Patients undergoing urgent therapeutic ERCP for severe cholangitis, with American Society of Anaesthesiologist (ASA) Grade II - III. Will receive Ketofol (ketamine: propofol concentration 1:4) prepared in 50 ml syringe containing dextrose 5% (each ml contained 8 mg propofol and 2 mg ketamine), administered as following; 5 ml of ketofol as loading then infusion titrated till targeted RSS score.

Patients undergoing urgent therapeutic ERCP for severe cholangitis, with American Society of Anaesthesiologist (ASA) Grade II - III. Sedation was initially started by bolus dose of 0.5 mg/kg propofol IV over 3 minutes then, infusion was started at the rate of 50 µg /kg/min till RSS score of 5.

The level of sedation was assessed at 1-3 min intervals, and the infusion rate was adjusted accordingly to achieve a Ramsay Sedation Scale (RSS) score of 5. Any movement of the patient was treated by increasing infusion rate and the infusion was discontinued at the end of the procedure. The total propofol consumed was calculated and the recovery time was recorded and calculated as the time from discontinuation of infusion of the study drug till achievement of RSS score of 3. Then patients were discharged to post-anesthesia care unit (PACU) after attaining an Aldrete Recovery Scale Score of 9- 10 [19]. Time taken to achieve this score was also recorded.

The time to reach Ramsay Sedation Scale score of 5 to ensure adequate sedation. This scale is between 1-6.

The score 5 and 6 indicates adequate sedation while score <5 indicates inadequate sedation.

Heart rate (beats/min)

Pulse oximeter (SO2)