Association of early changes in arterial carbon dioxide with acute brain injury in adult patients with extracorporeal membrane oxygenation: A ten-year retrospective study in a German tertiary care hospital

Purpose

To assess the association between fluctuations of arterial carbon dioxide early after start of extracorporeal membrane oxygenation (ECMO) with intracranial hemorrhage (ICH) or ischemic stroke (IS).

Materials and methods

This single-center retrospective study included patients who required ECMO for circulatory or respiratory failure between January 2011 and April 2021 and for whom a cerebral computed tomography (cCT) scan was available. Multivariable logistic regression models were fitted to evaluate the association between the relative change of arterial carbon dioxide (RelΔPaCO₂) and ICH, IS or a composite of ICH, IS, and mortality.

Results

In 618 patients (venovenous ECMO: n = 295; venoarterial ECMO: n = 323) ICH occurred more frequently in patients with respiratory failure (19.0%) compared with patients with circulatory failure (6.8%). Conversely, the incidence of IS was higher in patients with circulatory failure (19.2%) compared with patients with respiratory failure (4.7%). While patients with ECMO for respiratory failure were more likely to have ICH (OR 3.683 [95% CI: 1.855;7.309], p < 0.001), they had a lower odds for IS (OR 0.360 [95%CI: 0.158;0.820], p = 0.015) compared with patients with circulatory failure. There was no significant association between RelΔPaCO₂ and ICH or IS.

Conclusions

Irrespective of the indication for ECMO, we did not find a significant association between the relative change in PaCO₂ early after ECMO initiation and acute brain injury. Aside from early PaCO₂ decline at cannulation, future studies should address fluctuations of PaCO₂ throughout the course of ECMO support and their effect on acute brain injury.