The aim of the study was to determine factors which may have influence on the occurrence of respiratory failure in patients operated on because of coronary heart disease (ischemic heart disease). A group of 137 patients who underwent coronary artery bypass grafting in the years 2005-2009 were examined. For this purpose the influence of preoperative, intraoperative and postoperative factors on the occurrence of respiratory failure was examined. Preoperative brain stroke, arrhythmia, patients’ age were identified as risk factors. Decrease in ejection fraction of left ventricle, raised level of urea, adrenaline administration, low cardiac output syndrome, cardiogenic shock, necessity to use IABP, nebulization treatment and antibiotic therapy were among postoperative factors which may cause the occurrence of respiratory failure. In sum, apart from the above-mentioned pre- and postoperative factors, the occurrence of cardiogenic pulmonary edema influences the occurrence of respiratory failure and its prolonged treatment. The necessity of intratracheal intubation may be caused by postoperative complication with extrapulmonary sepsis.