Background: The aim of this investigation was to compare routine balanced anaesthesia with different inhalation agents to intravenous anaesthesia (IVA) using an Anaesthesia-Information-Management-System (AIMS) with regard to time of recovery from anaesthesia, the time of discharge from the postanaesthesia care unit (PACU) and postoperative nausea as well as postoperative therapy with analgesics.
Methods: In 1997 and 1998 all relevant data of each anaesthesia procedure have been recorded using the online documentation Software NarkoData. These data sets have been stored into a relational database during each anaesthesia procedure. For evaluation the information has been exported from the database to a statistics program via 'Structured Query Langvage' (SOL). Balanced anaesthesia has been performed using isoflurane, halothane, and sevoflurane, respectively, supplemented with or without nitrous Oxide (N2O). The intravenous based anaesthesia-groups included propofol-fentanyl or propofol-remifentanil.
Results: The fastest recovery was seen in patients of the isoflurane group (11.2 +/- 7.7 minutes), and the longest time for extubation was observed in patients wich halothane anaesthesia (12.8 +/- 9.3 minutes); the overall mean difference was 1.7 minutes. The earliest patient admitted to the PACU had received sevoflurane (7.0 +/- 6.3 minutes) and propofol-remifentanil (7.0 +/- 7.4 minutes) whereas patients of the halothane group (9.5 +/- 7.5 minutes) took more. The shortest stay in PACU was seen in patients of the sevoflurane and isoflurane groups (105.13 +/- 35.7 and 108.4 +/- 60.5 minutes), whereas propofol-remifentanil (126.2 +/- 89.1 minutes) and halothan (120.0 +/- 86.1 minutes) anaesthetised patients had the longest stay in PACU. No difference was noted in the incidence of postoperative nausea and vomiting nor in the amount of postoperatively given analgesics.
Conclusion: Results achieved in routine correspond only in part to results from studies. In our investigation balanced anaesthesia with isoflurane and sevoflurane correspond with the shortest stay in PACU compared to balanced anaesthesia with halothane and IVAs with propofol-fentanyl or propofol-remifentanil. One reason for this could be the intraoperatively administered opioide piritramide in IVAs. Furthermore we conclude that an AIMS may provide additional information about overall costs-effectiveness. However this information depends largely on local factors, e.g. patient case mix, staffing, policy of discharge from the PACU etc.