Cardiovascular disease is the leading cause of mortality in most developed and developing countries. Cardiac surgery has become a standard treatment for some patients with heart diseases and CABG is a common and successful procedure for coronary revascularization.The incidence of post-operative respiratory complications after thoracotomy ranges from 10% to 40%. As well as significantly contributing to morbidity and peri-operative mortality, they increase length of hospital stay and hospital costs. The incidence rate also depends on the surgical site, presence of risk factors and the criteria used to define post pulmonary complications.