Anesthesiologist-controlled versus patient-controlled propofol sedation for shockwave lithotripsy

Abstract

Purpose: To compare anesthesiologist-controlled sedation (ACS) with patient-controlled sedation (PCS), with respect to propofol requirements, sedation, and recovery, in patients undergoing extracorporeal shockwave lithotripsy for urinary calculi. Methods: Sixty-four patients were randomized, in this double-blind study, to receive propofol sedation according to one of two regimens: infusion of 200 μg·kg-1·min-1 for ten minutes reduced thereafter to 50-150 μg·kg-1·min-1 titrated by an anesthesiologist, according to patient response (group ACS), or propofol administered by patient-controlled analgesia (bolus dose 300 μg·kg-1, lockout interval three minutes, no basal infusion), (group PCS). All patients received midazolam 10 μg·kg-1 iv and fentanyl 1 μg·kg-1 iv preoperatively, followed by fentanyl infused at a rate of 0.5 μg·kg-1·hr-1 throughout the procedure. Sedation and analgesia were assessed using the A-line ARX index and visual analogue scale, respectively. Psychomotor recovery and readiness for recovery room discharge were assessed using the Trieger dot test and postanesthesia discharge score, respectively. Patient satisfaction was assessed on a seven-point scale (1-7). Results: In comparison to group PCS, patients in group ACS received more propofol (398 ± 162 mg vs 199 ± 68 mg, P < 0.001), were more sedated (A-line ARX index: 35 ± 16 vs 73 ± 16, P < 0.001), experienced less pain (visual analogue scale: 0 ± 0 vs 3 ± 1, P < 0.001), and were more satisfied (median [Q1, Q3]: 7 [7, 7] vs 6 [6, 7], P < 0.001). In contrast, patients in group PCS had faster psychomotor recovery (Trieger dot test median [Q1, Q3]: 8 [4, 16] vs 16 [12, 26] dots missed, P = 0.002) and achieved postanesthesia discharge score ≥ 9 earlier (median [Q1, Q3]: 40 [35, 60] vs 88 [75, 100] min, P < 0.001) compared with group ACS. Conclusion: In comparison to PCS for patients undergoing ext racorporeal shockwave lithotripsy, propofol/fentanyl ACS is associated with increased propofol administration, deeper sedation levels, and greater patient comfort. However, ACS is associated with slower recovery and a longer time to meet discharge criteria, when compared to PCS.