[Pharmacoeconomical model for cost calculation using a study on prophylaxis of nausea and vomiting in the postoperative phase as an example. Cost effectiveness analysis of a tropisetron supplemented desflurane anaesthesia in comparison to a propofol total intravenous anaesthesia (TIVA)].

AIM OF THE STUDY: Postoperative nausea and vomiting (PONV) are among the most frequent complications after general anaesthesia. Avoiding these symptoms is of utmost importance for most patients; PONV is not only a major source of discomfort for patients but also a cause of additional costs for the patients and the health care provider. The economical impact of PONV will become even more important in the near future because the number of surgical procedures performed on an ambulatory basis is increasing. The following article gives a short overview of the terminology and measures used in pharmacoeconomical studies concerning PONV. Furthermore the economical aspects of a low-flow anaesthesia supplemented with the 5-HT(3)-antagonist tropisetron compared with a total intravenous anaesthesia (TIVA) using propofol are described.

METHODS: For this comparison a decision analysis was performed using data of a randomised control trial on 150 female patients undergoing major gynaecological surgery. The patients were randomised to receive a total intravenous anaesthesia with propofol-alfentanil or a balanced anaesthesia with desfluran (fresh gas flow 1 l.min(-1)) supplemented by 2 mg tropisetron at the end of surgery.

RESULTS: Indirect costs associated with anaesthesia using desflurane-tropisetron (4.94 Euro) are not different from that of propofol-TIVA (4.81 Euro) because of a similar incidence of PONV in the PACU. Furthermore, the total cost for 100 min general anaesthesia is higher in the desflurane-tropisetron group (30.94 Euro) compared with the TIVA group (24.55 Euro) due to the decreasing acquisition costs of propofol in the last 2 years.

CONCLUSION: Total intravenous anaesthesia with propofol is more cost-efficient than balanced anaesthesia with desflurane and additional tropisetron as a prophylactic antiemetic.