Background: Nonanesthesiologist-administered propofol (NAAP) is controversial due to deep sedation concerns.
Aim: The purpose of this study was to evaluate the feasibility of moderate sedation with two different NAAP regimens for colonoscopy.
Methods: This was a double-blinded, randomised, placebo-controlled trial allocating 135 consecutive outpatients to placebo (group P) or midazolam 2 mg (group M+P) before NAAP targeted to moderate sedation. Depth of sedation every 2 min throughout the procedure, propofol doses, recovery times, complications and patient and endoscopist satisfaction were measured.
Results: A total of 84 % of assessments of the depth of sedation were moderate. Mean induction (76 [40-150] vs. 53 [30-90]) and total propofol doses (mg) (136 [60-270] vs. 104 [50-190]) were significantly higher for group P (p < 0.001). However, deep sedation was significantly more prevalent in group M+P in minutes 4 (16 vs. 1 %, p = 0.05), 6 (20 vs. 3.5 %, p = 0.046) and 8 (17 vs. 1.8 %, p = 0.06) of the procedure, coinciding with midazolam peak action. From minute 8 on, moderate sedation was significantly deeper for M+P (p = 0.002). Early recovery time (6.8 min vs. 5.2, p = 0.007), but not discharge time (10.4 min vs. 9.8, p = 0.5), was longer for M+P. Pain perception (P 1.03 vs. M+P 0.3, p = 0.009) and patient satisfaction scores (P 9.4 vs. M+P 9.8, p = 0.047) were better for M+P. No major complications occurred.
Conclusions: Moderate sedation was feasible with both NAAP regimens. Drug synergy in the midazolam plus propofol sedation regimen promotes a deeper and longer moderate sedation, improving patient satisfaction rates but prolonging early recovery time (Clinical Trials gov NCT01428882).