Predictive value of the STOP-Bang Questionnaire for respiratory depression risk in patients undergoing painless gastrointestinal endoscopy.

Background: Obstructive sleep apnea (OSA) is an independent risk factor for perioperative respiratory complications. The STOP-Bang Questionnaire (SBQ) is a widely used screening tool; however, its utility in predicting respiratory depression during deep sedation for gastrointestinal endoscopy warrants further exploration. This study aimed to evaluate the predictive performance of the SBQ for respiratory depression in this patient population.

Methods: This prospective observational cohort study enrolled patients who underwent esophagogastroduodenoscopy (EGD) and colonoscopy under deep sedation at Dongguan Binhaiwan Central Hospital from November 2024 to February of the following year. The data collected included demographics, medical history, vital signs, and SBQ scores. Standard sedation monitoring was complemented by portable sleep monitoring systems to record the Apnea-Hypopnea Index (AHI). Patients were grouped based on their lowest intraoperative pulse oximetry (SpO₂) level. Spearman correlation, Kappa test, Receiver Operating Characteristic (ROC) curve analysis, and binary logistic regression were used to analyze the relationships between SBQ scores, AHI, and respiratory depression events.

Results: Data of 349 patients were included in the final analysis. Transient hypoxemia (SpO₂ < 90%) occurred in 65 (18.6%) patients, with 12 (3.4%) patients experiencing severe hypoxemia (SpO₂ < 80%). Both SBQ scores and AHI demonstrated significant negative correlations with SpO₂ levels (r = -0.520 and r = -0.737, respectively; both P < 0.001). Using SpO₂ < 85% as the threshold, the Area Under the ROC Curve (AUC) for the SBQ score was 0.942. The optimal SBQ cutoff value was 2.5, yielding a sensitivity of 0.871 and a specificity of 0.912. Logistic regression identified snoring (OR = 14.240), observed apnea (OR = 7.092), and elevated BMI (OR = 10.904) as independent predictors of severe hypoxemia.

Conclusion: Respiratory depression events are relatively common during deeply sedated gastroenteroscopies. The SBQ score effectively predicts this risk, particularly in identifying patients susceptible to severe hypoxemia. An SBQ score ≥ 3 serves as a practical threshold for recognizing high-risk individuals, with snoring, observed apnea, and high BMI as key warning indicators. SBQ is a valid and concise preoperative screening tool for this patient group.

Clinical trial registration: Registry: ClinicalTrials.gov; Name: Preoperative Assessment of Hypoxia Risk in Painless GI Endoscopy; URL: https://www.chictr.org.cn/showproj.html?proj=272808 .