Conscious sedation for gastroscopy: Patient tolerance and cardiorespiratory parameters

Background/Aims : Most patients receive conscious sedation for gastroscopy. However, the benefit of the most often used combination of low-dose intravenous midazolam and topical lidocaine on patient tolerance remains poorly defined and has not been shown to outweigh cardiorespiratory risks. To respond to these issues, a randomized, double-blind, placebo-controlled prospective study was performed. Methods : Two hundred outpatients undergoing diagnostic gastroscopy were assigned to receive either (1) midazolam (35 μg/kg) and lidocaine spray (100 mg), (2) midazolam and placebo lidocaine, (3) placebo midazolam and lidocaine, or (4) placebo midazolam and placebo lidocaine. Results : Tolerance (visual analogue scale, 0–100 points; 0, excellent; 100, unbearable) improved as compared with placebo midazolam and placebo lidocaine by 23 points (95% confidence interval, 15–32) in group 1, 15 points (95% confidence interval, 7–24) in group 2, and 10 points (95% confidence interval, 2–18) in group 3. Increasing age ( P < 0.001), low anxiety ( P < 0.001), and male sex ( P < 0.03), but not amnesia, were associated with better patient tolerance. Oxygen desaturation (