Multiple cervical levels: increased risk of dysphagia and dysphonia during anterior cervical discectomy.

Background: Anterior cervical discectomy (ACD) is widely used for symptomatic cervical spine pathologies. The most common complications associated with this type of surgery are dysphagia and dysphonia; however, the risk factors associated with them have not been adequately elucidated. The purpose of this study is to assess the incidence of self-reported dysphagia and dysphonia and the associated risk factors after ACD.

Methods: This study used a retrospective chart review of 149 patients who underwent ACD at a tertiary care facility operating in the New York metropolitan area over a period of 2½ years. Charts for ACD patients were reviewed by 6 trained researchers. Incidence rates for self-reported dysphagia and dysphonia were calculated using 95% exact confidence intervals (CI). Risk factors such as age, sex, surgical hours, number of disc levels, airway class, American Society of Anesthesiologists class, fiberoptic intubation, and intubation difficulty were assessed using logistic regression.

Results: The incidence of self-reported dysphagia was 12.1% (95% exact CI, 7.3%-18.4%); for dysphonia the self-reported incidence was 5.4% (95% exact CI, 2.3%-10.3%). Patients who underwent surgery at ≥4 cervical levels had a significant 4-fold increased risk (odds ratio=4; 95% CI, 1.1-13.8) of developing dysphonia and/or dysphagia compared with patients who underwent surgery at a single surgical level.

Conclusions: This study confirms previous findings that the risk of developing dysphagia and/or dysphonia increases with the number of surgical levels, with multiple cervical levels representing a significantly higher postoperative risk, as compared with surgery at 1 level.