Pulmonary Endarterectomy Under Deep Hypothermia

PEA was performed from median sternotomy, the patient was cooled to 18°C to 20°C using cardiopulmonary bypass (CBP), and bilateral PEA was performed under deep hypothermic circulatory arrest. Unfractionated heparin (Leo Pharmaceutical Products, Denmark) was used for intraoperative anticoagulation monitored by activated clotting time (ACT) (target > 480 s Kaolin-ACT, Medtronic.Inc. ACTII, Minneapolis, MN, USA). Before the initiation of CBP, 500 to 1000 ml of blood was harvested, and returned to the patient after weaning off CPB, heparin reversal by protamine sulfate, and decannulation. During CPB to maintain patients’ volume status and to minimize the use of crystalloids (plasmalyte 50 mg/ml, Baxter) and possible volume overload autologous blood transfusion (cell saver), allogenic red blood cell (RBC) transfusions (Hb < 60 g/l), 2 to 6 units of solvent-detergent treated standardized plasma (Octaplas®, Octapharma AG, Lachen, Switzerland) or albumin 20% were used. Tranexamic acid was used 30 mg/kg intravenously before the surgical incision and again 15 mg/kg every 2 h for the duration of CPB. ACT was controlled every 20 min on CPB and 3 min after each heparin bolus. After CPB, administration of protamine and harvested blood infusion, coagulation status was controlled (heparinase-ACT, complete blood count, APTT, PT, fibrinogen, AT and D-dimer). Postoperatively in the operation room allogenic RBC were transfused if Hb < 90 g/l or Hct < 30%. The threshold for platelet transfusion was the platelet count <100 ×10⁹/l and for standardized plasma, Octaplas®, PT < 30%.