Predictors of prolonged mechanical ventilation in a cohort of 3,269 CABG patients.
BACKGROUND
Prolonged mechanical ventilation after heart surgery is associated with increased patient morbidity and mortality (4.9% vs 22-38%). A prospective observational cohort study was carried out to assess the predictors of prolonged mechanical ventilation and its impact on hospital survival in a cardiac surgical patient cohort admitted to our 8 bed postoperative ICU from January 1997 through June 2004.


METHODS
All of the patient perioperative and ICU variables were input into an electronic database. Patients were divided into: 1) an Early Extubation group, undergoing a successful extubation within 12 h and 2) a Delayed Extubation group, needing mechanical ventilation longer than 12 h.


RESULTS
A total of 3,269 patients undergoing a coronary artery bypass graft operation were admitted. A multivariate Logistic Regression model allowed us to identify: 1) redo surgery (OR = 3.090, 95% CI = 1.655-5.780); 2) cardiopulmonary bypass time longer than 91' (OR = 1.390, 95% CI = 1.013-1.908); 3) intraoperative transfusions of more than 4 units of red blood cells (OR = 3.144, 95% CI = 2.331-4.255) or fresh frozen plasma (OR = 2.976, 95% CI = 1.984-4.830); and 4) left ventricular ejection fraction = or < 30% (OR = 2.444, 95% CI 1.291-3.205) as independent predictors of prolonged mechanical ventilation. The Early Extubation group showed a significantly higher cumulative survival 180 days after the ICU admission (Log-Rank = 16.617, p=0.000).


CONCLUSIONS
This audit allowed us to assess a predictive model identifying a priori coronary artery bypass graft patients that are more likely to undergo prolonged mechanical ventilation.
Department of Cardiac Anaesthesia, Luigi Sacco Hospital, Milan, Italy.
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Cislaghi
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Condemi
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Corona
D000368:Aged; D000704:Analysis of Variance; D015331:Cohort Studies; D001026:Coronary Artery Bypass / Q000401:mortality; D005260:Female; D005544:Forecasting; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology* / Q000401:mortality / Q000628:therapy*; D011379:Prognosis; D012121:Respiration, Artificial; D012189:Retrospective Studies; D016019:Survival Analysis