Pead Haemo Flashcards
where are the various haematopoiesis sites in the foetus
yolk sac - liver - spleen - bone marrow
why does foetal HbF have gamma chains
HbF has higher affinity for O2 so binds more strongly - take from mothers blood
which Hb chains do chromosome 16 and 11 code for
16 - zeta or alpha chains
11 - epsilon gamma or beta
in the first trimester what does the Hb start as and what can that turn into
Hb- gower- 1 = Hb zeta2/epsilon2
turns into Hb Portland (if the epsilon changes to gamma) or Hb-gower-2 (if the zeta changes to alpha)
what happens to Hb after the first trimester
changes from Hb portland (Hb zeta2/gamma2) and Hb-gower2 (Hb alpha2/epsilon2) to HbF resulting in both being (alpha2/gamma2)
what happens to Hb at the neonatal stage
Hb changes from HbF to HbA by switching the gamma to beta = Hb alpha2/beta2
what is the compensation of WBC in child vs adult
higher numbers of WBC in children but they are not as effective
what are the differences for platelets in adult vs child
adult numbers reached by 18th week gestation
large but then shrink at brith
functionally different but same effectiveness
ie baby hyper responsive to vWf but hypo to certain agonists
what assistance does the child immunity have
IgG cross placenta
IgA/D/E/M pass in breast milk
antibodies produced at 2-3 months
usually normal by 6 months
why are there bigger platelets made for compensation in the child
coagulation factors don’t cross placenta easily
which coagulation factors are present in normal amounts at birth
fibrinogen, factors V, VIII, XIII
which factors / protein are vit K dependant
II, VII, IX, X protein C/S
what is haemorrhage disease of the new born
immature liver makes insufficient vit K = lack of vit k dependent coagulation factors
why should you not use warfarin in children
teratogenic due to vit K depletion
what are examples of congenital childhood anaemias
haemoglobinophathy bone marrow failure syndromes bone marrow infiltration peripheral destruction blood loss
