A Plea for Adoption of the Common ECLS Nomenclature

To the Editor: In a retrospective cohort study of adult patients with right ventricular failure requiring extracorporeal membrane oxygenation (ECMO), the authors compared outcomes of patients supported with a single-site, dual lumen cannula versus dual-site, single lumen cannulas. The authors found no significant difference in mortality between the two groups but concluded that there was a potential benefit in favor of the single-site, dual lumen cannulation configuration.1 In 2017, the Extracorporeal Life Support Organization (ELSO) assembled the nomenclature task force (NTF) comprised of experts from the international ELSO chapters. During the sixth EuroELSO meeting in Maastricht, The Netherlands, the ELSO-NTF developed a consensus document for extracorporeal life support (ECLS) nomenclature with the objective of creating a standardized method of describing cannulations to address the vague and inconsistent use of terms and abbreviations in contemporary ECLS literature.2,3 As newer ECMO cannulas, such as the LivaNova ProtekDuo (London, UK) and the Spectrum Medical Dual Lumen Cannula (Gloucester, UK), have gained adoption, and additional modes and configurations have been described that account for ECMO blood return into the pulmonary artery via a peripherally inserted cannula.4 In their publication, Ritter et al. use the nomenclature “C-PA” to denote a single-site, dual lumen cannula with tip placement and blood return in the pulmonary artery, and “V-PA” to denote a dual-site, single lumen cannula configuration with blood return in the pulmonary artery.1 In other publications, the same configurations have described using different terminology such as “oxyRVAD.”2,4 We find this nomenclature to be confusing as the author’s choice of “C-PA” is equivalent to what ELSO has acknowledged as venopulmonary (VP) mode in a configuration that should be denoted as “(dl)V-P.”4,5 Likewise, the authors’ use of the abbreviation “V-PA” is equivalent to what ELSO has denoted as “V-P,” or more specifically “Vf-Pj.”4 Furthermore, “PA” has been designated as an abbreviation to be used when a cannula is placed in the pulmonary artery during central ECMO cannulation and therefore should not be used when describing a peripheral configuration.2 Despite publication of recommended ECLS nomenclature, the use of nonstandardized and novel nomenclature continues to occur in the ECLS literature. The poor adoption of this standardized language presents ongoing difficulties in following, searching, and comparing the available literature. As the trajectory of ECLS publications continues to increase, we think it is extremely important to insist as a scientific community that a common, consensus-based language be used in scientific publications. As such, we implore authors to familiarize themselves with the ELSO Maastricht Treaty for Nomenclature in ECLS and begin using standardized nomenclature in their scholarly work. We posit that widespread adoption of standardized nomenclature in studies of ECLS likely depends on the support and expectations of editorial staff and reviewers of journals that frequently publish such studies. Finally, we submit that ASAIO Journal, in particular, has both an opportunity and responsibility to its readership to spearhead this change in practice.