Comparison between Low Flow and High Flow Sevoflurane Isocapnic Technique to Achieve Early Recovery after Surgery (ERAS)

Objective: the purpose of this study was to compare recovery time between low flow and high flow sevoflurane isocapnic anesthesia techniques, as well as the total consumption of sevoflurane. Design: This study was an observational single-blind randomized trial setting Operating room. Patients: Total 40 patients from gender, 18 to 60 years old, BMI 18.5-29.99 kg/m 2 with physical status ASA I or II, that scheduled for elective surgery under general anesthesia approximately between 3-5 hours were selected for this study. Intervention Selected patients divided randomly into two groups (n=20 each). First group was given low flow sevoflurane, delivered with initial flow 6 L/min until MAC 0.9 or expiration level of sevoflurane 2.2 vol% then reduced flow to 0.5 L/min; second group with high flow technique 4L/min after induction. Measurement The duration of operation, duration of anesthesia, time reaching of BIS 75, eye- opening with command, extubation, moving into the recovery room and when reaching Modified Aldrete score 10. Main Results: Based on statistics, sample characteristics, hemodynamic conditions, length of anesthesia and number of fentanyl were not significantly different. There was a significant difference on post anesthesia recovery time between low flow and high flow anesthesia time BIS 75: 1.7 (± 0.801) vs 7.05 (± 3.956), p<0.001, eye-opening time: 5.45 (± 3.82) vs. 14.86 (± 7.945 ), p<0.001, extubation time: 5.8 (± 2.783) vs. 15.29 (± 8.776), p<0.001, moving into recovery room: 15.35 (± 5.133) vs. 23.52 (± 12.213), p=0.021, time reaching modified aldrete 10: 8.95 (± 4.211) vs. 29 (± 18,091), p<0.001). Conclusion: Recovery time after general anesthesia using low flow sevoflurane isocapnic anesthesia technique is faster than the high flow anesthesia technique with less sevoflurane consumption.