Substitution of Isoflurane by Sevoflurane Toward the End of Long Surgeries Is Cost Effective

The lower solubility of sevoflurane allows a more rapid emergence from anesthesia than after anesthesia with more soluble but less expensive anesthetic isoflurane. Cost control in anesthesia is no longer an option; it is a necessity. We substitute sevoflurane for isoflurane toward the end of anesthesia for operations longer than 3 hours in an attempt to combine the cost effectiveness of isoflurane with rapid emergence from sevoflurane. Sixty patients undergoing long abdominoplastic and ENT surgeries were randomly equally divided into three groups: group I (isoflurane group), group II (crossover group) where isoflurane was substituted by sevoflurane during the last 30 minutes of the operation and group III (sevoflurane group). A fresh gas flow of 2 L/min as 60% N2O in O2 was used for maintenance of anesthesia. Consumption of volatile anesthetics was measured by weighing the vaporizers with a precision weighing machine and recovery variables were recorded. The times for spontaneous breathing, times to opening eyes, squeeze a finger on command, times for extubation, orientation, times to read Aldrete score > 9 and time to discharge from PACU, all these times were significantly longer in isoflurane group than the crossover and sevoflurane groups and no significant difference between crossover and isoflurane groups. Cost was significantly higher in sevoflurane group (1.242 EP per minute anesthesia). The costs among the other two groups did not differ significantly (0.319 EP/min for isoflurane group and 0.344 EP/min for crossover group). So sevoflurane based anesthesia was associated with the highest costs and faster recovery. In conclusion, by changing from isoflurane to sevoflurane toward the end of long anesthesia, we can accelerate recovery and decrease its expenditures without compromising the measured patient outcomes.