# Inflammatory Cytokines as Early Predictors of Weaning Failure From Extracorporeal Life Support

## TL;DR

This study shows that IL8 levels measured within the first 24 hours of ECLS can predict whether a patient will fail to wean off life support, offering a potential early biomarker for clinical decision-making.

## Contribution

The study identifies IL8 as a novel early predictor of ECLS weaning failure, with higher accuracy than other cytokines like IL6 and TNF-α.

## Key findings

- IL8 levels after 24 hours showed the highest predictive accuracy (AUC = 0.73) for ECLS weaning failure.
- A decline in IL8 levels during the first 24 hours was associated with successful weaning (p = 0.008).
- IL8 and IL6 levels were reliable early predictors of ECLS weaning failure, particularly in specific subgroups like septic shock and pulmonary embolism.

## Abstract

Weaning from extracorporeal life support (ECLS) in patients with refractory shock still remains a complex decision. Despite considerable advances in ECLS management, reliable biomarkers to predict weaning success are still not available. Inflammatory cytokines including interleukin‐6 (IL6), interleukin‐8 (IL8), and tumor necrosis factor‐alpha (TNF‐α) may reflect systemic immune response and have been proposed as potential predictors of deterioration or recovery.

A retrospective, single‐center study analyzed 809 patients with ECLS between 2012 and 2024. Serum levels of IL6, IL8, and TNF‐α were measured before ECLS and 24 h after initiation. Receiver operating characteristic (ROC) analysis and subgroup comparisons between clinical phenotypes were used to assess the cytokine predictive value.

Weaning was achieved in 66.9% of patients. IL8 levels after 24 h demonstrated the highest predictive accuracy for weaning failure (area under the curve AUC = 0.73), outperforming IL6 and TNF‐α. The decline of IL8 levels during the first 24 h was associated (p = 0.008) with successful weaning. Subgroup analysis revealed that the predictive values of IL6 and IL8 were pronounced in patients with pulmonary embolism (AUC = 0.72, IL6) and septic shock (AUC = 0.77, IL8), with significantly elevated cytokine levels. Patients with structural heart disease (AUC = 0.85, IL6) and ventricular arrhythmias (AUC = 0.82, IL6) showed cytokine levels comparable to the whole cohort and a better prediction.

Among the evaluated cytokines, IL8 exhibited the strongest predictive benefit for weaning failure, especially on Day 1. Due to its early clearance dynamics, it may be a useful parameter in the appropriate clinical situation to achieve a better outcome.

Levels of IL‐8 and IL‐6 and their dynamics are reliable early predictors of ECLS weaning failure.