This randomized controlled trial evaluates whether Integrated Pulmonary Index (IPI)-guided monitoring reduces oxygen desaturation and improves early detection of respiratory compromise during elective ERCP performed under standardized moderate sedation.

Adults undergoing elective ERCP are randomized 1:1 to standard monitoring alone or standard monitoring plus visible IPI (SpO₂, respiratory rate, pulse rate, and EtCO₂). Sedation is standardized (midazolam, fentanyl, ketamine) with a target RASS of -3 and routine supplemental oxygen. Oxygen desaturation (>5% decrease in SpO₂ from baseline) during the procedure is the primary outcome. Secondary outcomes include hypoxemia (SpO₂ <90%), apnea, bradypnea, and the frequency of airway interventions (verbal-tactile stimulation, jaw-thrust, head-tilt).

Inclusion Criteria:

• Age ≥18 years,
• Scheduled for elective ERCP,
• ASA physical status I-IV
• Ability to provide written informed consent

Exclusion Criteria:

• Age <18 years
• ASA physical status ≥V
• Pregnancy or suspected pregnancy
• Known allergy to study sedative agents
• Obstructive or restrictive pulmonary disease
• Pre-procedural supplemental oxygen therapy or non-invasive ventilation
• Predicted difficult airway
• Pre-procedural systolic blood pressure <90 mmHg
• Pre-procedural heart rate <60 beats/min
• Emergency ERCP

Parallel Assignment