Comparison of Safety and Efficacy for Different Sedation Regimens During Colonoscopy

The study will involve 157 patients who meet the inclusion criteria and are scheduled for elective colonoscopy. Sample size is calculated by ANOVA F test. Participants will be randomly assigned into three groups using computer-based randomization. Group I will receive intravenous midazolam + fentanyl, Group II will receive propofol only, and Group III will receive fentanyl + propofol. Dosages will be titrated as needed during the procedure, with sedation administered by trained nurses/doctors under the supervision of an anesthesiologist to ensure patient safety. Experienced endoscopists will perform the procedures, and all participants will undergo a pre-procedure evaluation, including medical history, physical examination, and assessment of allergies, comorbidities, and ASA classification. Data on patient demographics, procedure details, and sedative dosages will be collected, alongside monitoring of vital signs, oxygen saturation, and blood pressure before, during, and after the procedure. The primary outcomes for the study include the degree of sedation, onset of sedation, patient satisfaction, and procedure completion rate. The degree of sedation will be assessed using the Observer's Assessment of Alertness/Sedation (OAA/S) scale, while the onset of sedation will be defined as the time it takes for the patient to show drowsiness and reduced responsiveness. Secondary outcomes include adverse events, recovery time, and endoscopist satisfaction. Adverse events, such as hypotension, tachycardia, bradycardia, and hypoxia, will be recorded using pre-defined criteria for each. Recovery will be assessed every 10 minutes post-procedure using the Aldrete score, with a score of 10 indicating full recovery, after which patients can be discharged. Both patient and endoscopist satisfaction will be measured on a scale of 0 to 5 using Likert scale. This comprehensive approach aims to determine the efficacy, safety, and patient/endoscopist experience associated with the three sedative regimens during colonoscopy