and postoperative nausea and vomiting in patients during cesarean section in spinal anesthesia

BACKGROUND This paper describes a randomized prospective study conducted in 308 patients undergoing caesarean section in spinal anaesthesia at a single hospital between 2010 and 2012 to find a suitable anti-emetic strategy for these patients. MATERIAL AND METHODS Spinal anesthesia was performed in left prone position, at L3/L4 with hyperbaric 0.5% Bupivacaine according to a cc/cm body height ratio. There were no opioids given peri-operatively. The patients received either no prophylaxis (Group I) or tropisetron and metoclopramide (Group II) or dimenhydrinate and dexamethasone (Group III), or tropisetron as a single medication (Group IV). The primary outcome was nausea and/or vomiting (NV) in the intraoperative, early (0-2 h) or late (2-24 h) postoperative period. Multivariate statistical analysis was conducted with a regression analysis and a backward elimination of factors without significant correlation. RESULTS All prophylactic agents significantly reduced NV incidence intraoperatively. Relative risk reduction for NV by prophylaxis was most effective (59.5%) in Group II (tropisetron and metoclopramide). In Group III (dimenhydrinate and dexamethasone), NV risk was reduced by 29.9% and by 28.7% in Group IV (tropisetron mono-therapy). The incidence of NV in the early (0?2 h) and the late (2?24 h) postoperative period was low all over (7.8%), but the relative risk reduction of NV in the early postoperative period was 54.1% (Group IV), 45.1% (Group III), and 34.8% (Group II), respectively. In the late postoperative period, there was no significant difference between the 4 groups. CONCLUSIONS We recommend a prophylactic medication with tropisetron 2 mg and metoclopramide 20 mg for patients during caesarean section. These agents are safe, reasonably priced, and highly efficient in preventing nausea and vomiting.