Intra-aortic balloon pump impacts the regional haemodynamics of patients with cardiogenic shock treated with femoro-femoral veno-arterial extracorporeal membrane oxygenation

Abstract

Aims: To investigate the impact of intra-aortic balloon pump (IABP) on the regional haemodynamics of patients with severe cardiogenic shock undergoing femoro-femoral veno-arterial extracorporeal membrane oxygenation (VA-ECMO).

Methods and results: From July 2017 to April 2018, a total of 39 adult patients with cardiogenic shock receiving both IABP and ECMO for circulatory support were enrolled consecutively in a university-affiliated cardiac surgery intensive care unit. The blood flow rates (BFRs) of the bilateral femoral artery (IABP side: iFA, ECMO side: eFA) and carotid artery (left: LCA, right: RCA) and the velocity time integral (VTI) of aortic root were assessed by ultrasonography and compared when IABP was on and off. Seventeen of 39 (43.6%) patients survived to discharge, and 29 (74.4%) survived on ECMO. A total of 172 pairs of data (IABP on and off) were collected in this study, measured on the median of 2.0 (1.0, 4.5) days after patients received VA-ECMO. The BFR on both sides of FA (iFA: 176.4 ± 104.5 vs. 152.2 ± 139.8 mL/min, P < 0.01; eFA: 299.3 ± 279.9 vs. 242.4 ± 258.8 mL/min, P < 0.01) and the aortic VTI (10.1 ± 4.4 vs. 8.5 ± 4.4 cm, P < 0.01) decreased significantly when turning the IABP off, while the BFR on both sides of CA remained unchanged (LCA: 555.7 ± 326.9 vs. 578.6 ± 328.0 mL/min, P = 0.27; RCA: 550.0 ± 331.1 vs. 533.0 ± 303.5 mL/min, P = 0.30). The LCA BFR dramatically increased after turning the IABP off (296.8 ± 129.7 vs. 401.4 ± 278.1 mL/min, P = 0.02) in patients with cardiac stunning (defined as pulse pressure ≤ 5 mmHg). However, there was no significant difference in LCA BFR between IABP-On and IABD-Off (359.6 ± 105.4 mL/min vs. 389.6 ± 139.3 mL/min, P = 0.31) in patients with cardiac stunning receiving a higher ECMO blood flow (> 3.5 L/min).

Conclusions: Concomitant IABP used in patients undergoing femoro-femoral VA-ECMO was associated with increased aortic VTI and BFR in bilateral FA. The change in CA BFR depended on cardiac function. A decreased LCA BFR was observed in patients with cardiac stunning when IABP was turned on, which might be compensated by a higher ECMO blood flow. Further study is needed to confirm the relationship between BFR and extremities and neurological complications.

Keywords: Cardiogenic shock; Extracorporeal membrane oxygenation; Intra-aortic balloon pump; Regional haemodynamics.