Efficacy of ECMO Circuit without Anticoagulation in Asian Population

1. ELSO-EURO Rome June 2012 Oral abstract presentation ECMO Circuit Efficacy and Complications in patients on ECMO Without systemic Anticoagulation : a Case series in Asian population Department of Intensive Care Unit Queen Mary Hospital The University of Hong Kong Sin WC , Ngai CW , Chan WM

2. Background (1) • The ELSO guideline suggested continuous infusion of heparin during ECLS despite the surface of some extracorporeal circuit and devices are heparin coated • However, bleeding in ECLS resulted in significant morbidity and mortality

3. Background (2) • Hong Kong Med Journal 2002 • JACC 2007 • Asian tends to bleed and Caucasian tends to clot • Lower incidence of deep vein thrombosis in Chinese • Absence of factor V gene mutation and prothrombin gene mutation in Chinese 1 • Higher incidence of intracranial bleeding after warfarinzation for atrial fibrillation in Asian • Differences in gene encoding vitamin K epoxide reductase complex • haplotypes predictive of low maintenance dose of warfarin in 89% of Asian but 35% in Caucasian 2 • Bleeding risk further increase in patients with underlying/ ongoing coagulopathy and platelet dysfunction

4. Objectives to review circuit efficacy, safety and patient outcomes in ECLS without systemic anticoagulation in Asian population

5. ECLS for cardiopulmonary support since Nov 2010 • 14 cases recruited • 6 without systemic anticoagulation • heparin coated circuit and membrane oxygenation (Cardiohelp HLS set advanced 7.0 Bioline coating oxygenator; MAQUET, Germany) • Percutaneous peripheral cannulation with seldinger technique

6. Protocol • Blood flow 50-80ml/kg/min • Gas flow 1:1 to blood flow • SpO2 95% (VA) , 85-92% (VV) • PaCO2 35-45mmHg • Pre-oxygenator oxygenation> 65% • Routine reperfusion catheter in superficial femoral artery • Lung rest ventilator strategy • MAP 65-95 mmHg • Conventional heparin for anticoagulation • ACT 170-200 sec • APTT 1.5-2.0 times of normal • Platelet > 100,000/mm3 • Hb~10 g/dl • pH 7.35-7.45

7. Six patients were considered to be at high risk of bleeding and systemic anticoagulation was not given • They included • 2 patients with ongoing bleeding • Haemorrhagic gastritis • Haemorrhagic cystitis • 4 patients with underlying severe thrombocytopenia ± coagulopathy

13. Empirical change of oxygenator No abnormality in TMPD and oxygenation function

15. Conclusion  Discussion • Early experience • Similar circuit efficacy • No excessive clinical complications • Trend toward higher mortality may be due to higher proportion of immunosuppressed patients • Platelet transfusion • Intrinsic defect in patients with hematological disease • Excessive platelet transfusion cause oxygenator failure • Packed cell transfusion • Similar vs. anticoagulation free group • Much lower vs. international reported data • ? Peripheral , seldinger cannulation

16. Advance in technology Bioline coating PVC uncoated

17. Multifactorial Red blood cell (Anaemia) Clot Clotting factors (Ethnic difference) Coagulopathy Anti-thrombotic agent Platelet (Thrombocytopenia) Quantity and function Antiplatelet agent

18. Reasonable to lower the target of anticoagulation in patients with high bleeding risk

19. Thank You

20. Thromboelastogram

22. Transfusion requirement

23. Ethnic difference DVT post op in HK , Taiwan and Singapore 2.6 , 7.7 and 4.7%

24. ESC guideline 2011

25. ESC guideline 2011