87: Extracorporeal Membrane Oxygenation in Pediatric Cardiac Care

Introduction

From the earliest days, advances in extracorporeal membrane oxygenation (ECMO) have been linked to advances in cardiopulmonary bypass (CPB) and repair of congenital cardiac malformations. Since C. Walton Lillihei¹ first employed the technique of controlled cross-circulation using the patient’s parent, efforts to perfect cardiopulmonary support have transitioned from the operating room to the intensive care unit. In the intervening years, every facet of CPB has been studied and refined. Improvements in these techniques have afforded the surgeon the opportunity to tackle the most complex anatomic anomalies in even the smallest babies. Likewise, advances in extracorporeal support (ECLS) methods have led clinicians to expand their clinical indications and implementation in the ICU. However, despite the fact that the notion and use of extracorporeal circulation originated in the cardiac surgical suite, heart disease was, until the last decade or so, usually a contraindication for ECMO. Early experience in adults was discouraging,² with better success reported in the care of newborns with respiratory failure.³ Extension to include older infants and children with respiratory failure followed.⁴

Pediatric cardiac ECMO, as it has come to be known, was first reported by Soeter and colleagues in 1973. He described the successful application of ECMO in a 4-year-old girl following repair of tetralogy of Fallot, who was weaned from support in 48 hours and discharged home 11 days later.⁵ By the late 1980s and early 1990s, cardiac ECMO gained traction in the pediatric cardiac community, as many large centers reported favorable outcomes with postoperative support. With experience, refinement, and successes, cardiac ECMO has made the transition from “rescue” therapy, to “therapeutic” or even “preventive” management. Coincident with advances in pharmacologic and mechanical ventilatory support strategies for respiratory failure, the number of ECMO runs for the cardiac population has steadily increased as a proportion of the Extracorporeal Life Support Organization (ELSO) Registry (Fig. 87-1). In this chapter, we take a comprehensive look at cardiac ECMO, with attention to the different types (venoarterial or venovenous), their relative indications, and their respective advantages, disadvantages, and outcomes. In addition, we discuss the myriad equipment options and also review the physiology of ECMO and principles of clinical application. Last, we consider new opportunities and indications for mechanical circulatory support.

Venoarterial Extracorporeal Membrane Oxygenation

In simplest terms, venoarterial ECMO (VA-ECMO) consists of taking deoxygenated blood from the venous circulation, oxygenating it, and then pumping it back into the arterial circulation. How this is accomplished depends on individual and institutional experience and preference. The obvious benefit is that the patient’s entire cardiorespiratory system is bypassed, thereby ensuring adequate end-organ oxygenation despite respiratory and circulatory collapse. Ideally, the brain, kidneys, ...