title: Delayed bilateral vocal cord paresis after a continuous interscalene brachial plexus block and endotracheal intubation: A lesson why we should use low concentrated local anesthetics for continuous blocks.
abstract: BACKGROUND
  Recurrent laryngeal nerve block is an uncommon complication that can occur after an interscalene brachial plexus block (ISB), which may lead to vocal cord palsy or paresis. However, if the recurrent laryngeal nerve is blocked in patients with a preexisting contralateral vocal cord palsy following neck surgery, this may lead to devastating acute respiratory failure. Thus, ISB is contraindicated in patients with contralateral vocal cord lesion. To the best of our knowledge, there are no reports of bilateral vocal cord paresis, which occurred after a continuous ISB and endotracheal intubation in a patient with no history of vocal cord injury or surgery of the neck.
  
  
  METHODS
  A 59 year old woman was planned for open acromioplasty and rotator cuff repair under general anesthesia. General anesthesia was induced following an ISB using 0.2% ropivacaine and catheter insertion for postoperative pain control.
  
  
  METHODS
  While recovering in the postanesthesia care unit (PACU), however, the patient complained of a sore throat and hoarseness without respiratory insufficiency. On the morning of the first postoperative day, she still complained of mild dyspnea, dysphonia, and slight aspiration. She was subsequently diagnosed with bilateral vocal cord paresis following an endoscopic laryngoscopy examination.
  
  
  METHODS
  The continuous ISB catheter was immediately removed and the dyspnea and hoarseness symptoms improved, although mild aspiration during drinking water was still present.
  
  
  RESULTS
  On the 4th postoperative day, a laryngoscopy examination revealed that the right vocal cord movement had returned to normal but that the left vocal cord paresis still remained.
  
  
  CONCLUSIONS
  When ISB is planned, a detailed history-taking and examination of the airway are essential for patient safety and we recommend that any local anesthetics be carefully injected under ultrasound guidance. We also recommend the use of low concentration of local anesthetics to avoid possible paralysis of the vocal cord.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Hee-Sun
authors.initials: HS
authors.lastname: Park
authors.forename: Ha-Jung
authors.initials: HJ
authors.lastname: Kim
authors.forename: Young-Jin
authors.initials: YJ
authors.lastname: Ro
authors.forename: Hong-Seuk
authors.initials: HS
authors.lastname: Yang
authors.forename: Won-Uk
authors.initials: WU
authors.lastname: Koh
mesh_terms: D000779:Anesthetics, Local / Q000008:administration & dosage / Q000009:adverse effects; D065527:Brachial Plexus Block / Q000009:adverse effects* / Q000379:methods; D005260:Female; D006685:Hoarseness / Q000209:etiology; D006801:Humans; D007442:Intubation, Intratracheal / Q000009:adverse effects*; D008875:Middle Aged; D010612:Pharyngitis / Q000209:etiology; D011183:Postoperative Complications / Q000209:etiology*; D011184:Postoperative Period; D014826:Vocal Cord Paralysis / Q000209:etiology*
chemical_list: D000779:Anesthetics, Local