Pulseless Electrical Activity and Perioperative Cardiac Arrest Due to Undiagnosed and Asymptomatic Hypothyroidism During Outpatient Surgery in an Adolescent.

Commonly identified risk factors for perioperative cardiac arrest in pediatric-aged patients include cardiac surgery, younger age, comorbid conditions including pulmonary hypertension and cyanotic congenital heart disease, and emergency surgery. Although medication-related etiologies formerly predominated, the elimination of halothane from anesthetic care has resulted in a shift in etiology to hemodynamic events related to blood loss or hyperkalemia associated with the rapid administration of blood products. Rarely, cardiac arrest can be sudden and unexpected without an identified pre-existing etiology in an otherwise apparently healthy patient.