Dr.Hadil Magdi

1. Bleeding after Congenital Heart Surgery Dr.Hadil Magdi

2. Pathophysiology A bleeding diathesis has been recognized in pt. with CCHD, a variety of coagulation abnormalities has been postulated: 1-Polycythemia 2- Hyper viscosity. 3- DIC 4- Platelet function abnormalities. 5- Decreased production of coagulation factors. 6- Vitamin K deficiency. 7- Primary fibrinolysis.

3. Polycythemia Arterial hypoxia Erythropoietin RBC Blood viscosity Decompensated erythrocytosis.(as increased blood viscosity limiting factor in tissue oxygenation.)

4. Hyper viscosity (C/P) #Headache. #Fatigue. #Dizziness. #Visual disturbance. #Paresthesia. #myalgia. #Irritability.

5. Hyper viscosity Hyper viscosity symptoms occur usually at the level of packed cell volume much lower than that known to produce, it due to the associated iron deficiency anemia which is common in cyanotic infants (dietary).

6. Iron Deficiency Anemia+Polycythemia=Tissue perfusion(viscosity)

7. Thrombocytopenia Polycythemia Thrombocytopenia

8. DIC Polycythemia increased viscosity Decrease blood flow & tissue perfusion (Vascular stasis) Intravascular deposition of fibrin and platelet Consumption of platelet coagulation factors (DIC) Increase Risk of bleeding

9. Fibrinolysis Primary fibrinolysis due to coagulation abnormalities usually occur in cyanotic infants.

10. Impaired production of coagulation factor Laboratory Tests for hemotatic abnormalities PT, PTT are commonly longer in patients with haematocrit value >60%, However >50% of neonates had abnormal coagulation profile even in the absence of Polycythemia (Due to impaired synthesis and activation of factor II, vII, IX, X, because of Vit.K deficiency).

11. Other causes of bleeding in CCHD *Haemodilution resulting from high priming volume. *Delayed hepatic maturation secondary to poor organ perfusion. *Complex operative Procedures requiring long duration of CPB. *Multiple extracardiac lesions.

12. Preoperative preparation of the patient

13. Phlebotomy -Preoperative Phlebotomy was first suggested for CCHD Patients in 1964. -In older children (>5years old) 500 ml of blood over 30 to 45 min followed by an equivalent volume of isotonic saline, this may be followed every 24hrs by an additional 500ml phlebotomy until HB level of <65% is achieved.

14. Phlebotomy *Is recommended with symptomatic hyper- viscosity when dehydration is not the cause (Hb>65%). *The red blood cell reduction in CCHD improved platelet aggregation & lessen the risk of perioperative bleeding.

15. Phlebotomy RBC mass risk of cerebrovascular events (as a result of reduced CBF, secondary to hyper viscosity) therefore Phlebotomy reduce the risk of cerebral infarction.

16. NB: If Symptom of hyperviscosity does not improve after phlebotomy Possibility of concomitant iron deficiency anemia. (as iron deficient red blood cells are less deformable than normal RBC and does not pass through the microcirculation).

17. Strategies to decrease blood loss postoperatively A-Pharmacological approach: Aprotinin: Is a non specific serine protease inhibitors that inhibits fibrinolysis and complement activation due to its effect on the kallikrein/kinin system.

18. Disadvantage: 1-Expensive. 2-Thrombus formation. 3-severe hemodynamic instability. 4-Impaired renal function. 5-Risk of anaphylaxis(due to IgG, IgE antibodies).

19. Aminocaproic acid (EACA) is a synthetic agent that inhibit the fibrinolytic system by inhibiting activation of plasminogen (EACA) is used in a dose of 100mg /kg after anesthetic induction, 100mg /kg after in the CPB pump prime and 100mg / on weaning from CPB over 3 hrs.

20. Aminocaproic acid EACA has advantage over aprotinin : *Lower cost. *Less risk of anaphylactic.

21. Tranexanmic acid *Synthetic antifibrinolytic it act by effectively inhibiting fibrinolysis. *Is used in a single dose of 50mg/kg after skin incision.

22. B-Surgical technique modification Repeated median sternotomy technique it is a major challenge because it can be associated with ventricular or vascular surgery injury to overcome this problem precaution should be taken as: 1-Avoid sudden separation of sternum. 2-Avoid sharp dissection. 3-Elimination of electrocautary during lysis of adhesions. 4-Avilability of fresh blood. 5-Alternative approach to the femorofemoral bypass before sternotomy

23. C-CPB Modification (ultrafiltration during CPB) Ultrafiltration of the extracorporeal circuit volume after separation from CPB with reinfusion of thesalvage concentrate.

24. Advantage of ultrafiltration 1-Means of blood conservation. 2-Can attenuate the inflammatory response to CPB that lead to tissue edema and multiple organ dysfunction. 3-It lead to decrease interleukin I, interleukin 6, interleukin 8 and myloperoxidase this lead to decrease postoperative blood loss, time to extubation, postoperative alveolar arterial oxygen gradient.

25. Management of excessive bleeding after surgery Despite taking necessary precautions excessive bleeding can occur after surgery and treatment needs to be initiated after proper surgical hemostasis and adequate heparin neutralization have been achieved.

26. NB: Laboratory tests may be required to identify the haemostatic abnormality to guide proper therapy while waiting for the laboratory results, Fresh blood <48hrs should be transfused in children <2yrs old, in children >2yrs old platelet concentrate followed by FFP should be used and give better results than fresh whole blood.

27. Laboratory Results

31. Thank you