Acute Bradycardia as a Result of Intraoperative Transcranial Electric Motor Evoked Potential Stimulation: A Case Report

• Published in: American journal of electroneurodiagnostic technology 2003-06, Vol.43 (2), p.98-104
• Main Authors: Ponder, Brian L., Conner, Troy F., Floyd, David T., Tao, Cheng, Enyia, Okechuku K.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Bradycardia; cardiac arrhythmia; Cerebrospinal fluid. Spinal cord. Spinal roots. Spinal nerves; intraoperative; Medical sciences; monitoring; motor evoked potentials; Neurosurgery; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases
• ISSN: 1086-508X; 2375-8619
• DOI: 10.1080/1086508X.2003.11079424

This is a case report of an episode of acute bradycardia following intraoperative transcranial electric motor evoked potential (tc e MEP) stimulation. Review of the literature showed no reported cases of induced bradycardia as a result of tc e MEP stimulation during surgery. Our patient underwent anterior cervical discectomy and fusion of the C3 and C4 intervertebral space to treat cervical stenosis. During the procedure, a significant drop in heart rate was detected immediately following tc e MEP stimulation. The heart rate of the patient slowly returned to baseline normal sinus rhythm and showed no further arrhythmia within minutes of stimulation. The consequences of profound or sudden bradycardia may cause symptoms such as loss of energy, weakness, and fainting attacks in the conscious patient. Intraoperatively, under general anesthesia, profound bradycardia can result in hypotension and decreased cardiac output. An awareness of the possibility of this finding during intraoperative tc e MEP monitoring should facilitate a timely anesthesia team intervention, when necessary.