Effectiveness of bispectral index on clinical outcomes of beating heart off-pump coronary artery bypass grafting surgeries

Background: In high-risk patients with low hemodynamic reserve, it can be challenging to get the optimal level of anesthesia without awareness during off-pump coronary artery bypass grafting (OP-CABG) surgeries. This study aimed to test whether the use of bispectral (BIS) Index monitoring reduces the anesthetic requirements and improves the clinical outcomes during beating heart CABG without awareness during general anesthesia (ADGA). Materials and Methods: This study was a single-center, prospective, randomized clinical comparative study on the American Society of Anesthesiologists (ASA) three patients booked for elective beating heart OP-CABG surgeries under general anesthesia (GA). Patients received sevoflurane anesthesia for the maintenance of anesthesia, and their consumption was calculated and compared between study groups. The control groups received conventional sevoflurane anesthesia, and hemodynamic parameters (±20% of initial values) were considered for anesthesia. The study groups received sevoflurane, and BIS (value 45 ± 5) was used to maintain anesthesia. In the study group, keeping the BIS monitor screen open, and the anesthesia needs were set. However, in the control group, the monitor screen was closed in such a way that the anesthetist could not see the BIS value. In addition, hemodynamic parameters, awakening conditions, length of intubation, inotropic requirements, cardiac care unit (CCU), and hospital stay were recorded. To explicit ADGA, patients were interviewed 24 h after extubation. Results: The sevoflurane was used at 59.81 ± 13.87 mL in the control group and 31.47 ± 7.91 mL in the study group, with a 47% reduction in requirement. This difference was statistically significantly low with BIS-monitored anesthesia in the study group compared to conventional anesthesia in the control group. The number of cases in which adrenaline was used was 94.87% in the control group and 53.65% in the study group. On calculating, there was a reduction of 54.80% in adrenaline requirement with BIS-monitored anesthesia compared to conventional anesthesia, and this difference was statistically significant. In control and study groups, the lengths of endotracheal intubation were 3.50 ± 4.72 and 2.17 ± 1.36 h, respectively. The intubation time was reduced by 40% with BIS, which was statistically significantly lower for the BIS groups ( P < 0.05). Conclusion: BIS monitoring reduces the anesthetic drug sevoflurane requirement by 47% in patients undergoing OP-CABG surgeries without ADGA on a BIS level of 45 ± 5. There was a reduction of 54.80% in adrenaline requirement and 40% in intubation time with the BIS monitoring, which culminated in ultra-fast track extubation in high-risk patients undergoing beating heart OP-CABG surgeries.