PREDICTORS OF EARLY EXTUBATION AFTER CARD IAC-SURGERY

Background: Following open heart surgery, most patients are ventilated for 12 to 24 hours to obtain a period of hemodynamic stability and to reduce the work of breathing. Some authors have proposed criteria to guide early extubation and have proposed physiologic parameters to pre dict which patients will be able to breathe spontaneously. Aim: To stu dy the capacity to predict successful early extubation of ventilatory and gas exchange parameters. Patients and method: Two hundred thirty p atients admitted to any intensive care unit after coronary or vascular surgery were studied. Measurements were made through a T piece 30 min utes after discontinuing mechanical ventilation. Results: Six patients died in the postoperative period. Two hundred ten patients tolerated early extubation (14 +/- 5 h of mechanical ventilation) and 20 require d prolonged mechanical ventilation (74 +/- 107 h). The latter had long er surgical procedures (291 +/- 65 and 240 +/- 67 min respectively) an d extracorporeal circulation times (138 +/- 42 and 104 +/- 43 min resp ectively), required more vasoactive drugs, had more episodes of confus ion and had a higher surgical risk. Tidal volume, respiratory frequenc y, maximal inspiratory pressure and blood gases at the moment of extub ation were similar in both groups. Conclusions: Pulmonary function par ameters and blood gases measured during a T piece trial are not good p redictors of early extubation in cardiac surgery.