title: Risk factors for recurrent laryngeal nerve neuropraxia postthyroidectomy.
abstract: OBJECTIVE
  Despite preservation of the recurrent laryngeal nerve (RLN), transient vocal cord paralysis (VCP) occurs after 1.2% to 10.9% of thyroidectomies. The objective of this study was to study risk factors for transient VCP after thyroidectomy.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  Academic teaching hospital.
  
  
  METHODS
  Two hundred fifteen consecutive thyroid surgeries performed by a single surgeon. All patients underwent preoperative and postoperative laryngoscopy. Patients with preexisting VCP or without postoperative laryngoscopy were excluded. Clinical and operative data were recorded prospectively at the time of thyroid surgery. The association between possible risk factors and occurrence of postoperative transient VCP was studied.
  
  
  RESULTS
  Six patients were excluded (2 with preexisting VCP and 4 without postoperative laryngoscopy). There was 1 intentional sacrifice of an RLN and 1 unintentional RLN transection. Of the remaining 322 RLNs at risk, 15 (4.7%) had postoperative VCP. Operative findings of cancer invading the RLN requiring sharp dissection to separate the nerve (P = .006) and operative findings of RLN extensively draped along the thyroid or intimately associated with the thyroid parenchyma at Berry's ligament (P = .03) were significantly associated with VCP. Revision surgery (P = .06) trended toward significance. Malignancy, central compartment neck dissection, extralaryngeal RLN branching, hyperthyroidism, and retrosternal extension were not significant. Of cases with follow-up laryngoscopic documentation of vocal function, 85% (11/13) showed full resolution of VCP, with 1 further case showing partial recovery.
  
  
  CONCLUSIONS
  Invasive cancer and variants in the anatomic course of the RLN are risk factors for transient VCP after thyroidectomy.
authors.affiliation: Department of Otolaryngology-Head & Neck Surgery, South Infirmary Victoria University Hospital, Cork, Ireland. sheahan.patrick@sivuh.ie
authors.forename: Patrick
authors.initials: P
authors.lastname: Sheahan
authors.forename: Ann
authors.initials: A
authors.lastname: O'Connor
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Murphy
mesh_terms: D015331:Cohort Studies; D006801:Humans; D007828:Laryngoscopy; D020127:Recovery of Function; D012009:Recurrent Laryngeal Nerve / Q000473:pathology* / Q000503:physiopathology; D012307:Risk Factors; D013959:Thyroid Diseases / Q000150:complications / Q000473:pathology* / Q000601:surgery*; D013965:Thyroidectomy / Q000009:adverse effects*; D016896:Treatment Outcome; D014826:Vocal Cord Paralysis / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology