Comparison of 2 effect-site concentrations of remifentanil with midazolam during transrectal ultrasound-guided prostate biopsy under procedural analgesia and sedation: A randomized controlled study

Abstract

Background: Until now, target-controlled infusion of remifentanil with midazolam for transrectal ultrasound-guided prostate biopsy has not been described. Here, we investigate 2 effect-site concentrations of remifentanil with intermittent bolus midazolam for transrectal ultrasound-guided prostate biopsy under procedural analgesia and sedation.Methods: A prospective, randomized controlled trial including patients who received a transrectal ultrasound-guided prostate biopsy between February 2019 and January 2021 was conducted. Group 1 and Group 2 were respectively administered an initial effect-site concentration of remifentanil of 1.0 ng/mL and 2.0 ng/mL by a target-controlled infusion pump with Minto model. In both groups, maintenance of the effect-site concentration of remifentanil was adjusted upward and downward by 0.5 ng/mL to keep patient comfort with acceptable pain (remaining moveless), and mean arterial pressure and heart rate within baseline levels ± 30%, and using intermittent bolus midazolam to keep the Observer's Assessment of Alertness/Sedation scale between 2 and 4. The primary outcome was to determine which effect-site concentration of remifentanil provide adequate patient comfort with acceptable pain (remaining moveless) during the procedure.Results: A total of 40 patients in Group 1 and 40 patients in Group 2 were eligible for analysis. Most parameters were insignificantly different between Group 1 and Group 2, except Group 1 having higher peripheral oxygen saturation while probe insertion compared with Group 2. Group 2 patients had less intraoperative movements affecting the procedure (2 vs 18; P < .001), and less total times of target-controlled infusion pump adjustment (0 [0-1] vs 1 [0-3], P < .001) compared with group 1. However, group 1 patients had less apnea with desaturation (peripheral oxygen saturation < 90%; 0 vs 9, P = .002) and less remifentanil consumption (94.9 ± 25.5 μg vs 106.2 ± 21.2 μg, P = .034) compared to Group 2. Conclusion:In transrectal ultrasound-guided prostate biopsy, target-controlled infusion with remifentanil Minto model target 2.0 ng/ mL with 3 to 4 mg midazolam use provided sufficient analgesia and sedation, and appropriate hemodynamic and respiratory conditions.Abbreviations: ANI = analgesia nociception index, BIS = bispectral index, Ce = effect-site concentration, EtCO 2 = endtidal carbon dioxide pressure, HR = heart rate, MAP = mean arterial pressure, OAA/S = Observer's Assessment of Alertness/ Sedation, PACU = postanesthesia care unit, PAS = procedural analgesia and sedation, PNB = periprostatic nerve block, PONV = postoperative nausea and vomiting, REMI = remifentanil, SBP = systolic blood pressure, SpO 2 = peripheral oxygen saturation, TCI = target-controlled infusion, TRUS = transrectal ultrasound, TSGH = Tri-Service General Hospital.