Haemolytic Disease of the New Born Flashcards
What does rhesus refer to?
Various types of rhesus antigens on the surface of red blood cells.
What are rhesus antigens separate from?
The ABO blood groups
What is the most relevant antigen within the rhesus blood group system?
Rhesus-D antigen.
What does someone’s rhesus status in relation to pregnancy refer to?
Whether they have the rhesus-D antigen present on their red blood cell surface
Does a women who is rhesus positive require additional treatment when pregnant?
No
What happens when a woman that is rhesus-D negative becomes pregnant, with a rhesus positive baby?
The mother becomes sensitised to the rhesus D antigens
How does the mother become sensitised to the rhesus D antigen?
- The blood from the baby will find a way into the mother’s bloodstream.
- The baby’s red blood cells display the rhesus-D antigen.
What will the mothers immune system produce?
Antibodies to the rhesus-D antigen
anti-D antibodies
Does the sensitisation cause problems in the pregnancy?
Not in the first pregnancy but it will cause problems in subsequent pregnancies
What can occur in subsequent pregnancies?
The mother’s anti-rhesus-D antibodies can cross the placenta into the fetus
What will happen if the mother anti-D antibodies cross the placenta?
Antibodies attach themselves to the red blood cells of the fetus
This results in the destruction of the red blood cells (haemolysis).
What is the red cell destruction called?
Haemolytic disease of the new born.
What is the management of haemolytic disease of the new born?
Intramuscular anti-D injections to rhesus-D negative women.
Is there any way to reverse the sensitisation?
No- prophylaxis is really important
When are the anti-D injections given?
- 72 hours after the sensitisation has occurred
- 28 weeks gestation
- Birth (if the baby’s blood group is found to be rhesus-positive)
