Unilateral Vocal Fold Immobility after Prolonged Endotracheal Intubation

Importance: Endotracheal intubation and mechanical ventilation are life-saving treatments for acute respiratory failure but are complicated by significant rates of dyspnea and dysphonia after extubation. Unilateral vocal fold immobility (UVFI) after extubation can alter respiration and phonation, but its incidence, risk factors, and pathophysiology remain unclear. Objectives: To determine the incidence of UVFI after prolonged (>12 hours) mechanical ventilation in a medical intensive care unit and investigate associated clinical risk factors for UVFI after prolonged mechanical ventilation. Design, Setting, and Participants: This subgroup analysis of a prospective cohort study was conducted in a single-center medical intensive care unit from August 17, 2017, through May 31, 2018, among 100 consecutive adult patients who were intubated for more than 12 hours. Patients were identified within 36 hours of extubation and recruited for study enrollment. Those with an established tracheostomy prior to mechanical ventilation, known laryngeal or tracheal pathologic characteristics, or a history of head and neck radiotherapy were excluded. Exposure: Invasive mechanical ventilation via an endotracheal tube. Main Outcomes and Measures: The incidence of UVFI as determined by flexible nasolaryngoscopy. Results: One hundred patients (62 men [62%]; median age, 58.5 years [range, 19.0-87.0 years]) underwent endoscopic evaluation after extubation. Seven patients had UVFI, of which 6 cases (86%) were left sided. Patients with hypotension while intubated (odds ratio [OR], 10.8; 95% CI, 1.6 to ∞), patients requiring vasopressors while intubated (OR, 16.7; 95% CI, 2.4 to ∞), and patients with a preadmission diagnosis of peripheral vascular disease (OR, 6.2; 95% CI, 1.2-31.9) or coronary artery disease (OR, 5.1; 95% CI, 1.0-25.5) were more likely to develop UVFI. Conclusions and Relevance: Unilateral vocal fold immobility occurred in 7 of 100 patients in the medical intensive care unit who were intubated for more than 12 hours. Unilateral vocal fold immobility was associated with inpatient hypotension and preadmission vascular disease, suggesting that ischemia of the recurrent laryngeal nerve may play a role in disease pathogenesis.