Abducens paralysis—a rare complication of spinal anesthesia at an emergency department: a case report

Abstract

The abducens nerve is known as the sixth cranial nerve (CN VI) and is characterized by the longest intracranial course of all cranial nerves [1]. The abducens nerve is a pure motor neuron that provides lateral retraction of the eyeball with innervation of the musculus rectus externus. CN VI palsy has been included in the literature as a rare complication, among all spinal blockades, of spinal anesthesia [2]. CN VI palsy after spinal anesthesia was first described in two cases published by Hayman and Wood [3]. CN VI palsy, which developed after spinal anesthesia for endoscopic urological surgery, was valuable for presentation in this case, which was noticed in the emergency department. CASE REPORTA 38-year-old male patient was admitted to the emergency department due to increasing dizziness, diplopia, and limited lateral gaze for 2 days. The patient presented with the complaint of orthostatic headache. The patient reported endoscopic urological surgery under spinal anesthesia 1 week prior. Physical examination and vital signs of the patient with no known comorbid conditions were normal. The cranial nerve examination revealed binocular diplopia and lateral gaze limitation in the left eye, based on which unilateral CN VI palsy was considered. Immediate eye and neurology consultations were requested. The fundoscopic exam-The sixth cranial nerve (CN VI) is a rare site of complication associated with spinal anesthesia and can produce secondary symptoms of ocular muscle palsy. A 38-year-old man was admitted to the emergency department with complaint of diplopia and limited lateral gaze in the first week after endoscopic urological surgery under spinal anesthesia. Isolated unilateral CN VI palsy was considered after excluding differential diagnoses. Ocular palsy and diplopia regressed with conservative treatment during follow-up, and the patient was discharged. This article aims to show that CN VI palsy is a rare complication of spinal anesthesia, which can be observed in the emergency department.