Pump-controlled retrograde trial off in veno-arterial extracorporeal membrane oxygenation weaning: a scoping review of physiological rationale, protocol heterogeneity, and clinical application
File(s)
Published online version
Author(s)
Type
Journal Article
Abstract
Background
Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is increasingly used for refractory cardiogenic shock; however, strategies to assess readiness for decannulation remain poorly defined. Although pump-controlled retrograde trial off (PCRTO) is a novel weaning assessment, its conceptual basis and clinical role remain unclear. This scoping review aimed to map the existing evidence on PCRTO in V-A ECMO, focusing on its methodological definition, implementation, monitoring strategies, and reported outcomes, and to identify key knowledge gaps.
Methods
We conducted a scoping review following the established methodological guidelines and Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews checklist. Using the Patient–Concept–Context framework, we included studies involving neonatal, pediatric, and adult patients supported with V-A ECMO who underwent PCRTO. MEDLINE, Embase, CENTRAL, and ClinicalTrials.gov were searched from inception without language or date restrictions. Two reviewers (YI and HM) independently screened studies and extracted data using a standardized charting form, and the findings were descriptively summarized.
Results
Twenty-one studies were included, predominantly case reports and case series, with limited observational data. PCRTO protocols substantially varied across studies, including differences in retrograde flow targets (commonly −0.5 to −1.0 L/min or −5 to −10 mL/kg/min), trial duration (minutes to several hours), and circuit management. Monitoring approaches were heterogeneous and frequently incorporated hemodynamic, metabolic, and echocardiographic parameters. Successful weaning was commonly reported; however, definitions of outcome and adverse events were inconsistent.
Conclusions
PCRTO is a conceptually distinct weaning assessment in V-A ECMO that may provide additional physiological information beyond conventional flow reduction, particularly in evaluating right ventricular reserve. However, its definition, optimal protocol, and clinical effectiveness remain to be established. Further studies are required to standardize its physiological framework and clarify its role in V-A ECMO weaning.
Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is increasingly used for refractory cardiogenic shock; however, strategies to assess readiness for decannulation remain poorly defined. Although pump-controlled retrograde trial off (PCRTO) is a novel weaning assessment, its conceptual basis and clinical role remain unclear. This scoping review aimed to map the existing evidence on PCRTO in V-A ECMO, focusing on its methodological definition, implementation, monitoring strategies, and reported outcomes, and to identify key knowledge gaps.
Methods
We conducted a scoping review following the established methodological guidelines and Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews checklist. Using the Patient–Concept–Context framework, we included studies involving neonatal, pediatric, and adult patients supported with V-A ECMO who underwent PCRTO. MEDLINE, Embase, CENTRAL, and ClinicalTrials.gov were searched from inception without language or date restrictions. Two reviewers (YI and HM) independently screened studies and extracted data using a standardized charting form, and the findings were descriptively summarized.
Results
Twenty-one studies were included, predominantly case reports and case series, with limited observational data. PCRTO protocols substantially varied across studies, including differences in retrograde flow targets (commonly −0.5 to −1.0 L/min or −5 to −10 mL/kg/min), trial duration (minutes to several hours), and circuit management. Monitoring approaches were heterogeneous and frequently incorporated hemodynamic, metabolic, and echocardiographic parameters. Successful weaning was commonly reported; however, definitions of outcome and adverse events were inconsistent.
Conclusions
PCRTO is a conceptually distinct weaning assessment in V-A ECMO that may provide additional physiological information beyond conventional flow reduction, particularly in evaluating right ventricular reserve. However, its definition, optimal protocol, and clinical effectiveness remain to be established. Further studies are required to standardize its physiological framework and clarify its role in V-A ECMO weaning.
Date Issued
2026-09-16
Date Acceptance
2026-09-12
Citation
Critical Care, 2026
ISSN
1364-8535
Publisher
Springer Science and Business Media LLC
Journal / Book Title
Critical Care
Copyright Statement
© The Author(s) 2026 Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
Publication Status
Published online
Date Publish Online
2026-09-16