Vagotonia and cardiac arrest during spinal anesthesia.

Abstract

SUDEN cardiac arrest during spinal anesthesia can occur in otherwise healthy patients. 1-6 Although respiratory depression secondary to excessive sedation is responsible in some cases, sudden cardiac arrest can occur without overt signs of respiratory depression in hemo-dynamically stable patients. Vasovagal reactions have been reported to cause cardiac arrest during spinal and epidural anesthesia. 5,6 Increased vagal tone, or vagotonia, is present in approximately 7% of the population. 7 Such individuals frequently have a history of recurrent reactions precipitated by emotional or physical stress. Vagotonic manifestations can include nausea, sweating, pallor, bradycardia, hypotension, and syncope. 7,8 If a patient who is prone to have vasovagal reactions is exposed to emotional stress during spinal anesthesia, what might otherwise be a benign or transient reaction may progress to cardiac arrest Two incidents of syncope and asystole, during two separate spinal anesthetics, are described in a patient with a history of recurrent vasovagal reactions.