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Background: In the present investigation we compared the consumption of desflurane (DES) and isoflurane (ISO) using a standardized minimal-flow protocol with a forced reduction of the fresh gas flow (FGF)., Methods: 54 adult women were examined. After induction of anaesthesia a forced reduction of the FGF was started: 5 min 0.5 l/min O(2) + 1 l/min N(2)O, 10 min 0.5 l/min O(2) + 0.5 l/min N(2)O; finally 0.3 l/min O(2) + 0.2 l/min N(2)O up to the end of surgery. The consumption of DES/ISO was determined with a precision balance., Results: In the DES group the uptake was around 0.3 vol-%, i.e. less than 8% of the target 2/3 MAC value was taken up. For ISO the uptake was around 0.25 vol-%, i.e. the uptake was approximately 30% of the target 2/3-MAC value. The DES consumption was after 60 min 17.0+/-1.1 g, 120 min--27.3+/-1.8 g and 180 min--36.5+/-1.7 g. ISO consumption was significantly lower: 7.6+/-0.8 g, 12.4+/-1.7 g and 15.5+/-1.6 g. The use of DES yielded higher costs, i.e. 2.28 EUR for 60 min, 3.63 EUR for 120 min and 4.97 EUR for 180 min. The consumption of the inhaled anaesthetics can be calculated as: DES (g)=4.84+0.184 x duration (min) (R(2)=0.981), ISO (g)=2.049+0.0826 x duration (R(2)=0.979). The costs are: DES (EUR)=0.85+0.0323 x duration (min); ISO (EUR)=0.19+0.0077 x duration (min)., Conclusion: With a forced reduction of the FGF the DES consumption is still higher.

Reduction of the perioperative cardiovascular risk with pharmacological interventions plays a prominent role in routine anesthesia practice. For example, perioperative beta-blockade is well established in anesthesiological treatment of patients. There is a growing body of evidence supporting the cardioprotective effects of volatile anesthetics known as anesthetic-induced preconditioning. There are numerous and complex data from animal studies. The mechanisms of anesthetic-induced preconditioning have been extensively studied but have still not been clearly identified. Initial clinical data show the cardioprotective effects of volatile agents by looking at parameters of myocardial function and laboratory values and therefore, the question of the relevance of these data for routine clinical practice has been raised. This review gives a summary of the currently available data focusing on the mechanisms of anesthesiological preconditioning and clinical studies.

Introduction: We investigated gender differences of drug consumption and recovery times for propofol-remifentanil anaesthesia., Methods: Adult patients scheduled for minor orthopaedic surgery were randomised to receive a propofol-remifentanil anaesthesia controlled either by EEG monitoring (Narcotrend or BIS) or solely by clinical parameters. Anaesthesia was induced with remifentanil 0.4 microg/kg/min and a propofol target-controlled infusion (TCI) at 3.5 microg/ml. After intubation remifentanil was reduced to 0.2 microg/kg/min whereas propofol TCI was adjusted according to clinical parameters or to the following EEG target values: during maintenance to "D(0)" (Narcotrend) or "50" (BIS), 15 min before the end of surgery to "C(1)" (Narcotrend) or "60" (BIS). Recovery times were recorded and average normalised propofol consumption was calculated from induction and maintenance doses., Results: A total of 60 male and 60 female patients completed the study. Gender differences were observed for recovery times (with standard practice) and for propofol consumption (with BIS monitoring). In the standard protocol group, propofol consumption was nearly identical for male and female patients whereas recovery times were significantly longer in the male group. In both EEG-guided groups propofol consumption was less for male patients while recovery times were slightly longer. In the group of female patients higher propofol TCI concentrations had to be used to reach the same BIS or Narcotrend values., Conclusion: With propofol-remifentanil anaesthesia, gender has impact on recovery times and propofol consumption. If the same amounts of propofol are applied, males awake later, with BIS or Narcotrend monitoring males receive less propofol for comparable EEG effects.