Shear-induced dysregulation of haemostasis during extracorporeal membrane oxygenation: From cells to circuit

Extracorporeal membrane oxygenation (ECMO) is increasingly being utilized in critical care globally to allow for adequate oxygenation in patients with cardiac and/or respiratory failure. Unfortunately, haemostatic complications - both thrombotic and haemorrhagic - are commonplace. Well established contributors to haemostatic dysfunction include patient-level characteristics, features of ECMO itself and the requirement of systemic anticoagulation to prevent circuit-related thrombosis. Research has focused on understanding how ECMO devices impact upon cellular components, particularly platelets, and plasma proteins involved in coagulation through assessment of phenotypic changes and activation profiles. A central feature of ECMO is the significant haemodynamic disturbances cells and circulating proteins experience within ECMO circuits. Given the body of evidence detailing the effects of haemodynamic shear on circulating cells critical for haemostasis, there is renewed focus on understanding the impact of shear on haemostatic dysfunction in ECMO. In this review, we describe the current landscape of ECMO-associated thrombosis and haemorrhage, provide insights into the impact of anticoagulation on haemostatic complications and highlight research evaluating the impact of shear on circulating cells and plasma proteins involved in haemostasis. Finally, we also discuss potential modifiers of haemostatic complications with a focus on development of personalized diagnostic and management approaches.