Haemophilia Flashcards
What is the definition of haemophilia?
X- linked condition associated with reduction or absence of clotting factor: 8👉 haemophilia A
9👉 haemophilia B
🔴 bleeding into joints & muscles
How many neonatal males with severe haemophilia have no family history?
50 % of them
In these cases 👉 90% chance that the mother is a carrier.
When the woman is considered an “ obligate carrier “ for haemophilia?
- her father has haemophilia
OR - she has an affected son+affected relative in the maternal line.
When the woman is considered likely to be a carrier for haemophilia?
- she has an affected son
OR - she has a single carrier daughter
OR - she has an affected maternal relative
OR
*( F8/ vwf )<0.7 👉 suggestive of carriership. ( > 0.7 doesn’t exclude)
How is severity of haemophilia categorized?
According to the concentrations of F8/ F9:
Severe <0.01
Moderate 0.01- 0.05
Mild 0.06 - 0.4 iu/ ml
Why is it important to asses the severity of haemophilia?
❤Severe haemophilia 👉 require regular prophylaxis with clothing factor replacement
( they experience spontaneous bleeding into muscles & joints.
❤ moderate to mild: may only bleed following trauma or invasive procedures / require cover for these times.
What are the risks in pregnancy to a mother who is a carrier of haemophilia?
Risk of bleeding following:
Invasive procedures/termination/ miscarriage/ delivery.
🛑 F8/F9 levels should be checked prior to any procedure.
What are the risks in pregnancy to the baby of haemophilia carrier mother?
Male neonates with haemophilia:
⬆️ risk of bleeding: ICH & ECH ( extracranial haemorrhage)
⬆️ risk of iatrogenic bleeding.
What is the prepregnancy management for women who are carriers of haemophilia?
1- baseline factor level should be determined before pregnancy.
2- attention to weight
3- correction of any iron deficiency.
What are the options for prenatal diagnosis PND in carriers of severe haemophilia?
1- offer PGD
2- offer fetal sex determination by free fetal DNA from 9 w
3- carrier with male fetus 👉offer PND with chorionic villus sampling
At 11- 14 w
4- carrier with Male fetus 👉 offer 3rd trimester amniocentesis to determine haemophilia status ( to inform options for delivery)
When to check maternal F8/9 in pregnant women who are identified as carriers of haemophilia?
1- at booking
2- before any antenatal procedure
3- in the 3rd trimester.
What are the changes in F8/9 levels in pregnancy ?
F8 levels rise in pregnancy
F 9 tends to remain stable.
In pregnant women who are identified as carriers of haemophilia; what are the levels of F8/ 9 should be achieved before any procedure?
Aim for F8/9 levels of at least: 0.5 iu/ml
If treatment is required: 1 iu/ml & not allowed to fall below 0.5
What medications should be considered before procedures in pregnant women who are carriers of haemophilia?
❤ tranexamic acid: in combination with treatment if FLs< 0.5
Sole therapy if FLs > 0.5
❤ desmopressin DDAVP : to raise the F8 levels.
❤ recombinant F8 : if levels obtained by DDAVP are insufficient
Or known non responder
❤ recombinant F9 : in women with F9Ls < 0.5
What cautions should be considered in women who are treated by DDAVP?
1- fluids should be restricted to 1 L/ 24 h
2- monitor electrolytes. ( may cause hyponatremia ⬇️ Na)
3- should be avoided in women with preeclampsia.
When giving treatment to raise clotting factor levels; how to monitor the response?
By measuring FLs before & after infusion
4-6 hours following treatment to facilitate the dosing.
What is the optimal mode and timing of delivery, in carriers of haemophilia?
CS : in affected male babies
The fetal status is unknown
❤ AT 39 WEEKS
If vaginal delivery is intended: 👉 spontaneous labour is preferred
What to avoid during labour in fetuses at risk of haemophilia?
External cephalic version
Ventouse
Midcavity forceps
Fetal blood sampling
Fetal scalp electrodes
What is the effect of DDAVP on clotting factors ?
Can raise the levels of F8 + VWF
3 - 4 fold
What is the recommended dose of DDAVP before procedures in carriers of haemophilia?
0.3 mcg / kg ( IV or subcutaneous)
How can analgesia & anaesthesia be managed safely in carriers of haemophilia?
- FLs > 0.5 required for insertion or removal of epidural catheter or spinal anaesthesia.
🛑 if FLs < 0.5 👉 intramuscular injections should be avoided.
What is the haemostatic management during labour, in carriers of haemophilia?
🔴If FLs < 0.5 👉
*DDAVP : to raise F8 levels
*F9 concentrate : to raise F9
Aim for 1.0 iu / ml
🔴 FLs in low normal levels: tranexamic acid as sole therapy OR with previous medications.
🔴 should be given close to delivery as possible.
What is the postpartum management in carriers of haemophilia?
1- active management of 3rd stage.
2- maintain FLs > 0.5 for :
3 days after vaginal delivery
5 days after instrumental delivery
Or CS
3- tranexamic acid: until lochia is minimal
What is the neonatal management in babies for carriers of haemophilia?
All male babies 👉 cord sampling + diagnostic tests
Female babies 👉 testing not recommended
🛑 in a neonate with ⬇️ FL 👉 vit K orally
🔴severe or moderate haemophilia 👉 cranial US before discharge
🔴 symptoms or signs of ICH 👉 cranial MRI even if the Cranial US is normal.
