Patients were randomly divided into Dexmedetomidine or Ketofol for sedation. In patients who received Dexmedetomidine, a 2ml ampule of 100 ug/ml was diluted in 18 ml of normal saline, making a total volume of 20 ml. Patients received dexmedetomidine as a bolus over 10 minutes in a dose of 1ug/kg followed by an infusion at the rate of 0.5ug/kg/hr and it was labeled as "infusion 1". In the Ketofol group, 2 ml ketamine (50mg/ml) and 10 ml of propofol 1% (10mg/ml) were diluted in 8ml of normal saline. This mixture was 20 ml each, making 5mg/ml of ketamine and propofol. Patients received 1mg/kg over 10 minutes followed by 50ug/kg/min of infusion, labeled as "infusion 2".

Patients aged 20-60 years of any gender scheduled for elective ERCP were included. All these patients had American Society of Anesthesiologists (ASA) classification I or II. While those who were allergic to dexmedetomidine, Ketofol, or related medications, BMI over 36 kg/m2 (morbidly obese), had a history of stroke, renal impairment, chronic obstructive pulmonary disease, asthma, chronic liver disease, hypothyroidism, and congestive cardiac failure were excluded. Furthermore, pregnant, or breastfeeding women or patients who reported chronic use of sedative medications or substance abuse, known contraindications to ERCP, and already enrolled in another clinical trial study were excluded.

Patients were randomly divided into two groups using computer randomization. All patients were taken to the procedure room and venous access was secured on a non-dominant hand by 20G IV cannula, intravenous (I/V) fluid (ringer lactate or normal saline) was started by 8 ml/kg/h, and oxygen support was provided by nasal cannula at 4 liters per minute. Standard monitors were attached for heart rate (HR), noninvasive blood pressure (systolic and diastolic), mean arterial blood pressure (MAP), and peripheral oxygen saturation SpO2. Injection midazolam 0.05 mg/kg was also given I/V to every patient in both groups to decrease the anxiety of patients.

Patients received either Dexmedetomidine or Ketofol for sedation. All syringes and infusion sets were covered by silver paper and these infusions were labeled as infusion 1 or 2. In patients who received Dexmedetomidine, a 2ml ampule of 100 ug/ml was diluted in 18 ml of normal saline, making a total volume of 20 ml. Patients received dexmedetomidine as a bolus over 10 minutes in a dose of 1ug/kg followed by an infusion at the rate of 0.5ug/kg/hr and it was labeled as "infusion 1". In the Ketofol group, 2 ml ketamine (50mg/ml) and 10 ml of propofol 1% (10mg/ml) were diluted in 8ml of normal saline. This mixture was 20 ml each, making 5mg/ml of ketamine and propofol. Patients received 1mg/kg over 10 minutes followed by 50ug/kg/min of infusion, labeled as "infusion 2".

During infusion, vitals were recorded at 0,1,3,5, and 10-minute intervals from the start, and the Ramsay Sedation scale score (RSS) was recorded every 1 minute. Both infusions were started as per the randomization of groups. The mean difference in time to achieve adequate sedation and time to good recovery were noted as outcomes in each group. In addition, complications during the procedure and recovery were also noted. Adequate sedation was defined as the time from initiation of infusion to achieve an RSS score of 4. While Modified Aldrete's score (MAS) was used to assess the recovery. Time from discontinuation of the infusion to achieve an MAS score of 9 was labeled as a good recovery.

Inclusion Criteria:

• Aged 20-60 years
• Any gender
• Scheduled for elective ERCP
• American Society of Anesthesiologists (ASA) classification I or II

Exclusion Criteria:

• Allergic to dexmedetomidine, Ketofol, or related medications
• BMI over 36 kg/m2 (morbidly obese)
• History of stroke, renal impairment, chronic obstructive pulmonary disease, asthma, chronic liver disease, hypothyroidism, and congestive cardiac failure