**5.6 Miscellaneous concerns 5.6.1 Neurological outcome**

There is growing concern about their quality of life and neurocognitive function, as the long term survival of these children is now possible. 20 -50% may develop neurological impairment due to chronic hypoxaemia, prolong deep hypothermic circulatory arrest and prolong exposure to anaesthetics. Non pulsatile low flow during cardiopulmonary bypass causing ischaemia/reperfusion injury may also play a part19.

Brain adapts to chronic hypoxia due to presence of NMDA 2B receptors in early life. Cortical neurons may reduce by 30% due to chronic hypoxia causing reduction in brain volume. But this reduction is compensated when normoxia develops after surgery. Although most of the article have supported the use of high dose narcotics in over all outcome but at present there is no concrete evidence about best anaesthetic agents for congenital heart surgery.

### **5.6.2 Coagulation disturbances**

Coagulation abnormalities are very common in CHD patients particularly in cyanosed and polycythaemic patient.

Coagulation derangement associated with polycythaemia includes:


Use of blood products is common in paediatric cardiac surgery due to coagulopathy during surgery and several strategies have been instituted to minimize this practice. Preoperative exchange transfusion of 20 ml/kg FFP to replace same amount of blood is an effective method to counter coagulopathy. Antifibrinolytics like aprotinin and tranexamic acid20 have been used for this purpose. Aprotinin is no longer recommended in cardiac surgery due to higher incidence of renal failure, stroke and myocardial infarction while the use of tranexamic acid has increased.

Tranexamic acid as a part of blood saving strategy is given as a bolus of 100mg/kg followed by 10 mg/kg/hr infusion. Whole blood transfusion is quite effective in coagulopathic patients. Factor VII in the dose of 90 microgram/kg is increasingly used in paediatric congenital heart surgeries.
