The Bezold-Jarisch Reflex Following an Endoscopic Endonasal Resection of an Intraosseous Clival Myxoma: A Case Report.

In certain contexts, young and healthy patients with a strong heart and a history of vasovagal syncope are at increased risk of cardiac arrest. An increase in vagal tone results in the normal maintenance of arterial pressure shifting into parasympathetic activation and sympathetic suppression, amplifying afferent mechanoreceptors and, in rare instances, inducing asystole. We report the case of a 17-year-old patient with a past medical history of syncope who went into asystole while maintaining consciousness and protecting his airway when recovering from anesthesia in the postanesthesia care unit (PACU) following endoscopic endonasal resection of an intraosseous clival myxoma. Chest compressions were initiated and epinephrine was administered, allowing for return of spontaneous circulation to be quickly achieved. While being transferred to the intensive care unit, the patient's heart rate dropped to 20 bpm while sitting in Fowler's position, causing vasovagal syncope which was then resolved by laying the patient supine and 0.8 mg of glycopyrrolate administration. The altered sympathetic to parasympathetic tone resulting in asystole within this case and cardiac beta-agonist stimulation by epinephrine injection provide evidence that the Bezold-Jarisch reflex occurred. This case suggests that the intracranial internal carotid arteries can potentially display similar mechanical sensitivity as the carotid sinus and questions the validity of electrocardiogram readings during this reflex, as the patient remained conscious while in asystole.