Comparison of the Effect of Incentive Spirometry on Pulmonary Volumes and Arterial Blood Gases after Coronary Artery Bypass Surgery

ABSTRACT : Introduction & Objective: Following thoracic and abdominal surgery, all patients experience a decrease in pulmonary volumes and atelectasis. Different methods such as lung physiotherapy, intermittent positive pressure breathing, positive expiratory pressure and incentive spirometry are suggested for improvement of pulmonary volumes and blood gas parameters in these patients. Due to cheap, simple and easy use of incentive spirometry, we aimed at evaluating the effects of it on pulmonary volumes and blood gases parameters (ABG) in coronary artery bypass patients. Materials & Methods: This is a randomized, clinical trial study. From February 2004 to February 2005, 150 consecutive male patients who were hospitalized for coronary artery bypass surgery in Madani heart hospital were divided into two groups at random. On the first day of operation, group I used incentive spirometry and group II was routinely followed up. Data were collected through a questionnaire including age, left ventricular function (LVEF), smoking and number of grafts. Blood gases parameters and spirometry volumes were measured in 3 phases before, in the morning of the first day of operation and after using incentive spirometry. Data were analyzed by SPSS software using paired or unpaired student’s t-test. Results: There were no significant differences between two groups as to the mean age, LVEF, number of grafts and duration of mechanical ventilation in ICU. Comparison of ABGs before anesthesia and on the first day of surgery showed a significant decrease in systemic O2 saturation and arterial Po2 in all cases (p