Association between various clinical factors and delayed extubation (> 15 min). Statistical analysis was performed using a multiple logistic regression model. For quantitative data, odds ratios are described per value in parentheses. *P < 0.05, **P < 0.01. aAmerican Society of Anesthesiologists physical status. bComorbidities were extracted from the anesthesia ledger system (JSA-PIMS from Japanese Society of Anesthesiologists). cHypertension was defined as systolic blood pressure ≥ 140 mmHg, diastolic blood pressure as ≥ 90 mmHg, or the use of medications for blood pressure control. dDiabetes mellitus was defined as the use of oral hypoglycemic agents or insulin. eDeterioration of liver function was defined as AST >32, ALT >37, or the presence of cirrhosis. fDeterioration of renal function was defined as estimated GFR < 60 mL/min/1.73m2. gHeart failure was defined based on Framingham criteria .