Intra-aortic balloon pump protects against hydrostatic pulmonary oedema during peripheral venoarterial-extracorporeal membrane oxygenation

Background: Increased left ventricular afterload during peripheral venoarterial-extracorporeal membrane oxygenation (VA-ECMO) support frequently causes hydrostatic pulmonary oedema. Because physiological studies demonstrated left ventricular afterload decrease during VA-ECMO assistance combined with the intra-aortic balloon pump (IABP), we progressively changed our standard practice systematically to associate an IABP with VA-ECMO. This study aimed to evaluate IABP efficacy in preventing pulmonary oedema in VA-ECMO-assisted patients. Methods: A retrospective single-centre study. Results: Among 259 VA-ECMO patients included, 104 received IABP. Weinberg radiological score-assessed pulmonary oedema was significantly lower in IABP+ than IABP– patients at all times after ECMO implantation. This protection against pulmonary oedema persisted when death and switching to central ECMO were used as competing risks (subhazard ratio 0.49, 95% confidence interval (CI) 0.33–0.75; P<0.001). Multivariable analysis retained IABP as being independently associated with a lower risk of radiological pulmonary oedema (odds ratio (OR) 0.4, 95% CI 0.2–0.7; P=0.001) and a trend towards lower mortality (OR 0.54, 95% CI 0.29–1.01; P=0.06). Finally, the time on ECMO free from mechanical ventilation increased in IABP+ patients (2.2±4.3 vs. 0.7±2.0 days; P=0.0003). Less frequent pulmonary oedema and more days off mechanical ventilation were also confirmed in 126 highly comparable IABP+ and IABP– patients, propensity score matched for receiving an IABP. Conclusions: Associating an IABP with peripheral VA-ECMO was independently associated with a lower frequency of hydrostatic pulmonary oedema and more days off mechanical ventilation under ECMO.