Hypertension in Pregnancy Flashcards
What is the commonest cause of iatrogenic prematurity?
pre-eclampsia
When do most of the CVS changes in pregnnacy occur?
first trimester
What is blood pressure proportional to?
systemic vascular resistance and cardiac output
What happens to BP in the first trimester?
falls
When does BP drop to its lowest in pregnnacy?
22-24 weeks
What is normal BP in early pregnancy?
90-100/50-60
When does BP return to normal post-partum?
6 weeks
What is hypertension in pregnnacy defined as?
> =140/90 on 2 occasions; >160/110 once
What are the 3 types of hypertension in pregnnacy?
pre-existing HT; pregnnacy induced HT; pre-eclampsia
What makes pre-existing HT likely diagnosis in pregnnacy?
if HT in early pregnnacy
When does PET and PIH tend to occur in pregnnacy?
second half f pregnnacy
What are the risks of pre-existing HT in pregnancy?
PET; IUGR and abruption
When does PIH resolve?
within 6/52 od delivery
What is the typical triad of symptoms seen with pre-eclampsia?
HT; proteinuria; oedema
What is proteinuria defined as?
> =0.3g/L or >=0.3g/24h
What is pre-eclampsia?
diffuse casvular endothelial dysfunction with widespread circulatory disturbance
What is early pre-eclampsia?
<34 weeks
What is late pre-eclampsia?
> =34 weeks
Is late or early pre-eclampsia more common?
late (almost 90%)
What features of placental dysfunction are found in early pre-eclampsia?
extensive villous and vascular lesions of the placenta
What is the difference between outcomes between early and late pre-eclampsia ?
early- higher risk of maternal and fetal complications but late has higher rates of eclampsia and maternal death
Which type of pre-eclampsia does maternal factors such as HT and metabolic syndrome play a greater role?
late pre-eclampsia
What is stage 1 of pre-eclampsia?
abnormal placental perfusion due to failure of trophoblastic invasion- placental ischaemia
What is stage 2 of pre-eclampsia?
maternal syndrome- an anti-angiogenic state assoc. with endothelial dysfunction leading to organ involvement
What causes the widespread endothelial dysfunction and damage in pre=eclampsia?
injured placenta releases toxins and high resistance of spiral artery causes maternal BP to rise to compensate
What happens when endothelial cells are activated in pre-eclampsia?
increased capillary permeability; expression of CAM; prothromotic factors; platelet aggregation and vasoconstriction
What do the cytotrophoblasts not do that causes the problems in pre-eclampsia?
do not invade the smooth muscle of the spiral artery so they still have high resistance
What are the effects of pre-eclampsia on the CNS?
eclampsia; hypertensive encephalopathyl intracranial haemorrhage; cerebral oedema; cortical blindness; CN palsy
What renal disease is seen with pre-eclampsia?
decreased GFR; proteinuria; increased serum uric acid; creat; K and urea; acute renal failure
What liver disease is seen with pre-eclampsia?
epigastric/RUQ pain; abnormal liver enzymes; hepatic capusle rutpure; HELLP syndrome
What is HELLP syndrome?
Haemolysis; elevated liver enzymes and low platelets
What haematological disease is seen in pre-eclampsia?
decreased plasma volume; thrombocytopenia; haemolysis; disseminated intravascular coagulation
What causes pulmonary oedema in pre-eclampsia?
iatrogenic- fluid overloaded
What can pulmonary oedema lead to?
ARDS
What placental disease is seen with pre-eclampsia?
IUGR; placental abruption; IUD
What are the symptoms of pre-eclampsia?
HA: visual disturbance; epigastric/ RUQ pain; N and V; rapidly prgressive oedema
What are the signs of pre-eclampsia?
HT; proteinuria; oedema; abdo tenderness; disorientation; SGA; IUD; hyper-reflexia/ involuntary movements/ clonus
What blood level is often the first thing to be elevated in pre-eclampsia?
serum urate
What investigations should be done for pre-eclampsia?
U&Es; serum urate; LFTs; FBC; coag screen; urine PCR; CTG and US
What shoudl be done if a woman has HT <20 weeks?
look for secondary causes
What are hte risk factors for developing pre-eclampsia?
> 40 yo; >30 BMI; FHx; nulliparity; multiple pregnnacy; previous PE; birth interval >10 years; molar pregnancy;
What are the medical risk factors for devleoping pre-eclampsia?
renal disease; HT; diabetes; connective tissue disease; thrombophilias
When should low dose aspirin be given for preventing PET?
high risk women- renal DM; APS; multiple risk factors prev PET
When should low dose aspirin as a preventative be started?
before 12 weeks
What measurement on USS is used to predict pre-eclampsia?
maternal uterine artery doppler
When is MUAD done?
20-24 weeks
When should a woman be admitted with hypertension?
BP >170/110 OR >140/90 with ++proteinuria; sgnif symptoms ; abnormal biochemistry; signif proteinurai; need for antihypertensive therapy; signs of fetal compromise
How often should BP done as an inpatient?
4hrly
How often should UA be done as an inpatient?
daily
What is there a great risk of if MAP >=150
cerebral haemorrhage
What is the MOA of methyldopa?
centrally acting alpha agonist
What is the CI for methyldopa?
depression
What is the MOA of labetolol?
alpha and beta antagnoist
What is the CI for labetolol?
asthma
What is the MOA of nifedipine?
Ca channel antagonist
What is the MOA of hydralazine?
vasdilator
What is the MOA of doxazocin?
alpha antagonist
When should doxazocin not be used?
in breast feeding
What is the only cure for pre-eclampsia?
birth
What are the indications for birth with pre-eclampsia?
term gestation; inability to control BP; rapidly deteriorating biochem; eclampsia; featl compromise
What are the crises in pre-eclampsia?
eclampsia; HELLP syndrome; po oedema; placental abruption; cerebral haemorrhage; cortical blindness; DIC; acute renal failures; hepatic rupture
What is eclampsia?
tonic-clonic seizure occuring with features of pre-eclampsia
Why is eclampsia difficult to prevent?
> 1/3rd will have seizure before onset of HT/proteinuria
What age group is eclampsia more common in?
teens
What drug is used as seizure tx/prophylaxis?
magnesium sulphate
What drug should be used with persistent seizures?
diazepam
Why should epidural anaesthesia be recommended in pre-eclampsia/ eclampsia?
hypotension and relaxes patient
What drug should be avoided during the 3rd atge with eclampsia?
ergometrin
