Comparing the Effects of Volume-Time Curve and Stethoscope Methods in Tube Cuff Inflation on Frequency of Atelectasis Following Coronary Artery Bypass Graft surgery

Abstract

Background and purpose: Inappropriate pressure of the endotracheal cuff causes aspiration of oral secretions in airway resulting in atelectasis. This study aimed at comparing the effects of two methods of filling the endotracheal cuff on the frequency of atelectasis in patients following coronary artery bypass graft surgery. Materials and methods: In this clinical trial, 206 candidates for coronary artery bypass graft surgery in Mazandaran Heart Center were selected and randomly divided into two groups. In the first group, air leakage was controlled by volume-time curve and in the second group it was controlled by stethoscope. Chest x-ray was obtained to look for atelectasis. A researcher-made checklist was used to record the information. Data analysis was done in SPSS V21. Results: Frequency of atelectasis was 67% in first group and 80.6% in the second group (P=0.027) which showed that in volume-time method less air leakage occurred, therefore, aspiration and frequency of atelectasis decreased too. Conclusion: According to current study, volume-time curve method decreased the frequency of atelectasis resulting in better oxygenation and gas exchanges. Therefore, this low-cost and low-risk method is suggested for post-heart surgery care to lower pulmonary side effects. (Clinical Trials Registry Number: IRCT2017091319677N4)

Keywords

• endotracheal cuff pressure
• coronary artery bypass
• pulmonary atelectasis
• air leakage
• volume –time curve