Hypertension in Pregnancy Flashcards
What % of primigravid women are affected by mild pre eclampsia?
10%
How does the plasma volume change in pregnancy?
increases 45%
How does the cardiac output change in pregnancy?
increases 30-50%
How does the stroke volume change in pregnancy?
increases 25%
How does the heart rate change in pregnancy?
increases 15-25%
How does the peripheral vascular resistance change in pregnancy?
decreases 15-20%
How is hypertension in pregnancy defined?
> /= 140/90 on 2 occasions OR
160/110 once OR
30/15 compared to first trimester reading
If a woman has hypertension in the first half of pregnancy, what is it likely to be?
undiagnosed hypertension
What are the risks of pregnancy for those with pre existing hypertension?
2x increase in PET
intrauterine growth restriction
abruption
What is pregnancy induced hypertension?
second half of pregnancy
resolved within 6 weeks of delivery
In PIH - what % progresses to pre eclampsia?
15%
What are the symptoms/signs of pre eclampsia?
hypertension
proteinuria (>/= 0.3g/l)
oedema
Can PET be asymptomatic?
YES
What is early PET?
<34 weeks
higher risk of maternal and foetal complications
What is late PET?
> 34 weeks
most common
more likely to lead to eclampsia and maternal death
What is seen in the placenta in early PET?
extensive villious and vascular lesions
What is seen in the placenta in late PET?
minimal placental lesions
How is the placenta affected in PET, and why?
abnormal placental perfusion leads to ischaemia -> endothelial dysfunction
endothelial activation leads to increased capiliary permeability, expression of CAM, prothrombic fators, platelet aggregation and vasoconstriction
What puts you at a higher risk of PET?
x3 risk if mother or sister had it
What is HELLP syndrome?
PET induced liver disease
What are the features of HELLP syndrome?
HELLP: haemolysis, elevated liver enzymes, low platelets
Epigastric/RUQ pain
high morbidity/mortality
What is PET induced placental disease?
fetal growth restriction
placental abruption
intrauterine death
What are the symptoms of hypertension?
headache visual disturbance epigastric/RUQ pain rapidly progressing oedema nausea/vomiting visual disturbance
What investigations should you do for a mother with hypertension?
U+Es, FBC, coagulation scree, LFTs, serum urate, protein creatinine ratio, CTG
USS foetus
How do you manage a mother with hypertension?
hypertension <20 weeks - look for secondary cause
treat hypertension
antenatal screening - BP, urine, MUAD (maternal uterine artery doppler) at 20-24 weeks
time the delivery
What are the risk factors that cause hypertension?
age >40 BMI >30 FH - 40% if sister, 25% if mother first pregnancy - 2-3x twins - 2x previous PE - 7x birth interval >10 yrs x2 molar pregnancy/triploidy pre existing renal disease/hypertension diabetes connective tissue diseases thrombophillia
What is the action of aspirin?
inhibits COX2 which prevents TXA2 synthesis
When should low dose aspirin be commenced?
before 16 weeks
How can LDA help PET?
causes a 15% reduction in it
If you have 2 of these moderate risk factors you should take LDA 75mg/day from 12weeks-> birth. What are they?
first pregnancy age >40 pregnancy interval >10years BMI >/= 35 FH of PET multiple pregnancy
If you have 1 of these high risk factors you should take LDA 75mg/day from 12 weeks-> birth. What are they?
hypertensive disease in previous pregnancy chronic kidney disease autoimmune disease T1DM or T2DM chronic hypertension
When should you admit someone to hospital with hypertension?
if BP >/= 170/110 OR
>/= 140/90 with ++ proteinuria
and significant symptoms/signs of foetal comprimise
What does MAP >/= 150 put you at risk of?
cerebral haemorrhage
What should a pregnant womans BP aims be?
140-150/90-100
What are 1st line antihypertensives used in pregnancy?
Methyl dopa - alpha agonist
Labetalol - alpha and beta agonist
Nifedipine - ca channel blocker
What are 2nd line antihypertensives used in pregnancy?
Hydralazine - vasodilator
Doxazocin - alpha antagonist
What antihypertensive drug is not safe for breastfeeding?
Doxazocin + Methyl dopa
When is Labetalol contraindicated?
asthma
When should you aim to deliver a baby after a PET diagnosis?
within 2 weeks
What is Eclampsia?
tonic clonic seizure occuring with features of PET - many have seizures before the onset of proteinuria/hypertension
When does eclampsia most commonly occur?
post partum - 44%
antepartum - 38%
Who is most likely to have eclampsia?
teenagers
How do you treat eclampsia?
control BP - IV labetalol or hydralazine
seizure treatment - magnesium sulfate IV 4g, if persistent diazepam 10mg IV
fluid balance
How should labour be managed in eclampsia?
aim for vaginal birth
epidural and control BP
avoid ergometrine
continous foetal monitoring
