After approval of ethical committee of Sindh Institute of Urology & Transplantation (SIUT), 86 patients were enrolled for the elective endoscopic retrograde cholangiopancreatography (ERCP). Randomization was done by a computer-generated randomization table. Patients were divided in two groups based on agents used for the research study. Both the groups were induced by injection midazolam 0.06 mg/kg body weight and injection nalbuphine 0.1 mg/kg body weight. In group A, anesthesia was maintained by Sevoflurane inhalation via nasal prongs with oxygen to achieve minimum alveolar concentration (MAC) approximately 0.25%. Whereas, in Group B propofol infusion at 50 ug/Kg/min started for maintenance of anaesthesia. Ketamine 0.5mg/kg intravenously was used to rescue the sedation level in both groups

After approval of ethical committee of SIUT, 86 patients were enrolled for the elective endoscopic retrograde cholangiopancreatography (ERCP). Pre-operative assessment was done by history of patients, general physical examination, systematic examination, and laboratory investigations. Randomization was done by a computer-generated randomization table. Patients were divided in two groups based on agents used for the research study. Both the groups were induced by injection midazolam 0.06 mg/kg body weight and injection nalbuphine 0.1 mg/kg body weight. In group A, anesthesia was maintained by Sevoflurane inhalation via nasal prongs with oxygen to achieve minimum alveolar concentration (MAC) approximately 0.25%. Whereas, in Group B propofol infusion at 50 ug/Kilogram/min started for maintenance of anaesthesia.

When Ramsay Sedation Scale 5 is achieved then the endoscopist was allowed to insert endoscope. Injection Ketamine 0.5 mg/kg body weight was used for rescue sedation level. Upon arrival in operation theatre standard monitoring which includes pulse oximeter (SPO2), noninvasive blood pressure (NIBP), electrocardiogram (ECG) electrodes were applied, and baseline readings will be recorded. After that venous access was secured on a non-dominant hand by 20 Gauge IV cannula. Ringer's lactate or normal saline was then started at 8 ml/kg/hour and O2 was given by nasal prongs at 4 L/min. All baseline parameters were taken, after that readings were taken at 5 min, 10 min, 15 min, 20 min and so on till procedure ends.

Complications such as respiratory depression, coughing, gagging, nausea and vomiting were recorded during the procedure and treated accordingly. If SpO2 went down below 92% for more than 10 seconds or patient developed apnea, it was considered oxygen desaturation.

Oxygen desaturation was managed by O2 inhalation and supporting airway. A heart rate under 40 beats per minute was considered bradycardia and it will be managed by inj Atropine 10 ug/Kilogram intravenously (I/V). Mean arterial pressures level that is lower than 60 mmHg or 20% less than the baseline was regarded as hypotension and it was managed by fluid bolus or vasopressors.

After the procedure, patients were awakened and shifted to recovery room. Complications such as respiratory depression, coughing, gagging, nausea and vomiting were recorded and treated accordingly.

Inclusion Criteria:

• Patients between age group of 20-60 years
• Both male and female patients.
• American Society of Anesthesiologist (ASA) physical status I-II
• Elective ERCP procedure.

Exclusion Criteria:

• Patients allergic to any study drug.
• American Society of Anesthesiology (ASA) Physical status III-IV
• Patients with uncontrolled Diabetes Mellitus,
• Hypertension and renal insufficiency.
• Body mass index (BMI) over 36 Kilogram/m2 (Morbid obesity)
• Obstructive Sleep Apnea
• Gastroesophageal reflux disease (GERD)
• Pregnancy