Hypertension Flashcards
What percentage of pregnancies are affected by hypertension?
10-15%
Define hypertension in pregnancy
> 140/90 on 2 occasions
160/110 once
30/15mmHg compared to first trimester BP
Name three types of hypertension in pregnancy
Pre-existing
Pregnancy induced
Pre-eclampsia
What are the secondary causes of hypertension in early pregnancy?
Renal Cardiac Cushing's Conn's Phaeochromocytoma
What are the risk of pre-existing hypertension?
PET
IUGR
Abruption
Describe pregnancy induced hypertension
Second half of pregnancy usually resolves within 6 weeks of delivery
What is the triad of pre-eclampsia?
Hypertension
Proteinuria
Oedema
Define pre-eclampsia
A pregnancy specific multi-system disorder with unpredictable variable and widespread manifestations
Describe the pathogenesis of pre-eclampsia
Genetic and environmental factors
Cause defective deep placentation, the injured placenta releases factors into the maternal circulation
State the two stages of pre-eclampsia
Stage 1 - abnormal placental perfusion (ischaemia)
Stage 2 - maternal syndrome
What does abnormal placentation and trophoblast invasion do?
Failure of vascular remodelling
What happens as a result of endothelial activation?
Increased capillary permeability
Increased expression of CAM
Increased prothrombotic factors, platelet aggregation and vasoconstriction
What does HELLP stand for?
Haemolysis Elevated Liver enzymes Low Platelets
How does HELLP syndrome present?
Epigastric/RUQ pain
Abnormal enzymes
Hepatic capsule rupture
What are the symptoms of pre-eclampsia?
Headache Visual disturbance Epigastric/RUQ pain Nausea, vomiting Rapidly progressive oedema
What are the signs of pre-eclampsia?
Hypertension Proteinuria Oedema Abdominal tenderness Small for gestational age Intra-uterine foetal death Involuntary movements/clonus
Name the investigations done in suspected pre-eclampsia
Urea and electrolytes Serum urate Liver function tests Full blood count Coagulation screen Urine-Protein Creatinine ration Cardiotocography Ultrasound
How often should bloods be done in women with pre-eclampsia?
2 weekly
How often should urinalysis be done in women with pre-eclampsia?
daily
How often should BP be measured in women with pre-eclampsia?
4 hourly
Name the risk factors for pre-eclampsia
Maternal age BMI Parity Previous PE Family History - hypertension, diabetes, APLS, autoimmune Multiple/molar pregnancy Birth interval >10 years UTI
What is the mode of action of aspirin?
Inhibits cycle-oxygenase to prevent TXA2 synthesis
What is classed as high risk and what dose of aspirin is required?
Hypertension, CKD, autoimmune disease, diabetes
150mg daily 12-36 weeks
What is classed as moderate risk and what dose of aspirin is required?
> 40 years old, BMI >35, family history, multiple pregnancy, first pregnancy, birth interval >10 years
When should a women be admitted?
BP >170/110 or >140/90+proteinuria Significant symptoms Abnormal biochemistry Significant proteinuria >300mg/24 hours Requires anti-hypertensives Signs of fetal compromise
At what MAP is there a risk of cerebral haemorrhage?
> 150
What is the BP aim?
140-150/90-100mmHg
What BP requires immediate treatment?
> 170/110
Name the first line for hypertension in pregnancy
Methyl dopa - alpha agonist
Labetolol - alpha and beta blocker
Nifedipine - CCB
Are there any contraindications for the first line hypertension treatment?
Methyl dopa - depression
Labetolol - asthma
Name the second line hypertension drugs
Hydralazine - vasodilator
Doxazocin - alpha agonist
What drug cannot be used while breast feeding?
Doxazocin
What is the only cure to pre-eclampsia?
Delivery
When is delivery indicated?
Inability to control BP Rapidly deteriorating Eclampsia crisis Fetal compromise Term gestation
What is a pre-eclampsic crisis?
Eclampsia HELLP Pulmonary oedema Placental abruption DIC Cerebral haemorrhage Cortical blindness Acute renal failure Hepatic rupture
What is eclampsia?
Tonic-clonic seizure with features of pre-eclampsia
Which age group is eclampsia more common?
Teenagers
What antihypertensives can be given in eclampsia?
IV labetolol
IV hydralazine
What is given in eclamptic seizures?
Magnesium sulphate
Diazepam if persistent
Usually self limiting and will settle
Describe the mechanism of action of magnesium suphate
Calcium channel blocker - improves foetal neurology in preterm labour
Name two steroids that cross the placenta
Betamethasone
Dexamethasone
How often do you given steroids in eclampsia and why?
IM corticosteroids 12-24 hours apart to help maturation of foetal lungs up to 34 weeks
What do steroids reduce risk of?
Neonatal death Intraventricular haemorrhage Necrotising enterocolitis NICU/ICU admission Systemic infection
