MANAGEMENT OF MAJOR AIRWAY HAEMORRHAGE WITH VENOVENOUS EXTRACORPOREAL MEMBRANE OXYGENATION IN A HEART TRANSPLANT RECIPIENT

Abstract

<h3>Objective</h3> To report the successful use of venovenous extracorporeal membrane oxygenation in a heart transplant recipient with a catastrophic airway haemorrhage. <h3>Design and methods</h3> Review of hospital records and imaging. <h3>Results</h3> A 56 year-old man with a past medical history of asthma, bronchiectasis and immunoglobulin A deficiency presented with end-stage ischaemic cardiomyopathy and recurrent pulmonary oedema. He was assessed for and underwent a heart transplant. The donor graft was well matched, but a small soft left anterior descending coronary artery plaque was noted at retrieval. In the first 24 hours post-transplant, he had a falling cardiac index followed by dysrhythmias. He was placed on veno-arterial extracorporeal membrane oxygenation (VA ECMO) and underwent PCI to the LAD lesion and started on aspirin and prasugrel. 48 hours later, his oxygenation requirements increased, his chest x-ray showed infiltrates and differential hypoxia (Harlequin Syndrome) was diagnosed. VAV ECMO was established. Overnight following VAV ECMO, fresh blood and clots were suctioned from the endotracheal tube, with falling tidal volumes to the point he was effectively unventilated. A CT scan showed extensive bronchial casts. A rigid bronchoscopy removed the clot. No specific bleeding point was identified, but general ooze from both bronchi was observed. Antiplatelet agents and systemic heparin were stopped, whilst distal limb perfusion catheter heparin was continued. Serial bronchoscopies were performed daily, removing small quantities of clot and applying topical therapies to various bleeding points in the right upper lobe. Tidal volumes remained under 100ml. Disseminated intravascular coagulation was diagnosed and product replacement guided by laboratory results and thromboelastography was undertaken. With improving cardiac function, arterial decannulation was achieved, leaving the patient on VV ECMO. This was continued for a further week with repeated flexible bronchoscopy and clot retrieval. Bleeding resolved after several days with conservative therapy, avoiding surgical or interventional radiological procedures. Improvements in tidal volumes were observed and eventually VV ECMO was successfully weaned. Aspirin was restarted as single antiplatelet therapy. He subsequently made a good recovery. <h3>Discussion</h3> VV ECMO is well established as a treatment in respiratory failure and pulmonary haemorrhage. However, use of VAV and VV ECMO for a major airway bleed in a heart transplant patient has not, to our knowledge, been previously described. The risks of running circuits without anticoagulation in patients totally dependent on them are high and managing this risk, alongside the new stent in a crucial coronary artery, were challenging. This case highlights the importance of balancing thrombosis and bleeding risk, especially in the context of new coronary stents, and has prompted consideration whether short-acting agents such as tirofiban may have a role in these especially high-risk cases.