Effect of Lateral Versus Supine Positions on Postoperative Hypoxemia

Using prospective real-world data, this study aims to determine whether the lateral decubitus position reduces the incidence of post-procedure hypoxemia in patients undergoing painless gastroscopy/colonoscopy, thereby providing a simple, non-invasive, and low-cost optimization strategy for clinical practice.

Inclusion Criteria: 1. Age ≥ 18 years. 2. Both sexes. 3. American Society of Anesthesiologists (ASA) physical status classification I-III. 4. Scheduled for combined painless esophagogastroduodenoscopy/colonoscopy or either of the two procedures. 5. Ability to understand the study protocol and provide written informed consent. 6. A broad set of inclusion criteria was adopted to enroll a patient population that better reflects routine clinical practice. The study aimed to enhance the generalizability of the findings by including patients with various comorbidities, such as preprocedural hypoxemia (room-air SpO₂ ≤ 90%), history of pulmonary surgery, obstructive sleep apnea (OSA), and other pulmonary conditions (including asthma, COPD, chronic bronchitis, emphysema, and pulmonary bullae). Exclusion Criteria: 1. Severe cardiovascular or cerebrovascular diseases. 2. Pregnant patients. 3. History of hypersensitivity to ciprofol. Withdrawal Criteria: 1. Endotracheal intubation required during the procedure. 2. Voluntary withdrawal requested by the patient or their legal representative.