Risk factors for the development of pneumonia post cardiac surgery

Postoperative pneumonia is a devastating complication after cardiac surgery that increases morbidity and mortality. The objective of this study was to identify potential risk factors for the development of nosocomial pneumonia post cardiac surgery by the way of logistic regression analysis.

Data of the last 162 patients undergoing cardiac surgery before November 2009 were retrospectively collected and analysed.

The mean age of the patients was 65.57 ± 10.48 years and 83 (51%) were male. Postoperative pneumonia was diagnosed in 21 (13%) patients. The mean remaining time in the intensive care unit and mean length of hospitalisation were longer for patients with postoperative pneumonia. Pre-operative heart rate, previous diabetes mellitus, previous chronic obstructive pulmonary disease, postoperative urea, creatinine and potassium levels, extubation time, postoperative atrial fibrillation, and number of units of transfused packed red blood cells (pRBC) and fresh frozen plasma were associated with higher occurrence of postoperative pneumonia on univariate analysis.

On logistic regression analysis, pRBC transfusion, previous chronic obstructive pulmonary disease and postoperative atrial fibrillation remained as independent predictors for the development of postoperative pneumonia.