Dose Rate Range Finding Study of Propofol for minimal-to Moderate Sedation on Upper & Lower Endoscopic Tests

Infusion of placebo, same infusion rates as for arm 2

Infusion of propofol: initiation with 0.17 mg/kg for 3 minutes followed by maintenance with 25 µg/kg/minute

Infusion of propofol: initiation with 0.33 mg/kg for 3 minutes followed by maintenance with 50 µg/kg/minute

Infusion of propofol: initiation with 0.5 mg/kg for 3 minutes followed by maintenance with 75 µg/kg/minute

Infusion of propofol: initiation with 0.8 mg/kg for 3 minutes followed by maintenance with 120 µg/kg/minute

Infusion of propofol: initiation with 0.5 mg/kg for 1 minutes followed by maintenance with 75 µg/kg/minute

Infusion of propofol: initiation with 0.5 mg/kg for 5 minutes followed by maintenance with 75 µg/kg/minute