The disappearance of foetal haemoglobin in congenital cyanotic heart disease.

Children with congenital cyanotic heart disease become adapted to some extent to anoxaemia. A well-recognized response is an increase of haemoglobin concentration; this increase might also be accompanied by a change in the type of haemoglobin formed. Foetal haemoglobin is more favourable than adult haemoglobin for oxygen uptake, and postnatal anoxaemia might promote the production of foetal haemoglobin in significant amounts. The observations reported here were made to test this hypothesis. Adams (1952) found that in a group of 19 infants and children with congenital cyanotic heart disease foetal haemoglobin did not persist in greater amounts than in a group of normal children and adults. The range of age of the cyanosed group was wide and included infants, children, adolescents and an adult aged 30 years, but their control group did not include any infants, the youngest patient being 4 years old, and the oldest 70 years. Their mean values in the cyanosed and control groups (6o% and 3 %) exceeded the accepted upper limits of 1 % to 2% in normal children and adults (Singer, Chernoff and Singer, 1951; Zannos, 1953; Huisman, Jonxis and Dozy, 1955; Jonxis and Visser, 1956). We used the optical method of Brinkman and Jonxis (1935), with modifications (White, 1956), to estimate the proportion of foetal haemoglobin from 24 full term normal infants. We found this to be a mean value of 720% with a range of 59% to 880%; this closely agrees with figures given by Schulman, Smith and Stern (1954) and Walker and Turnbull (1955). No foetal haemoglobin was demonstrated in the blood of four normal adults. The same method was then used to determine the proportion of foetal haemoglobin present in 25 infants and children aged from 6 weeks to 8 years with Fallot's tetralogy; the cyanosis in most of these patients was severe. During the same period 22 infants and children formed a control group. Method