Pushing the boundaries for the use of ECMO in acute hypoxic respiratory failure

Excerpt

Extracorporeal membrane oxygenation (ECMO) has an established place in the treatment of acute cardiorespiratory failure in children based on over 25 years of accumulated clinical experience. The Extracorporeal Life Support Registry (ELSO) database now contains outcome data on over 20,000 patients with survival rates varying between more than 80% in neonates to 40–50% in older children and adults. In 1996 a randomized trial in the United Kingdom showed better outcomes in neonates with severe respiratory failure treated with ECMO compared to conventional ventilation [1]. There has been no equivalent study in older children, and although ECMO has been used for the treatment of adults with ARDS since the 1970s, two randomized trials have failed to show superiority to standard treatment [2, 3]. Despite this there has been encouraging single-centre experience of the successful use of ECMO as rescue therapy in adults with ARDS and following lung transplantation [4, 5, 6, 7, 8]. This, combined with criticisms of study design in the original trials, has prompted the launching of a further randomized controlled trial on the use of ECMO in adults with acute hypoxic respiratory failure (AHRF) in the United Kingdom. Despite the lack of high-level efficacy data in children there have been increasing numbers placed on ECMO at a time when neonatal ECMO numbers are falling, due to changes in ventilation strategy which now includes pressure limitation and the use of high-frequency oscillatory ventilation and inhaled nitric oxide. Advances in oxygenator technology have extended the life of ECMO circuits and has led to a reduction in complications associated with bleeding. This has emboldened people to push the boundaries of ECMO into areas such as AHRF associated with hematological malignancy and bone marrow transplantation, which were previously thought to be contraindications [9, 10]. …