Computed tomography pulmonary angiogram in a poly-trauma patient undergoing veno venous extracorporeal membrane oxygenation: our experience in diagnosing pulmonary embolism

Abstract

Abstract Extracorporeal membrane oxygenation (ECMO) is an adapted form of the heart–lung machine that provides cardiopulmonary bypass life support for critically ill patients with acute cardiac and/or respiratory failure who are unresponsive to standard medical and surgical therapies. Although ECMO therapy has advanced significantly, complications like thrombosis and bleeding continue to be substantial, necessitating rapid transport of patients to the radiology suite to reveal crucial findings for further treatment plans or care. Even though the low flow rate for veno-arterial ECMO (VA-ECMO) support during contrast-enhanced CT is well known, the flow rate for veno-venous ECMO support during CT, especially computed tomography pulmonary angiography, is not well understood. Our case emphasizes that CTPA can be performed safely in trauma patients with ECMO runs and any suspected complications during ECMO runs may delay or worsen the clinical prognosis therefore immediate radiological verdicts may reveal significant findings to plan the treatment accordingly. Also, there were no complications associated with our examinations or transport. Our case highlights that VV-ECMO like VA-ECMO induces flow-dependent alterations in the patient’s circulation due to contrast injections, which might lead to an incorrect interpretation of CTPA. However, CTPA is safe, and bringing down the VV-ECMO flow rate of zero with vigilant monitoring of vitals and ventilation support helps radiologists to predict and interpret the contrast flow based on injection and cannula sites in the diagnosing and evaluation of pulmonary embolism patients with acute respiratory failure during ECMO.