The Science Journal of the American Association for Respiratory Care
This case presentation demonstrates the prophylactic use of venous-arterial extracorporeal membrane oxygenation (VA ECMO) during a high-risk interventional cardiac catheterization. The patient was a 2.5 kilogram, 37 week gestational age (WGA) twin B female diagnosed in utero at 29 WGA with Ebstein's anomaly.1 Her APGAR scores were 6 (1 min) and 8 (5 min), and she was admitted to a level III nursery where she was intubated and started on prostaglandin E1. She was desaturated at the time of transfer to our cardiac ICU, and inhaled nitric oxide (NO) was started as a selective pulmonary vasodilator. After 24 hours she developed episodes of supraventricular tachycardia (SVT) due to reentry over an uncommon type of accessory conduction pathway known as a Mahaim fiber. These episodes were accompanied by severe hypotension, at times requiring cardiac massage, and treatment with the antiarrhythmic agents digoxin, procainamide, and amiodarone all failed to control the SVT. The best solution was to perform a radiofrequency catheter ablation of the Mahaim fiber. This was problematic because of the patient's small size, the severity of hypotension in tachycardia, and the fact that pathway mapping could only be performed during SVT. VA ECMO was considered to be a viable means of support during this potentially lengthy and difficult procedure. Under controlled circumstances in the ICU, she was cannulated with a #10 Biomedicus venous cannula in the right internal jugular vein and a #8 Biomedicus arterial cannula in the right common carotid artery. The flowrate was 110cc/kg/min and the sweep gas 3/4L carbogen and 1/4L oxygen. Transport on ECMO to and from the catheterization laboratory was uneventful, and pathway mapping and ablation were arduous but successful. There were no complications on ECMO and she was decannulated after 72 hours. SVT was not inducible in follow-up testing. She was extubated 9 days later to nasal cannula NO and is presently home without obvious sequelae. In summary, while ECMO is traditionally used to salvage patients with pulmonary and/or cardiac failure that is refractory to conventional therapies, we used ECMO proactively in this neonate to prevent a decompensation during a cardiac procedure known to carry high risks.
1. Celermajer, DS, Bull, C, et al. J Am Coll Cardiol 1994;23;170-6.