and log-odds ratios, calculated from the incidence data of each individual trial, were determined and A number of prospective randomized comparator combined using a fixed-effects meta-analysis apstudies have suggested that there is a reduction in proach. Patients who received maintenance of anpost-operative nausea and vomiting following mainaesthesia with propofol had a significantly lower tenance of anaesthesia with propofol compared with incidence of post-operative nausea and vomiting in inhalational agents. We analysed these studies in more comparison with inhalational agents regardless of indetail by examining the effects of induction agent, duction agent, choice of inhalation agent, presence/ choice of inhalation agent, presence/absence of niabsence of nitrous oxide, age of patient or use of trous oxide, age of patient or use of opiate on the opiate. incidence of emesis. A search of the Zeneca database MEDLEY was undertaken and prospective randomized Keywords: inhalational agents, propofol; nausea, comparator studies identified. These were examined vomiting; meta-analysis. individually and independently by two of the authors

Background and objectiveThis open, multicentre study compared the ef®cacy and safety of remifentanil with fentanyl during balanced anaesthesia with 0.8% iso¯urane (end-tidal concentration) for major abdominal and gynaecological surgery, and the ef®cacy and safety of remifentanil for pain management in the immediate postoperative period. Methods Two-hundred and eighty-six patients were randomized to receive remifentanil 1 lg kg ±1 followed by 0.2 lg kg ±1 min ±1 (n 98), remifentanil 2 lg kg ±1 followed by 0.4 lg kg ±1 min ±1 (n 91) or fentanyl 3 lg kg ±1 (n 97) at induction. Thereafter, the study opioids and iso¯urane were titrated to effect during the operation. Results Compared with fentanyl, remifentanil 2 lg kg ±1 followed by 0.4 lg kg ±1 min ±1 reduced the incidence of response to tracheal intubation (30% vs. 13%, P < 0.01), skin incision (33% vs. 4%, P < 0.001) and skin closure (11% vs. 3%, P < 0.05), respectively. Patients receiving remifentanil 1 lg kg ±1 followed by 0.2 lg kg ±1 min ±1 had fewer responses to skin incision than the fentanyl group (12% vs. 33%, P < 0.001), but the incidences of response to tracheal intubation and skin closure were similar. Signi®cantly

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