High Flow Nasal Cannula in Patients Undergoing ERCP Retrograde Cholangiopancreatography With Intravenous Sedation.

The goal of this randomized clinical trial is to identify the optimal flow rate during high flow nasal cannula therapy that will prevent airway obstruction and its associated desaturation and maintain saturation greater than 95% in patients undergoing ERCP procedure under intravenous deep sedation. This study aims to identify the optimal flow rate during high flow nasal cannula therapy that will prevent airway obstruction and its associated desaturation and maintain saturation greater than 95% in patients undergoing ERCP procedure under intravenous deep sedation.

Participants will be randomized to 3 groups: G0 will receive a 5 l/ min flow rate through a nasal cannula at and FiO2 of 40 %, G1 will receive a 15 l/ min flow rate and FiO2 of 40% and G2: will receive a 60L/min flow rate and FiO2 of 40%.

Researchers will compare intraprocedural factors to find out the optimal nasal cannula flow rate for maintenance of safe IV deep sedation in endoscopic retrograde cholangiopancreatography (ERCP) patients and to assess gastroenterologist and patient satisfaction.

High flow nasal cannula provides adequate oxygenation in patients with compromised pulmonary function. Very few studies in the literature addressed its use with IV sedation in the OR. Successful application of High Flow nasal cannula in intravenous deep sedation cases in the OR will benefit in the reduction of airway manipulation and side effects from general anesthesia.

This study aims to find out the optimal nasal cannula flow rate for maintenance of safe IV deep sedation in endoscopic retrograde cholangiopancreatography (ERCP) patients and to assess gastroenterologist and patient satisfaction.

A total of 60 patients undergoing ERCP will be equally randomized to 3 groups:

G0: will receive a 5 l/ min flow rate through a nasal cannula at and FiO2 of 40 %, G1: will receive a 15 l/ min flow rate and FiO2 of 40% and G2: will receive a 60L/min flow rate and FiO2 of 40%. The anesthesia resident assigned to the case and the gastroenterologist will be blinded except for the attending anesthesiologist in- charge for setting the high flows according to groups. Mean age, weight, height and BMI of participants in the different groups will be calculated. SpO2, incidence and frequency of snoring,ETCO2 and gastroenterologist satisfaction scores will be recorded in the different groups. Drop in SpO2 saturation to less than 93%, snoring, and gastroenterologist dissatisfaction during the procedure will require to cross over patients to another group.

The three groups' intra-procedure and outcome parameters and variables will be compared. Statistical comparison will be made using the ANOVA, Student's t-test, and Chi-squared test. Level of statistical significance will be considered at p\<0.05. ANOVA test will be performed to compare the different means between the four groups. Minimum and maximum 3 of 17 values will be recorded for each value in all 3 groups. A two sided P value of less than 0.05 will be considered statistically significant.

The study will show the optimal oxygenation/ventilation management strategy with high flow nasal cannula for safety and satisfaction of patients undergoing ERCP with intravenous sedation, thus avoiding the general anesthesia's risks and post-procedure side effects.

Eligibility Criteria:
Inclusion Criteria:

1. Patient able to give consent.
2. Patient undergoing deep sedation.
3. Patient undergoing ERCP procedure with no restrictions on the duration of the procedure.
4. Age \> 18 years
5. Patients with BMI \< 40 kg/m2

Exclusion Criteria:

1. Patient unable to give consent
2. Patient refusal to participate
3. Patients undergoing general anesthesia
4. age less than 18 years old
5. Patients with severe heart failure (EF\<30%)
6. Morbidly obese Patients with BMI \> 40 kg/m2
7. Patients with sleep apnea
8. Claustrophobia
9. Risk of aspiration due to severe reflux
10. Facial injury, facial malformation
11. Nasal defects/obstruction
12. ASA 4 patients