Materials and methods
mental illness, substance abuse
MAY
This was a prospective, randomized, parallel-group clinical trial. This study was conducted between 27 May 2022 and 17 August 2022 in the IVF unit. The protocol was registered on the One hundred and thirty American Society of Anesthesiologist’s Class I or II patients, over age 18, undergoing transvaginal oocyte retrieval for in vitro fertilization under general anesthesia were included in this study. Patients were excluded if they had contraindication for general anesthesia, they had a history of mental illness, alcohol, or substance abuse. Patients were randomized into two groups (65 patients in group bolus, 65 patients in group BIS) by an anesthesiologist who was not included in the study. Randomization was performed by opening one of a series of sequentially numbered opaque envelopes that contained the group assignment. Written informed consent was obtained from all study participants. The patients, and the gynecologist were blinded to group assignment.Each patient’s age, weight, height, body mass index (BMI), and ASA classification were recorded preoperatively. All the patients fasted for at least 6 h prior the procedure and did not receive premedication. On the arrival in the operating room, heart rate, noninvasive blood pressure, and oxygen saturation on pulse oximetry were monitored, an intravenous canula was inserted and 0.9% sodium chloride (NaCl) infusion was started. Patients in group BIS were also monitored with BIS.In both groups, anesthesia was induced with intravenous propofol (2 mg/kg) and fentanyl (2 μg/kg) administration. A second-generation laryngeal mask was inserted two minutes after the anesthesia induction in group bolus and when BIS value < 60 in group BIS. Normocapnic mechanical ventilation was initiated. A 40% oxygen/air mixture was used during the procedure. Laryngeal mask placement was attempted 2 times, if unsuccessful, ventilation with face mask was continued, and the patient was excluded from the study. The number of insertion attempts was recorded.In group bolus, 0.5 mg/kg propofol was administered when the intraoperative movement scale (IOMs) was ≥ 2.