Intraoperative Bradycardia and Asystole

Abstract

The case of a 71-year-old man undergoing a transhiatal esophagectomy due to Barrett’s esophagus is presented. The surgery began as a laparoscopic procedure which was converted to an open procedure due to the patient’s body habitus. Initial surgical attempts to free the esophagus resulted in transient bradycardic episodes, with spontaneous restoration of vital signs after cessation of the offending stimulus. However, on the last attempt, the patient developed profound bradycardia and ensuing asystole requiring pharmacologic resuscitation and chest compressions. Vagal and other physiologic reflexes that can lead to bradycardia and their management strategies are presented. In particular, vagus nerve traction, oculocardiac, Bezold-Jarisch, and baroreceptor reflex are discussed. Possible mechanisms leading to rhythm disturbances during this type of surgery are also discussed, including pericardial stimulation, vagal stimulation due to viscus traction, and direct atrial compression and other maneuvers that can cause hypotension and impaired cardiac filling. The differential diagnosis and treatment of intraoperative bradycardia, pulseless electrical activity (PEA), and cardiovascular collapse are reviewed. Finally, the importance of proper anesthesiologist’s vigilance, anticipation and planning, and OR team communication and dynamics in facilitating a good outcome are discussed.