Lung Injury Persists in ECMO Survivors

Neonates who receive extracorporeal membrane oxygenation (ECMO) for intractable respiratory failure experience lung injury lasting into later childhood, according to a report in the November issue of Pediatrics. “These children must be followed carefully through childhood and adolescence to ensure proper management of the respiratory sequelae of early life lung injury, ” said the senior investigator.

“We [previously] studied a group of infants later in the first year after birth who had had ECMO and another group who had indication for ECMO and survived though not treated with ECMO,” Dr. Arnold C. G. Platzker from University of Southern California Keck School of Medicine, Los Angeles, California told Reuters Health.

“We found that the ECMO group had much better lung compliance than the non-ECMO group. The present study was to determine whether the ECMO-treated patient would ultimately avoid any limitation of lung function at an age when lung development was complete.”

Among the 50 children who survived ECMO, residual volumes were higher, and forced expired volumes were lower during rest than among controls, Dr. Platzker and colleagues report. About half the children in the ECMO group had hyperinflation and airway obstruction.

Half the ECMO children had wheezing at some point in their lives, the study found, and one-third had experienced wheeze during the prior 12 months. A third of the ECMO children had physician-diagnosed asthma requiring treatment with bronchodilators and inhaled steroids.

During cardiopulmonary exercise testing, maximal ventilation was lower in the ECMO group than in controls, and 23% of the ECMO group had oxygen desaturation, the researchers note. Exercise-induced bronchospasm was more than twice as common in the ECMO group.

Children who required higher peak ventilator pressures and higher inspired oxygen concentrations after weaning from ECMO had lower FEV1 in this study, the report indicates, and longer neonatal hospitalization was associated with lower FEV1.

“The hypothesis for much of my work is that childhood antecedents for the majority of adult lung disorders begin very early after birth, when the structure of the lung is still undergoing development, cell-cell junctions are easily disrupted, and the chest wall is soft, providing little protection against over distension of the lung (with assisted ventilation),” Dr. Platzker explained.

“Early lung injury (neonatal respiratory illness + oxygen supplementation + positive pressure ventilation) leaves an indelible mark, resulting in injury to the developing lung which transcends infancy and childhood,” Dr. Platzker said. As well as the need for ongoing pulmonary health care, he said, “neurodevelopmental and auditory follow-up are also essential.”

Unfortunately, Dr. Platzker commented, “there are impediments to providing appropriate care for the survivor of severe neonatal respiratory illnesses. The major problem is the evolution of managed care, whose premise seems to be if the patient survives and does not have overt symptoms, no HMO-funded follow-up is necessary.”