Rescue therapy following failed conventional support of severe neonatal respiratory failure.
Review criteria for patient selection; timing of referral and type of extracorporeal membrane oxygenation (ECMO) support; routine ECMO procedures and management; weaning and discontinuation of ECMO; complications and outcomes.
ECMO is a modified form of cardiopulmonary bypass used to provide prolonged extracorporeal support to critically ill-term or near-term neonates with severe but potentially reversible respiratory and/or cardiac failure. Despite the complexity and risks associated with this modality, ECMO is an accepted and proven rescue therapy that has been routinely used for over two-and-a-half decades in neonates failing standard conventional treatments, including high-frequency ventilation (HFV) and inhaled nitric oxide (iNO). In the setting of life-threatening respiratory disease and persistent pulmonary hypertension (PPHN), ECMO allows for temporary lung rest by augmenting oxygenation and ventilation. If veno-arterial (VA) ECMO is selected, cardiovascular support is additionally provided, while veno-venous (VV) ECMO provides only respiratory support.
The Extracorporeal Life Support Organization (ELSO) provides an international registry that tracks neonatal ECMO cases. To date, over 27,000 neonates with respiratory failure have been treated with ECMO in the ELSO registry with an overall survival to discharge or transfer of 74%. Survival varies based on the severity of the underlying disease process range from 94% for neonates with a primary diagnosis of meconium aspiration syndrome to 51% with congenital diaphragmatic hernia (CDH). While VV ECMO is preferred and its use has increased in many centers over the past decade with improvements in circuit and cannula technology, VA ECMO continues to represent approximately two-thirds of cases historically.
In appropriately selected patients, the use of ECMO provides life-saving support, resulting in one additional survivor for every three to four neonates treated, without increasing morbidity. ECMO is most effective in mature neonates with severe reversible lung disease secondary to meconium aspiration, respiratory distress syndrome, PPHN, and/or pneumonia/sepsis. Although commonly used in newborns with CDH, the benefit of ECMO in this population remains less certain. For hemodynamically stable neonates with adequate cardiac function, VV ECMO is the modality of choice for neonatal respiratory failure.
Basic patient selection criteria for neonatal ECMO are well established, as outlined in Table 29.1. Low birth weight is considered a relative contraindication based on the technical limitations of cannulation. Corrected chronologic age should be taken into account, as this more accurately reflects bleeding risks in premature infants as compared to gestational age alone.
Surgical cannulation for VV ECMO typically requires a minimum weight of 2 kg given that the smallest dual-lumen VV cannula is 12 French, while VA single-lumen catheters are available in sizes ...