OBJECTIVE To identify preoperative, intraoperative, and postoperative predictors of early (6 hours or less after surgery) and delayed (more than 6 hours) extubation after coronary artery bypass graft surgery. METHODS The sample for this prospective nonrandomized study consisted of 116 consecutive patients in a 12-bed cardiothoracic ICU who had coronary artery bypass graft surgery in a 6-month period and were followed up prospectively until transfer to an observation unit. RESULTS Age and the presence of early hemodynamic instability (within the first 3 hours after ICU admission) were independent predictors of intubation times of more than 6 hours when each was considered in separate multivariate models of preoperative, intraoperative, and postoperative variables. In a combined model, when considered with age and ejection fraction, the presence of early hemodynamic instability increased the odds by 4.7 times that extubation would occur more than 6 hours after surgery. For every 1 year increase in age, the odds of extubation occurring more than 6 hours after surgery increased by 6.5%. CONCLUSIONS Older age and the presence of early hemodynamic instability are associated with postoperative intubation periods of more than 6 hours after coronary artery bypass graft surgery. Clinicians should evaluate extubation goals in older patients carefully. Clinical management of hemodynamic instability should be aimed at prompt optimization of myocardial oxygen supply to limit ischemia and its sequelae.