ECMO – Inside Pediatrics

New hope for neonates with severe congenital kidney disease

_{ECMO in use at Children’s of Alabama (file photo)}

Almost a decade ago, Nephrology specialists at Children’s of Alabama embarked on a journey to improve outcomes in neonates with severe congenital kidney disease by adapting the Aquadex machine, a small extracorporeal circuit used for adults with heart failure. Traditionally, extracorporeal membrane oxygenation (ECMO) was deemed unsuitable for this population due to perceived nonviability. In 2016, at the family’s request, a baby with severe congenital kidney failure and severe respiratory failure was placed on ECMO to be given a chance at life. The baby also required kidney support therapy (KST) to survive. After receiving a kidney transplant at age 2, the child now goes to school, plays sports, sings and dances.

Since 2016, of the 31 neonates with congenital kidney failure who were admitted to the Children’s neonatal intensive care unit (NICU), five required ECMO support and KST in the first two weeks of life. In February 2024, Kara Short, MSN, CRNP, CPNP-PC, David Askenazi, M.D., MSPH, and others published a case report in Pediatrics, highlighting the complex treatment of the five babies and the journey to NICU discharge for the four survivors. This study challenges the previous norms and conventions that these babies had no chance at life.

Congenital kidney failure poses unique challenges to neonates, affecting not only renal homeostasis but also respiratory integrity. Diagnoses among the five patients in the study included posterior urethral valves, bilateral renal dysplasia and autosomal recessive polycystic kidney disease. Despite gestational age ranging from 35.6 to 37.1 weeks and birth weight from 2,740 grams to 3,140 grams, all five patients received KST by postnatal day seven. Additionally, they were all placed on ECMO within the first nine postnatal days due to severe respiratory distress after being unresponsive to conventional interventions.

Four of the five patients survived and are thriving today. Pulmonary hypertension resolved in each survivor, with three requiring no oxygen support and one needing only nocturnal oxygen. Three survivors underwent successful kidney transplants, while one awaits transplant evaluation. This challenges the traditional notion of reflexively assigning nonviability to neonates with congenital kidney failure and severe pulmonary complications.

This research highlights the significance of ECMO and kidney support therapy in mitigating the adverse effects of pulmonary edema, uremia and electrolyte complications. The use of a filter through the ECMO circuit—to perform continuous venovenous hemodialysis (CVVHD), continuous venovenous hemofiltration (CVVH) with the Aquadex machine, peritoneal dialysis and intermittent hemodialysis—showcases the synergism and need for different approaches to manage these complex cases.

Managing congenital kidney failure requires a multidisciplinary approach involving neonatology, nephrology, surgery and multiple ancillary divisions. “As healthcare providers, we all bring something to the table,” Askenazi said. “The families need clear, concise information so they can understand their options when making treatment decisions. Our job is to develop programs, systems and plans to help those kids have the best chance at life.”

The families of the neonates faced challenging decisions, including the choice of full medical support or palliative care. Despite the complexity and potential extended NICU stay, all five families opted for full medical support. Clear communication, counseling and informed decision-making were instrumental when families made medical decisions about their baby’s care.

The successful outcomes of neonates with congenital kidney failure undergoing ECMO challenge previous assumptions of nonviability. Meticulous ECMO, respiratory, nutritional and kidney support therapies are essential to favorable long-term results. Further investigation is needed to define the optimal strategies to improve outcomes in severe congenital kidney disease cases. “We want to share this information with other programs to let them know that these kids have a chance at life; what we learned in this very small cohort is that these lungs can develop and grow if given a chance,” Short said.

“When thinking about the future, we’re asking ourselves: How can we get the very best technology to care for these babies? How can we help other programs improve so they can better care for their kids? How do we ensure that families are counseled with all viable options in an honest and comprehensive way?” Askenazi said. “We will continue to make progress. We have recently received a grant from the National Institutes of Health (NIH) to partner with industry to make a better device for neonates. We recognize that we must continue to educate our colleagues across the U.S. and the world about what we have learned from these miracle babies.”

February 5, 2024 by childrensal

Cardiology

The benefits of bivalirudin during ECMO care

_{A new study is shaking up the standard practice of using heparin for anticoagulation in ECMO patients.}

Anticoagulation therapy during extracorporeal membrane oxygenation (ECMO) has long relied on heparin, but a groundbreaking multicenter study co-authored by Jonathan Byrnes, M.D., medical director of cardiac ECMO at Children’s of Alabama, shows the benefits of replacing heparin with bivalirudin.

Bivalirudin isn’t a new drug, but its rise in use in pediatric ECMO stems from successes in pediatric ventricular assist devices (VADs). With earlier stroke rates as high as 25–30% on VADs using heparin, the transition to bivalirudin brought about a remarkable reduction, dropping the stroke rate to 5–8%. This significant improvement in neurological outcomes sparked interest in applying bivalirudin more extensively in ECMO settings.

The study, spearheaded by Mohammed Hamzah, M.D., of Cleveland Clinic Children’s Hospital, diverged from past practices of individual center decision-making. Instead, six medical centers collaborated, aiming to analyze outcomes through a case-matched lens, minimizing variability across patients requiring ECMO. The study’s cooperative nature across multiple centers necessitated remarkable coordination.

One of the study’s key findings, according to Byrnes, is that patients on bivalirudin exhibited lower mortality rates than those on heparin. Intriguingly, despite higher PTT levels in bivalirudin patients, they experienced less bleeding and fewer thrombotic incidents in the ECMO circuit. This hints at bivalirudin’s inherent benefits, possibly enhancing biocompatibility. “It seems that there’s something intrinsic to bivalirudin that allowed for better biocompatibility of the patient’s blood to the ECMO circuit,” Byrnes said.

The impact of this study extends far beyond the academic realm. At Children’s of Alabama, the findings suggest potential benefits such as reduced bleeding, fewer transfusions and lower mortality rates for ECMO-supported patients. However, as Byrnes noted, the retrospective nature of the study necessitates a randomized controlled trial to solidify these outcomes and effectively influence the standard of care.

Plans for a prospective trial are underway, aiming for a randomized approach coordinated through the Extracorporeal Life Support Organization (ELSO). This prospective study could validate the retrospective findings, potentially reshaping protocols for anticoagulation during ECMO.

Despite the excitement surrounding the study’s outcomes, Byrnes emphasized the need for caution. While retrospective data suggests bivalirudin’s superiority, a randomized trial is crucial to establish this definitively. Prospective data will unveil any center-specific confounders that might have influenced the study’s retrospective findings.

Byrnes underscored the significance of these findings and the hope for future randomized controlled trials. The study’s retrospective nature lays a robust foundation, but prospective data will offer irrefutable evidence to guide clinical practice, leading to a potential paradigm shift in anticoagulation therapy that may result in improved patient care and outcomes.

January 25, 2024 by childrensal