A haematology SHO contacts you regarding a patient with congenital cyanotic heart disease. The patient has trisomy 2 and an unrepaired complete AVSD with Eisenmenger physiology and chronic cyanosis. The patient was seen recently in clinic and was doing reasonably well. The full blood count has been highlighted to the haematology team as the patient has a haemoglobin (Hb) of 27. The haematology records document a previous venesection when the Hb was around the same figure and the patient had developed headaches thought to be due to hyperviscosity. The SHO would like some advice on whether they should arrange for daycase venesection to reduce the risk of hyperviscosity complications and symptoms.
What advice should you give?A) As the patient is asymptomatic there is no indication for venesection
Polycythaemia is a physiological adaptive process to chronic cyanosis. Venesection should be avoided unless there are clear hyperviscosity symptoms. Venesection is not associated with a reduced risk of stroke and may cause iron deficiency and circulatory collapse without careful volume replacement.