Dose requirement and complications of diluted and undiluted propofol for deep sedation in endoscopic retrograde cholangiopancreatography

BACKGROUND: In general, the dose requirement and complications of propofol are lower when used in the diluted form than in the undiluted form. The aim of this study was to determine the dose requirement and complications of diluted and undiluted propofol for deep sedation in endoscopic retrograde cholangiopancreatography. METHODS: Eighty-six patients were randomly assigned to either group D (diluted propofol) or U (undiluted propofol). All patients were sedated with 0.02-0.03 mg/kg midazolam (total dose <= 2 mg for age <70 years and 1 mg for age >= 70) and 0.5-1 mu g/kg fentanyl (total dose <= 75 mu g for age <70 and <= 50 mu g for age >= 70). Patients in group U (42) were sedated with standard undiluted propofol (10 mg/mL). Patients in group D (44) were sedated with diluted propofol (5 mg/mL). All patients in both groups were monitored for the depth of sedation using the Narcotrend system. The primary outcome variable was the total dose of propofol used during the procedure. The secondary outcome variables were complications during and immediately after the procedure, and recovery time. RESULTS: All endoscopies were completed successfully. Mean propofol doses per body weight and per body weight per hour in groups D and U were 3.0 mg/kg, 6.2 mg/kg per hour and 4.7 mg/kg, 8.0 mg/kg per hour, respectively. The mean dose of propofol, expressed as total dose, dose/kg or dose/kg per hour and the recovery time were not significantly different between the two groups. Sedation-related adverse events during and immediately after the procedure were higher in group U (42.9%) than in group D (18.2%) (P=0.013). CONCLUSIONS: Propofol requirement and recovery time in the diluted and undiluted propofol groups were comparable. However, the sedation-related hypotension was significantly lower in the diluted group than the undiluted group.