Incidence and Risk Factors of Postoperative Vocal Cord Paralysis in 987 Patients After Cardiovascular Surgery

Background Vocal cord paralysis (VCP) after cardiovascular surgery can affect the postoperative outcome. The aim of the present study was to clarify the incidence of VCP after cardiovascular surgery and the relationship between the surgery characteristics and the risk of VCP. Methods A total of 987 consecutive patients who underwent cardiovascular surgery (cardiac, n = 895; aortic, n = 92) were enrolled. We retrospectively assessed the incidence and the risk of VCP according to the length and types of surgery and the details of each VCP case and compared them between the aortic and the nonaortic group. Results Twenty-three patients (2.3%: cardiac, n =15; aortic, n = 8) were expertly diagnosed with VCP (left, n = 19; right, n = 2; bilateral, n = 2). In the multivariate analysis, the risk for VCP increased with the duration of the operation (odds ratio [OR], 4.4, 95% confidence interval [CI] 1.7 to 11.4), and aortic procedures (OR, 5.6, CI 2.3 to 13.5) exhibited higher risk compared with coronary artery bypass grafting. Among the VCP cases, the incidence of poor outcomes (ie, bilateral VCP, repeated airway treatment, death within 6 months) was significantly higher in the aortic group (p = 0.016). All patients that were intubated for longer than 100 hours exhibited poor outcomes. Conclusions Aortic procedures and prolonged operation increase the risk of VCP. Severe VCP tended to be associated with aortic surgery and intubation for more than 100 hours.