Weaning-Related Shock in Patients With ECMO: Incidence, Mortality, and Predisposing Factors

Factors Influencing Successful Weaning From Venoarterial Extracorporeal Membrane Oxygenation: A Systematic Review

With advancements in extracorporeal life support (ECLS) technologies, venoarterial extracorporeal membrane oxygenation (VA-ECMO) has emerged as a crucial cardiopulmonary support mechanism. This review explores the significance of VA-ECMO system configuration, cannulation strategies, and timing of initiation. Through an analysis of medication management strategies, complication management, and comprehensive preweaning assessments, it aims to establish a multidimensional evaluation framework to assist clinicians in making informed decisions regarding weaning from VA-ECMO, thereby ensuring the safe and effective transition of patients.

Comparison of Conventional Methods with Pump-Controlled Retrograde Trial off for Weaning Adults with Cardiogenic Shock from Veno-Arterial Extracorporeal Membrane Oxygenation

Background

Pump-controlled retrograde trial off (PCRTO) is a safe, simple, and reversible method for weaning patients from veno-arterial extracorporeal membrane oxygenation (VA-ECMO). However, few studies have compared PCRTO to conventional weaning methods. This retrospective study aimed to compare PCRTO to non-PCRTO methods.

Methods

This study included patients who were weaned from VA-ECMO from January 2016 to December 2022 at our medical center. Demographic data, ECMO management, ECMO complications, survival to discharge, and cardiogenic shock after VA-ECMO weaning were compared between the 2 groups.

Results

Seventy patients who were weaned from VA-ECMO using PCRTO and 85 patients who were weaned with conventional methods were compared. Patient characteristics were not significantly different between the 2 groups. The rate of survival to discharge was significantly higher in the PCRTO group than in the non-PCRTO group (90% vs. 72%, p=0.01). The rates of freedom from all-cause mortality at 10, 30, and 50 days after weaning from ECMO were 75%, 55%, and 35% in the non-PCRTO group and 62%, 60%, and 58% in the PCRTO group, respectively (p=0.1). The incidence of cardiogenic shock after weaning from VA-ECMO was significantly higher in the non-PCRTO group (16% vs. 5%, p=0.04). In logistic regression analysis, PCRTO was a significant factor for survival to discharge (odds ratio, 2.42; 95% confidence interval, 1.29-5.28; p=0.02).

Conclusion

Compared to conventional methods, PCRTO is a feasible and reversible method, and it serves as a useful predictor of successful VA-ECMO weaning through a preload stress test.

Feasibility of pump-controlled retrograde trial off in weaning from veno-arterial ECMO in adults-A single-center case series

BACKGROUND

Various strategies of weaning V-A ECMO have been described. PCRTO is a weaning technique which involves serial decremental pump revolutions until a retrograde flow from the arterial to venous ECMO cannula is achieved. It has been reported as a feasible weaning strategy in the pediatric population, but its application in adults has not been widely reported.

METHODS

This was a case series including all adult patients who underwent PCRTO during weaning from V-A ECMO at a tertiary ECMO center between January 2019 and July 2021. The primary end point was the successful weaning from V-A ECMO support.

RESULTS

A total of 57 runs of PCRTO in 36 patients were analyzed-45 (78.9%) of the trials were concluded successfully. The median retrograde blood flow rate during PCRTO was 0.6 ± 0.2 L/min, and the median duration of each PCRTO was 180 (120-240) min. Of the 35 patients who had at least one session of successful PCRTO, 31 (88.6%) were ultimately weaned from ECMO. There were no major complications from PCRTO including systemic or circuit thrombosis.

CONCLUSIONS

PCRTO is a feasible strategy for assessing readiness for weaning from V-A ECMO with a low risk of adverse events and high rate of predicting eventual successful ECMO decannulation. Further investigation including comparison with alternative weaning strategies in prospective studies is required to confirm the approach.

Levosimendan in patients undergoing extracorporeal membrane oxygenation after cardiac surgery: an emulated target trial using observational data

BACKGROUND

Retrospective cohorts have suggested that levosimendan may facilitate the weaning of veno-arterial extracorporeal membrane oxygenation (VA-ECMO). We therefore studied this clinical question by emulating a randomized trial with observational data.

METHODS

All patients with refractory postcardiotomy cardiogenic shock and assisted with VA-ECMO, admitted to a surgical intensive care unit at La Pitié-Salpêtrière Hospital between 2016 and 2019, were eligible. To avoid immortal-time bias, we emulated a target trial sequentially comparing levosimendan administration versus no levosimendan administration in patients treated with VA-ECMO. The primary outcome was time to successful ECMO weaning. The secondary outcomes were 30-day and 1-year mortality. We performed a multivariable analysis to adjust for confounding at baseline.

RESULTS

Two hundred and thirty-nine patients were included in the study allowing building a nested trials cohort of 1434 copies of patients. No association of levosimendan treatment and VA-ECMO weaning was found (HR = 0.91, [0.57; 1.45], p = 0.659 in multivariable analysis), or 30-day mortality (OR = 1.03, [0.52; 2.03], p = 0.940) and 1-year mortality (OR = 1.00, [0.53; 1.89], p = 0.999).

CONCLUSIONS

Using the emulated target trial framework, this study did not find any association of levosimendan treatment and ECMO weaning success after postcardiotomy cardiogenic shock. However, the population of interest remains heterogeneous and subgroups might benefit from levosimendan.

Cause of In-Hospital Death After Weaning from Venoarterial-Extracorporeal Membrane Oxygenation

PURPOSE

A survival gap between weaning from venoarterial-extracorporeal membrane oxygenation (VA-ECMO) and the hospital discharge has been consistently reported. The aim of this study is to investigate the clinical features of patients who underwent successful VA-ECMO decannulation at our institution and to identify the major contributors responsible for adverse outcomes.

METHODS

We retrospectively reviewed all patients supported with VA-ECMO in our institution between January 2013 and June 2020. Only patients that survived VA-ECMO and underwent successful decannulation were included and dichotomized based on survival to hospital discharge: non-survivors versus survivors. The primary study outcome was the cause of death after successful VA-ECMO decannulation.

RESULTS

Of the 262 adult patients who underwent VA-ECMO decannulation, 72 (27.5%) patients did not survive to hospital discharge. Non-survivors were older (62 vs. 54 years, p < 0.001) and suffering from many pre-existing comorbidities. Pneumonia and sepsis were the most frequent infectious complication and almost twice as likely in non-survivors. Major causes of death were: cardiovascular (31.9%), infections (25.0%) and neurological (20.8%). The survival curve demonstrated that 51.4% of our patients died within 8 days after decannulation. Multivariate analysis identified older age, central venous cannulation, pulmonary bleeding and infection, dialysis after VA-ECMO, sepsis, and ischemic stroke (OR = 7.86, 95% CI: 2.76-2.43, p < 0.001) as factors significantly predisposing to patients' death.

CONCLUSION

In our study, one-third of patients decannulated off VA-ECMO did not survive to hospital discharge due to end-stage heart failure, infections or neurological injury. The first 8 post-decannulation days were recognized as a critical period where thorough strategies to prevent acquired infections and cautious support of end-organ function should be warranted. Future large-scale trials are needed to confirm our results.

Levosimendan in venoarterial ECMO weaning. Rational and design of a randomized double blind multicentre trial

AIMS

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly being used in circulatory failure. The main indications are cardiogenic shock, post-cardiotomy cardiac failure, and refractory cardiac arrest. However, VA-ECMO weaning is particularly challenging, and weaning failure is reported to be as high as 50%, with increased related mortality. Levosimendan is a novel long acting effect inodilator used in cardiogenic shock and terminal heart failure decompensation. Levosimendan use in VA-ECMO patients seems to reduce weaning failure regardless of the initial aetiology and to reduce mortality when administrated early after VA-ECMO initiation. However, studies are limited to retrospective analyses and reported case series. The aim of the WEANILEVO trial is to evaluate whether administration of levosimendan before VA-ECMO weaning is associated with a reduced rates of weaning failure and recourse to other temporary circulatory support.

METHODS AND RESULTS

WEANILEVO is a randomized, prospective, multicentre, double-blind, parallel-group, controlled trial. One hundred eighty patients will be enrolled if they had acute circulatory heart failure treated with VA-ECMO and for whom weaning is expected within 48 h. The study drugs are either levosimendan (0.2 μg/kg/min for 24 h) or a placebo. The primary endpoint of the trial is the absence of VA-ECMO weaning, recourse to another VA-ECMO, or other temporary circulatory assistance or death within 7 days of VA-ECMO weaning.

CONCLUSIONS

Levosimendan use in VA-ECMO appears to be beneficial for reducing weaning failure and mortality. The results of WEANILEVO should significantly influence decisions regarding the use of levosimendan for VA-ECMO weaning.