Comparison between the effect of bispectral index and minimum alveolar concentration monitoring on recovery after general anesthesia: a prospective, randomized, clinical study

Abstract

Introduction: Early extubation and fast recovery are important to increase the efficiency of health care services, reduce morbidity, and reduce the burden of health care costs. This study was conducted to investigate the effect of bispectral index (BIS) monitoring compared to the minimum alveolar anesthetic concentration (MAC) monitoring on recovery of patients undergoing isoflurane-based general anesthesia. Materials and Methods: A total of 62 patients were randomly allocated to group B (BIS-guided) and group M (MAC-guided). Along with clinical hemodynamic monitoring for titration of isoflurane in group B, BIS was monitored and maintained between 40 and 60, whereas in group M, MAC was maintained between 0.7 and 1.3. The recovery profile was studied in terms of time to eye-opening, time to extubation, and time to achieve the modified Aldrete score ≥9 in both groups. Patients were followed up for any postoperative side effects and awareness during general anesthesia. Results: Group B and group M were comparable with respect to age, gender, duration of surgery, duration of anesthesia, and type of surgery. Median time to eye-opening was 4 min in group B and 5 min in group M (P < 0.001). The time to extubation was 8 min in group B, compared to 11 min in group M (P < 0.001). Furthermore, the time needed to achieve the modified Aldrete’s score of ≥9 was also shorter in group B (P < 0.001). No patients reported awareness during anesthesia. Conclusion: The use of BIS monitoring hastens the extubation and recovery in patients undergoing general anesthesia.

Keywords

• anesthesia recovery
• bispectral index
• depth of anesthesia monitors
• extubation time
• isoflurane
• minimum alveolar concentration