Résumé
INTRODUCTION: Retrograde cerebral air embolism (CAE) is rarely described in literature that may be associated with manipulation of central or peripheral venous catheters. During a literature review, there were no described occurrences of CAE in patients on veno-venous (V-V) ECMO. DESCRIPTION: A 42-year-old male with ARDS secondary to COVID-19 pneumonitis was cannulated for V-V ECMO outside our facility and transferred to our cardiovascular intensive care unit. Upon arrival, he was noted to have a right femoral drainage cannula and right internal jugular (RIJ) venous antegrade cannula. On day 10 of his hospital stay he was converted to a RIJ Protek duo cannula and the right femoral drainage cannula was removed. This cannula was repositioned multiple times after placement due to flow issues. Due to poor oxygenator membrane function, it became necessary to exchange the oxygenator on day 25. During the exchange, the patient experienced sudden-onset bradycardia that progressed to several seconds of asystole. He regained spontaneous cardiac activity after a bolus dose of IV glycopyrrolate. Following this, he had several episodes of bradycardia and eventually asystole that resolved after one round of ACLS and IV atropine. The bradycardic episodes continued after this event and were associated with hypertension. On day 25, the patient suffered a decline in neurologic status from a GCS of 11T to 3T. The patient was sent emergently for non-contrast CT head. This scan revealed pneumocephalus with diffuse foci of air emboli in the subarachnoid and intraventricular spaces, the choroid plexus, and dural venous sinuses. After a family discussion, care was withdrawn from the patient on day 27. DISCUSSION: This patient suffered a massive retrograde CAE peri-ECMO circuit oxygenator exchange. It is our understanding that this a novel clinical situation for this phenomenon and not previously described in literature. This emphasizes that manipulation of any vascular cannula may result in the entrainment of air in a retrograde venous fashion into the cerebral vasculature.