An IABP is useful because, unlike any pharmacologic intervention, it is capable of increasing mean arterial pressure during diastole, which is critical for coronary perfusion, while lowering afterload to systolic LV ejection. IABP counterpulsation can mitigate post-bypass myocardial dysfunction by reducing afterload and augmenting diastolic (eg, coronary perfusion) pressures. Although IABPs have not demonstrated a survival benefit in patients with cardiogenic shock due to acute myocardial infarction, data suggest that some subsets of cardiac surgical patients benefit from prophylactic device placement. By contrast, in observational studies, intraoperative and postoperative IABP placement has been associated with worse postoperative outcomes, likely due to underlying shock pathology. The IABP only directly improves cardiac output by about 0.5 L/min, although if cardiac function is improved by enhanced perfusion and reduced afterload, then the cardiac output can be substantially increased. The IABP can only aid patients in whom ventricular function can recover in a relatively short time. Percutaneous VADs or extracorporeal membrane oxygenation (ECMO) might be more appropriate for patients who will require longer-term support.

References

• Heringlake M, Berggreen AE, Paarmann H. Still a place for aortic counterpulsation in cardiac surgery and patients with cardiogenic shock? Crit Care. 2021;25:309.
• Monaco F, Di Prima AL, Kim JH, et al. Management of challenging cardiopulmonary bypass separation. J Cardiothorac Vasc Anesth. 2020;34:1622-1635.
• Rocha Ferreira GS, de Almeida JP, Landoni G, et al. Effect of a perioperative intra-aortic balloon pump in high-risk cardiac surgery patients: a randomized clinical trial. Crit Care Med. 2018;46:e742-e750.