Neonatal Critical Care- ECMO

By; Anna Kuruc, Alex Muller, Lauren Harnois, Urvinder Kaur

“Within 30 minutes of her arrival to the ED, Janet suffered cardiopulmonary arrest. She was successfully resuscitated, but her condition was tenuous. She did not respond to conventional management of septic shock 12 hours after initiation of therapy. Consequently, the medical team was considering ECMO.
Do you think ECMO should be offered to Janet? Why, or why not.”

     In medicine, it is always our best intention to treat the underlying cause of cardiopulmonary arrest quickly and effectively to reduce long-term neurological impairments. In Janet’s situation described above, to successfully treat septic shock, mechanical ventilation should be implemented immediately to reduce the work of breathing and oxygen consumption. Central venous oxygen saturation should be used as a surrogate for both tissue perfusion and blood lactate.¹ Vascular volume needs to be restored for adequate circulating blood volume with administration of 20 ml/kg of fluid even after shock. However, since Janet suffered cardiopulmonary arrest, additional fluids may in fact impair the ability of the myocardium to maintain cardiac output.² If Janet still remains in shock after conventional treatments, supportive therapy should be considered. We would agree with the medical team that initiating extracorporeal membrane oxygenation (ECMO) is a reasonable intervention to address the progressive respiratory and cardiac failure, which will ultimately lead to death without treatment.

         The main principle behind ECMO is to allow the organs time to rest, aiding in recovery. It is very important to realize ECMO does not treat the underlying condition; it merely takes over the work of the heart and lungs, allowing the body to rest while the medical team treats the illness.³ ECMO is a life-saving intervention that can be used for several days; however, it is very expensive and requires considerable resources. Studies show that early introduction of ECMO is related to better clinical outcomes and hospital survival. Therefore, the first intuitive judgment should be to initiate ECMO in emergency situations when conventional therapies fail. ⁴

         ECMO is an invasive treatment in which blood is drained from the venous system using a pump to circulate blood through an artificial lung and reinfused to the patient through either the pulmonary or systemic circulation. The classic venoarterial (VA) ECMO provides support to the lungs and heart, which involves surgically inserting perfusion cannulas into a right internal jugular vein and right common carotid artery. However, for profound septic shock, central cannulation is performed by a cardiac surgeon and involves inserting a cannula into the heart directly via transthoracic access (e.g., right atrium drainage and ascending aorta reinfusion). Deoxygenated venous blood is emptied from the patient and fully oxygenated blood is artificially pumped into the arterial system. Targeted flows are usually 1.5 L/kg/min in children under 10 kg and 2.4 L/min/m²  in children over 10 kg.⁴ In Janet’s case, ECMO will help bridge the period between recovery of the septic shock and cardiac failure by enabling restoration of adequate body oxygenation, and give us time to gain control over sepsis and antibiotic therapy. ⁵

        Complications during ECMO are usually related to equipment and technical issues. Bleeding is the main concern because it can occur at any surgical incision site.² Anticoagulation therapy is vital for the blood to flow through the circuit without any thrombus formations. Heparin is continuously infused into the circuit and anticoagulation is measured by the activated clotting time (ACT). The goal is to maintain an activated clotting time of 1.5-2 times normal, but for patients with significant bleeding clotting time will be reduced to 1.3-1.4 times normal.⁴ Adequate perfusion to the brain is essential to reduce disability impairments.

        Since 1972, ECMO has been used to treat critically ill patients with respiratory and cardiac failure. In a study of 239 children, 76% of patients with respiratory failure showed improved survival rates after being placed on ECMO between the years of 1973 to 2010. In 2010, a new generation of ECMO devices, ECMO2 was developed. This updated edition has become more automatic and user friendly, allowing it to be both understood and run by all licensed medical staff, decreasing the overall cost. ⁶ ECMO continues to be a vital intervention in today’s medical world, and without it, many lives might not have been saved.

 

Saving Henley’s Heart and Lungs: An ECMO Story | Cincinnati Children’s

 

References

1.    Farrell D, Nadel S. What’s New in Paediatric Sepsis. Curr Pediatr Rep 2016;4:1-5.
2.    Walsh, Brian K. Neonatal and Pediatric Respiratory Care. 4th ed. N.p.: Elsevier, 2015.
3.    Joffe AR, Lequier L, Robertson CM. Pediatric outcomes after extracorporeal membrane oxygenation for cardiac disease and for cardiac arrest: a review. ASAIO J 2012;58(4):297-310.
4.     MacLaren G, Butt W, Best D, Donath S, Taylor A. Extracorporeal membrane oxygenation for refractory septic shock in children: one institution’s experience. PEDIATR CRIT CARE MED 2007;8(5):447-451 5p.
5. Tsuneyoshi H, Rao V. The role of extracorporeal membrane oxygenation (ECMO) therapy in acute heart failure. Int Anesthesiol Clin 2012;50(3):114-122.
6.     Gray BW, Haft JW, Hirsch JC, Annich GM, Hirschl RB, Bartlett RH. Extracorporeal life support: experience with 2,000 patients. ASAIO J 2015;61(1):2-7.