Introduction
Veno-venous extracorporeal membrane oxygenation (ECMO) is now being applied to spontaneously breathing, awake patients when traditional, mechanical ventilation is not possible1. Current ECMO therapies provide a variety of options for the multidisciplinary teams involved in management5. Veno-venous ECMO can provide complete respiratory support, however, with substantial risks, including bleeding, thromboembolic events and infection5. Still, the advantage of veno-venous ECMO on awake patients minimizes the adverse effects of mechanical ventilation, including barotrauma, hypotension, and arrhythmias 2,4. It also minimizes the duration of neuromuscular blockade use that is usually used to improve patient ventilator dyssynchrony2,3. This method decreases the risk of critical care associated polyneuromyopathy and delirium as well2.
In the classic configuration, veno-venous ECMO support is achieved with two cannulae, one usually inserted in the right femoral vein and advanced to the junction between the inferior vena cava (IVC) and the right atrium (RA) and the other inserted in the right internal jugular vein (IJV) and advanced through the superior vena cava (SVC) into the RA5. This configuration was implemented in our patient procedure (Figure 1).
The decision was also made to not use anticoagulation during the procedure. With thromboembolic complications remaining the major causes of death in patients undergoing ECMO treatments, this decision was unique and a crucial component of our particular procedure6. With complications commencing upon blood contact with artificial surfaces of the circuit, blood pump, and oxygenator system, ECMO use naturally increases the risk of hemorrhagic and thromboembolic events6. Therefore, anticoagulation therapy, predominantly with unfractionated heparin, is almost always required in cases to prevent these problems6. Still, with a lack of high-quality data to guide anticoagulation management in ECMO patients, results in marked practice vary considerably among centers7. In our particular case, increased risk of bleeding and small area of operating site were taken into consideration, therefore leading to the decision to not use anticoagulation. Although highly effective at the prevention and treatment of thromboembolism, anticoagulants are by their very nature associated with significant bleeding risks8. Numerous individual clinical factors have been linked to an increased risk of hemorrhage, with our particular patient being susceptible, given her older age and history of renal disease8. More specific details of the patient and Otolaryngology procedure will follow.