| Since klineberg reported early extubation in patients undergoing elective coronary artery bypass graft (CABG) in 1970, it has been demonstrated that early extubation is feasible and safe with the improvement of cardiac surgery. Early extubation can improve ciliary function and mucous transport, reduce the risks of pneumonia, atelectasis and other pulmonary complications. Avoidance of the prolonged use of positive-pressure ventilation can augment left ventricular filling, which produce a higher cardiac output. Since 1990, the improved cardiac surgery, better intraoperative myocardial protection, improvements in cardiopulmonary bypass technology and cardiac anesthesia have allowed for early extubation in most patients following cardiac surgery with the reducing of complications.Fast-track cardiac surgery (FTCS) was advocated with the increasing of the population undergoing CABG and the escalating costs of care. FTCS is a process of care, including multidisciplinary approach aimed to facilitate tracheal extubation of patients within 4~8h after cardiac surgery, to reduce hospital length of stay, costs of care, and the incidences of morbidity and mortality.Meanwhile, many short-acting anesthetic agents, neuromuscular blocking agents or narcotics, new cardiovascular drugs have made fast-track cardiac anesthesia and early extubation possible in most patients after cardiac surgery.The criteria of extubation include: (1) Patient responsive and cooperative, (2) Negative inspiratory force >-20cm H2O, (3) Vital capacity >10ml/kg, (4) PaO2>80mmHg on FiO2≤0.5, (5) Cardiac index (CI)>2.2 L·min-1·m-2, (6) Temp>36.5℃, (7)Arterial blood gas PH>7.3, (8) Chest tube drainage<100ml/h for 2 hours, (9) Absence of uncontrolled dysrhythmia.It has been demonstrated that early extubation can be accomplished in more than 55%~80% of the entire group of nonselected patients regardless of preoperative condition, the complexity of the operation, or postoperative difficulty. Avoidance of positive-pressure ventilation can improve venous return, reduce right ventricular afterload, augment left ventricular filling, which improve hemodynamic performance. Faster awakening with use of short-acting narcotics, patients can cough and mobilize earlier, as well as recovered rapdlier.Early extubation reduces perioperative medication requirements, costs of care, resource utilization, ICU and hospital lengths of stay, but does not increase the morbidity. But questions still remain regarding early extubation: early extubation increases sympathetic tone leading to myocardia ischemia, tachycardia and hypertension, increase risk of bleeding if patient is hypertensive. Pain and splinting may causeatelectasis from hypoventilation, possibly higher risk of reintubation, higher metabolic demand may impair recovery, newer drugs are more expensive.It has been demonstrated the criteria for early extubation is: left ventricular ejection fraction >40% or off-pump CABG, relative exclusionary criteria include: (a) eventful operations, (b) perioperative hemodynamic instability, (c) large quantity of chest tube drainage or postoperative bleeding, (d) the time of cardiopulmonary bypass >120min, (e) hypoxemia or hypercarbia, (f) postoperative low cardiac output or ventricular arrythmia, (g) old age (>65), (h) complications of brain, lung, liver and renal.Meanwhile, a series of studies suggested the major determinants of delayed extubation are: (a) Old age, (b) Females and lower body surface area, (c) New York Heart Association functional class IV, chronic heart failure, or requirement of intraaortic balloon pump (IABP); (d) postoperative bleeding and bank blood transfusions, (e) Preoperative renal insufficiency, (f) Reoperations or emergent cases, (g) intraoperative fluid retention, (h) postoperative stroke, et al. But questions still remain regarding these determinants. Because of fewer patients having CABG in our country,and the lack of clinical experience,we do not have the same opionion on the timing of extubation after CABG...
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