Background: Our aim was to investigate the differences in postoperativehearing thresholds in patients undergoing coronary artery bypass grafting with (Group I, n=20) or without(Group II, n=17) extracorporeal circulation. Material/Methods: 37 patients undergoing coronary arterybypass grafting with or without extracorporeal circulation were prospectively evaluated in terms of hearingthreshold changes with the intention of documenting hearing losses postoperatively. The t-test for twoindependent variables was used for statistical analysis. Results: Hearing threshold changes were detectedin 9 Group I patients (45%) and 3 Group II patients (17.65%). The difference between the two groups wasstatistically significant (p=0.0426). Conclusions: Postoperative hearing threshold changes, not necessarilyrevealed by clinical examinations, are encountered after coronary artery bypass grafting operations.Extracorporeal circulation usage seems to bring an additional risk in terms of hearing loss.

Keywords: Auditory Threshold, Audiometry, Evoked Response, Coronary Artery Bypass, Extracorporeal Circulation, Hearing Loss - diagnosis, Postoperative Complications - diagnosis