Following total thyroidectomy the patient develops respiratory stridor. The cause is:

(a) B/L recurrent laryngeal nerve paralysis(Ref. Current Diagnosis & Treatment Otolaryngology, Lalwani, 3rd ed., 478)In B/L recurrent laryngeal nerve paralysis the vocal cords will be in median position, leading to stridor.Note: This is the only vocal cord palsy with stridor, breathing is normal in the remaining palsies.