Background: This study aimed to determine the potential advantages of midazolam co-induction with general anesthesia (GA) over the use of propofol alone.Methods: We conducted a randomized, placebo-controlled, single-blinded clinical trial of 102 patients, aged 18 to 65, American Society of Anesthesiologists II and III, who underwent elective laparoscopic gallbladder surgery. Patients were randomly divided into 3 groups: the placebo group (C) received 1 mL of 0.9% saline intravenously and the test groups received intravenous midazolam at doses of 0.03 mg/kg (M1) or 0.06 mg/kg (M2) before induction of GA. We assessed effects of midazolam co-induction on arterial pressure and heart rate (HR) in the early stage of GA prior to surgical incision and effects on perioperative and postoperative glycemia and cortisol levels. Systolic/mean/diastolic (SAP/MAP/DAP) arterial pressure and HR were measured 4 times (preoperative, on the third, sixth and ninth minute after atracurium administration). Cortisol was measured on 3 occasions (preoperatively, 60 minutes after surgical incision, and the following morning) and glucose on 4 occasions (preoperatively, 15 and 60 minutes after incision, and the following morning). We also assessed the incidence of postoperative anxiety, postoperative nausea and vomiting (PONV), and propofol requirement for induction.Results: SAP/MAP/DAP were significantly higher in M2 immediately after induction compared to the other study groups (P = .002/.004/.013). Midazolam co-induction led to a significant reduction in postoperative anxiety (P = .03), reduced cortisol concentration 60 minutes after surgical incision (P < .001) and propofol requirements (P < .001).
Conclusion subsections:Midazolam co-induction prevented a marked decline in SAP/MAP/DAP immediately after induction of GA, led to reduced postoperative anxiety and cortisol response to surgery, and reduced propofol requirements for induction.Abbreviations: BIS = bispectral index monitoring, C = placebo/control group of patients, COR = cortisol, GA = general anesthesia, GLU = glucose, HR = heart rate, M1 = group of patients that received intravenous midazolam at dose of 0.03 mg/ kg, M2 = group of patients that received intravenous midazolam at dose of 0.06 mg/kg, MAC = minimum alveolar concentration, PONV = postoperative nausea and vomiting, SAP/MAP/DAP = systolic/mean/diastolic blood pressure, SAS = Zung's Self-rating Anxiety Scale, TIVA = total intravenous anesthesia.
