Bilateral abductor vocal cord palsy and pregnancy: a case report

Abstract

Introduction/backgroundBilateral abductor vocal cord palsy in pregnancy is a rareclinical problem. Due to the rarity of this condition, there isno definite guideline on obstetric management.CaseA 23-year-old primigravida was referred to our tertiaryhospital at 23 weeks gestation. Her prior antenatal care hadbeen with a primary health care clinic. She was diagnosedwith papillary carcinoma of the thyroid when she was17 years old, and had undergone a total thyroidectomy. Shehad since been in remission, and had been on thyroxine200 lg daily. She reported hoarseness of voice since herthyroidectomy, but did not have respiratory compromise.On presentation, she complained of stridor, snoring andworsening episodes of sleep apnoea since early in thesecond trimester. On examination, her pulse rate was88 bpm, her blood pressure was 120/80. Her respiratoryrate was 20/min. Stridor was audible even without aus-cultation. Auscultation of her lungs was unremarkable. Heruterus size corresponded to her dates and ultrasonographyrevealed a structurally normal foetus with normal growthparameters. She was then referred to an otorhinolaryngol-ogist for assessment. A flexible laryngoscopy showedbilateral abductor vocal cord palsy in paramedian position(Fig. 1).Her condition remained stable until 32 weeks when herstridor worsened and she was having more difficultybreathing. A decision was made to electively insert a tra-cheostomy at 36 weeks, and to perform a lower segmentcaesarean section at 38 weeks. However, ultrasonographyat 36 weeks showed evidence of intrauterine growthrestriction (IUGR) and an amniotic fluid index of 6.0.Under general anaesthesia, a size 7.5 tracheostomy tubewas inserted. At the same sitting, lower segment caesareansection was performed uneventfully. A baby girl weighing2,600 g was delivered with an Apgar score of 8 at 1 minand 9 at 5 min. Estimated blood loss was 400 ml. Twoweeks later, left laser cordectomy was performed followedby removal of the tracheostomy. On follow-up 2 weekslater, her voice was still hoarse but she no longer hadstridor.DiscussionAbductor vocal cord palsy is caused by damage to one orboth recurrent laryngeal nerves (RLN). RLN palsy is acommon complication following neck/thyroid surgery witha reported frequency of 6.6–13.2 % [1, 2]. The incidencefollowing thyroidectomy for thyroid carcinoma is 10.1 %[3]. In bilateral RLN palsy, the vocal cords remain in theparamedian position. It commonly presents as stridor andhoarseness of voice. It may occur due to direct or indirectsurgical denervation of the RLN, or it can happen due to