Complications-
Thrombotic complications were the most prevalent problem and were identified in 66% of the patients. Thrombotic complications were defined as excessive clotting during cannulation (clotted cannula despite pre-cannulation heparin bolus), early excessive fibrin formation in the oxygenator leading to a decreased post-oxygenator PaO2, repeated CRRT filter clot (in the presence of therapeutic anticoagulation), visible ECMO circuit thrombosis requiring emergent circuit change, pulmonary embolus (PE), type 2 HIT, and post ECMO deep venous thrombosis. Secondary infections occurred in seven of the fifteen patients and were treated effectively with broad spectrum antibiotics. The most common secondary infection was pneumonia. One patient developed a multidrug resistant Pseudomonas pneumonia infection after ECMO decannulation from ECMO. Two patients developed a pneumothorax after decannulation that required small bore chest tube placement.
Gastrointestinal (GI) bleeding requiring massive transfusion occurred in two patients. In one patient the GI bleed occurred after a tissue plasminogen activator (tPA) infusion while receiving a concurrent heparin infusion followed by a tPA/bivalirudin infusion. The tPA infusion was attempted to treat a presumed pulmonary micro-thrombosis in a patient with right ventricular (RV) failure after a PE that had caused a cardiac arrest. His cardiac arrest responded quickly to 50mg of tPA infusion and 1mg of epinephrine. The tPA infusion improved his RV failure minimally, but not significantly enough to avoid a period of VVA ECMO (14). This patient required VVA ECMO after an initial 21 days of VV ECMO. He was successfully decannulated after 5 days of VVA ECMO. In addition to the patient with the large PE, two other patients developed RV failure. One required VVAV ECMO cannulation, with drainage from the femoral vein and superior vena cava and return to the femoral artery and right atrium. The third patient with RV failure also required VAV support along with milrinone and an epinephrine infusion.