Independent predictors of prolonged mechanical ventilation after coronary artery bypass surgery

To determine independent predictors of prolonged mechanical ventilation in patients undergoing coronary artery bypass graft surgery.

Data of patients undergoing coronary artery bypass graft surgery were included prospectively from July 2009 to July 2010. All data were input into an electronic database. The resulting cohort included a total of 2952 patients of which 77 remained more than 48 hours on mechanical ventilation. Patients were divided into two groups: 1) a prolonged ventilation group, needing mechanical ventilation for more than 48 hours and 2) not prolonged ventilation group, undergoing a successful extubation within 48 hours.

After adjustment for confounding factors a multivariate analysis identified the following factors as independent predictors of prolonged mechanical ventilation: age (OR 1.06 95% CI 1.03 -1.09; P <0.001), chronic renal failure (OR 3.52 95% CI 1.84 - 6.74; P <0.001), chronic obstructive pulmonary disease (OR 2.65 95% CI 1.38 -5.09; P = 0.004), coronary artery bypass graft associated with other procedures (OR 3.33 95 % CI 1.89 - 5.58; P <0.001) and clamping time (OR 1.01 95% CI 1.00 -1.02; P = 0.018).

The identification of these predictors allows the development of preventive strategies that could reduce invasive ventilation time, since patients on prolonged mechanical ventilation present greater morbidity and mortality rates.