Apnea Test on Extracorporeal Membrane Oxygenation: Step Forward with Carbon Dioxide

Apnea test must be performed to confirm brain death in patients meet clinical criteria. But the increment of carbon dioxide is generally not achievable because of the diminished production of carbon dioxide and additional sweep in extra corporeal membrane oxygenation (ECMO). We report three children with congenital heart disease treated with ECMO and had brain death during follow-up. All met clinical criteria but apnea test cannot be achieved in classical way because of prolonged duration and hemodynamic compromise. Therefore, we used external carbon dioxide to achieve desired levels of oxygen and carbon dioxide safely. Because of the lack of protocols for pediatric patients on ECMO, apnea test with exogenous carbon dioxide may be a reliable and rapid test in such patients. Especially cardiac patients, in whom classical apnea test can cause rapid deterioration, exogenous carbon dioxide may serve as an alternative.