BACKGROUND Despite numerous advances in anesthesia, surgical techniques, and postoperative care for coronary artery bypass graft (CABG) surgery, postoperative pulmonary complications (PPCs) still account for postoperative morbidity. OBJECTIVE To determine current risk factors for PPCs in CABG surgery patients. METHODS A retrospective cohort design was used. Health records were reviewed for patients (n=315) who had CABG surgery at a large quaternary healthcare center over a 4 month period. Pre-, peri-, and postoperative risk factors for PPCs were recorded as binary variables. Data were further assessed according to PPCs and non-PPCs using logistic regression models. RESULTS PPCs occurred in 99.4% of this CABG surgical cohort. Atelectasis, pleural effusion, atelectasis with pleural effusion, and pneumonia were the most frequent PPCs post CABG surgery. Age >65 years, diabetes, and ASA classification >3 were found to be related to the presence of atelectasis. No significant risk factors were related to the development of pleural effusion or atelectasis with pleural effusion. Postoperative pneumonia was associated with previous myocardial infarction, ventilation >10 h, and hospital stay >5 days. History of bronchitis and COPD were related to postoperative pneumothorax; history of heart failure, COPD, and other lung diseases were related to postoperative pulmonary edema. CONCLUSION These findings contribute to the understanding of PPCs in post-CABG surgery patients and assist in identification of patients at risk for developing PPCs.