Incidence of adverse events during emergency department procedural sedation by ASA Physical Status Classification: a multicenter prospective study

Abstract Objective The American Society of Anesthesiologists (ASA) Physical Status Classification System is widely used to estimate procedural risk. However, its utility in adult emergency department (ED) patients undergoing procedural sedation and analgesia (PSA), particularly the elderly, remains unclear. This study evaluated the association between ASA classification and adverse events (AEs) during PSA, with a focus on patients aged ≥ 65 years. Methods This secondary analysis of a multicenter prospective registry (JPSTAR) included adult patients (≥ 18 years) who underwent PSA in the ED between 2017 and 2023. Patients were categorized into ASA I–II and ASA ≥ III groups. The primary outcome was the occurrence of any AE. Multivariable logistic regression was used to calculate adjusted odds ratios (aORs), controlling for clinical confounders. Subgroup analyses were performed by sedative type. Results Among 1,084 patients, 297 (27.4%) were classified as ASA ≥ III. The ASA ≥ III group was older than the ASA I–II group (median age: 76 vs. 68 years). The incidence of all AEs was higher in the ASA ≥ III group (26.9% vs. 17.9%; aOR: 1.48; 95% CI: 1.05–2.09). Hypoxia (SpO₂ < 90%) was the most common AE, especially in the ASA ≥ III group (14.5% vs. 9.4%). Among patients aged ≥ 65 years, ASA ≥ III remained significantly associated with AEs (aOR: 1.80; 95% CI: 1.22–2.68). Propofol use was associated with more AEs in ASA ≥ III patients (46.4% vs. 15.6%). Conclusion ASA ≥ III status is associated with increased AEs during PSA, particularly in elderly patients,