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Vocal Fold Paralysis Following Spinal Anesthesia

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Vocal Fold Paralysis Following Spinal Anesthesia Research Case Report/Case Series Vocal Fold Paralysis Following Spinal Anesthesia Elizabeth Guardiani, MD; Lucian Sulica, MD IMPORTANCE Transient upper cranial neuropathy is a well-described complication of spinal anesthesia. Lower cranial neuropathies, in particular vagal neuropathies, have not been described. We present 4 cases of vocal fold paralysis (VFP) in 3 patients following spinal anesthesia and discuss a proposed mechanism. OBSERVATIONS Three women presented with dysphonia following spinal anesthesia and were found to have unilateral VFP. Patient 1 presented with dysphonia immediately after knee surgery. Patient 2 developed right VFP 1 week after vaginal delivery with spinal epidural anesthesia. Two years later, she presented with sudden onset of dysphonia 3 days after another vaginal delivery with spinal and epidural anesthesia; a contralateral VFP was found. Patient 3 noted dysphonia 4 days after knee surgery and was found to have left VFP. No Author Affiliations: Department of patient had undergone intubation, and none had a central line on the side of the weakness. Otorhinolaryngology–Head and Neck Surgery, University of Maryland Imaging ruled out a relevant lesion. All 3 women had evidence of substantial recovery of School of Medicine, Baltimore motion at 6-month follow-up. (Guardiani); Parker Institute for Voice Disorders, Weill Cornell Medical CONCLUSIONS AND RELEVANCE Intracranial hypotension resulting in vagal neuropathy is a College, New York, New York (Sulica). possible complication of spinal anesthesia and appears to be the cause of transient vocal fold Corresponding Author: Elizabeth palsy in these 4 cases. Guardiani, MD, Department of Otorhinolaryngology–Head and Neck Surgery, University of Maryland JAMA Otolaryngol Head Neck Surg. 2014;140(7):662-663. doi:10.1001/jamaoto.2014.721 School of Medicine, 16 S Eutaw St, Published online May 15, 2014. Ste 500, Baltimore, MD 21201 ([email protected]). pinal anesthesia is a commonly used alternative to gen- mobile right vocal fold. This finding was confirmed on repeat stro- eral anesthesia for surgical procedures of the lower ex- boscopy in the office. She subsequently underwent computed S tremities, perineum, or lower abdomen. Cranial nerve tomography (CT) of the neck, which did not reveal any lesions palsy is a rare complication of spinal anesthesia. The incidence along the recurrent laryngeal nerve. A laryngeal electromyogra- is not well defined; however, older literature reports an incidence phy was performed at 3 months following surgery. This showed of 1 in 200 to 1 in 1200 cases.1 The most commonly affected is the evidence of denervation of the right thyroarytenoid (innervated abducens nerve, which usually presents between the second and by the recurrent laryngeal nerve) and cricothyroid muscle (in- fifth postoperative day with diplopia.2 Palsies of the oculomo- nervated by the superior laryngeal nerve), consistent with a right tor, facial, trigeminal, and trochlear nerves, as well as transient vagal (as opposed to recurrent laryngeal) neuropathy.The patient hypoacusis and Horner syndrome, have also been reported.3-7 subsequently underwent injection medialization with methyl- These palsies are typically transient and resolve within weeks to cellulose with satisfactory improvement in voice. Three months months. Cranial neuropathies have also been reported follow- later (6 months after injury), stroboscopy was repeated, reveal- ing lumbar puncture, myelography, spontaneous intracranial ing some return of motion of the right vocal fold with a small hypotension,8 and inadvertent dural tear during lumbar spine pseudocyst; voice continued to be adequate. At 1-year follow-up, surgery.9 Lower cranial neuropathies following instrumentation the right vocal fold was mobile but with some signs of residual of the dural space have not been described to our knowledge. paresis, including increased size of the pseudocyst. Herein we present 4 cases of vocal fold paralysis (VFP) that seem to have been caused by spinal anesthesia. Patient 2 A woman in her 60s underwent a total arthroplasty of the right knee under spinal anesthesia and conscious sedation. A right Report of Cases central venous catheter was placed in the internal jugular vein, and no instrumentation was introduced by mouth. On post- Patient 1 operative day 4, she noted onset of hoarseness and choking A woman in her 50s underwent a total arthroplasty of the right with liquids; she believed that her voice had been normal im- knee under spinal anesthesia and conscious sedation with no in- mediately after surgery. She was discharged to home but was strumentation introduced by mouth or cervical line placement. readmitted 2 weeks after surgery with a wound infection. Bed- In the recovery room, she was noted to have breathy dysphonia, side laryngoscopy performed at that time revealed a left VFP. and flexible laryngoscopy performed at that time revealed an im- Her hoarseness persisted, and stroboscopy performed 3 months 662 JAMA Otolaryngology–Head & Neck Surgery July 2014 Volume 140, Number 7 jamaotolaryngology.com Copyright 2014 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/28/2021 Vocal Fold Paralysis Following Spinal Anesthesia Case Report/Case Series Research later as an outpatient procedure revealed dense paresis of the sis of vocal fold immobility. However, a causal relationship may left side. Results of CT of the neck and the chest were within be considered in light of the documented occurrence of up- normal limits. The patient elected to undergo watchful wait- per cranial neuropathy as a complication of spinal anesthe- ing. At 6 months follow-up she had evidence of substantial re- sia, especially in the absence of important confounding fac- covery, and at 1 year her voice had improved to near normal tors. The onset of symptoms, ranging from immediate to 7 days and only mild residual paresis was noted on stroboscopy. after surgery in our patients, is consistent with previously re- ported cases of cranial neuropathy following spinal anesthe- Patient 3 sia. So too is the transient nature of these vocal fold palsies. A pregnant woman in her 30s underwent normal vaginal deliv- Cranial neuropathy following dural puncture is thought to ery with combined spinal epidural anesthesia. Approximately be due to reduction of cerebral spinal fluid volume and conse- 1 week postpartum, she noted hoarseness, effortful voice pro- quent decreased intracranial pressure. This is hypothesized to duction, and a single episode of choking and laryngospasm. She cause traction on the nerve at the level of the brainstem or pos- was evaluated in the emergency department of an outside in- sibly compression of the nerve by surrounding structures (eg, stitution, where CT of the chest was performed to rule out a pul- brain parenchyma, blood vessels).1,10 This idea is supported by monary embolus and flexible laryngoscopy revealed a right VFP. the fact that transient cranial neuropathies have also been re- Stroboscopy performed 1 week later confirmed the finding of ported in spontaneous intracranial hypotension.8 In our pa- an immobile right vocal fold. The patient was prescribed ste- tient who underwent laryngeal electromyography, this was sug- roids according to a tapering protocol, and a neck CT scan was gestive of a vagal lesion, given the evidence of denervation of performed with results within normal limits. The patient did not the cricothyroid muscle (innervated by the superior laryngeal return for follow-up because her voice slowly returned to nor- nerve in addition the thyroarytenoid), rather than an isolated mal over several months. She returned 2 years later with new neuropathy of the recurrent laryngeal nerve; this lends sup- hoarseness that began 3 days after a second normal vaginal de- port to the hypothesis of traction on the vagus nerve rather than livery with combined spinal epidural anesthesia. Stroboscopy an idiopathic palsy, the majority of which are recurrent nerve performed 5 days postpartum revealed a fully mobile right vo- phenomena. Holes in the dura can continue to leak following cal fold and an immobile left vocal fold. Results of CT of the neck puncture, and continued egress of spinal fluid may result in a and chest and magnetic resonance imaging of the brain were delayed presentation of the neuropathy, as was the case in 3 of within normal limits. A neurologic evaluation and autoim- our 4 cases. Because of this, combined with the lack of recog- mune workup failed to reveal any cause for neuropathy. The pa- nition of spinal anesthesia as a potential cause, these neuropa- tient was treated with steroids according to a tapering protocol thies may be overlooked or attributed to other factors. and watchful waiting. At 6-month follow-up, she reported that her voice quality was back to normal; stroboscopy revealed only mild residual paresis of the left vocal fold. Conclusions Vocal fold paralysis seems to be a potential complication of spi- Discussion nal anesthesia and should be considered in patients present- ing with dysphonia shortly after such a procedure. In the ab- At first glance, these cases of VFP may be classified as idio- sence of other findings on workup, these patients may expect pathic despite the coincidence of onset because spinal anes- complete or near-complete functional recovery weeks to thesia is generally not considered in the differential diagno- months after onset. ARTICLE INFORMATION Previous Presentation: This work was presented anesthesia. Trans Pa Acad Ophthalmol Otolaryngol. Submitted for Publication: November 22, 2013; as a poster presentation at the 2013 Fall Voice 1990;42:972-973. final revision received January 13, 2014; accepted Conference; October 18-19, 2013; Atlanta, Georgia. 6. King RA, Calhoun JH. Fourth cranial nerve palsy January 21, 2014. following spinal anesthesia: a case report. J Clin REFERENCES Published Online: May 15, 2014. Neuroophthalmol. 1987;7(1):20-22. doi:10.1001/jamaoto.2014.721. 1. Robles R. Cranial nerve paralysis after spinal 7. Fang JY, Lin JW, Li Q, Jiang N, Gao Y. Trigeminal anesthesia.
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