Pre-eclampsia

• What is a term delivery?

  Between 37 weeks to 41 + 6 weeks
• What is a pre-term delivery?

  Delivery before 37 weeks
• What are the different classifications of pre-term delivery?

  Moderate to late preterm -> 32 - 37 weeks

  Very preterm -> 28 to 32 weeks

  Extremely preterm -> less than 28 weeks
• Hypertensive disorders in pregnancy affect around 8 - 10% of preganancies.

  One of the leading causes of direct maternal deaths in UK.
• What are the feotal complications of hypertensive disorders in pregnancy?

  Intrauterine growth restriction

  Pre-term delivery

  Intrauterine death
• What are the different types of hypertension in pregnancy?


  Chronic hypertension

  Gestational hypertension

  Pre-eclampsia
• What is chronic hypertension?

  Hypertension either known prior to pregnancy, or picked up before 20 weeks gestation

  This is because in early pregnancy TPR falls & CO does not catch up until around 22 weeks -> so BP is usually lower before 20 weeks

  So, hypertension detected before 20 weeks gestation is NOT related to pregnancy
• What drugs should NOT be prescribed to manage HTN in pregnancy (chronic/gestational)?

  ARBs

  ACE inhibitors
• What drugs are usually first line to prescribe to manage chronic HTN in pregnancy (chronic/gestational)?

  Labetalol

  Nifedipine
• What is gestational HTN?

  New onset of hypertension after 20 weeks gestation, in the absence of symptoms
• What is pre-eclampsia?

  Hypertensive disroder in pregnancy

  Usually develops between 20 weeks gestation and 6 weeks post-partum

  Multi-system condition (can affect kidneys, liver, brain, eyes & other organs)
• What is the diagnostic criteria for pre-eclampsia?

  BP > 140/90 AND significant proteinuria
• What is severe pre-eclampsia?

  BP > 160/110
• What is significant proteinuria?

  Greater than or equal to 0.3g in a 24 houts urine specimen
• What are the risk factors of pre-eclampsia?

  First pregnancy

  BMI > 35

  CKD

  Previous pre-eclampsia/hypertensive disorder of pregnancy

  Maternal age > 40

  Pre-existing HTN

  Family history of pre-eclampsia

  Multiple pregnancy

  Antiphospholipid antibody syndrome

  Pregnancy interval > 10 years

  Diabetes

  Autoimmune disease
• What is given as prophylaxis for pts at risk of pre-eclampsia?

  Low dose aspirin from 12 weeks gestation

  Reduces risk of developing pre-eclampsia by 15%
• What is the pathophysiology of pre-eclampsia?

  Exact cause not fully understood.

  Abnormal development of placental vessels (spiral arteries) -> vessels are narrowed -> less blood flow through placenta
• What are the effects of pre-eclampsia on the foetus?

  Foetal growth restriction

  Maybe even foetal death
• What are the effects of pre-eclampsia on the mother?

  Hypoperfused placenta -> release of pro-inflammatory proteins -> endothelial cell dysfunction -> vasoconstriction & salt retention -> hypertension
• What are the features of pre-eclampsia?

  Glomerular damage

  • oligouria (less urine)
  • proteinuria

  Retina

  • blurred vision
  • flashing light
  • scotoma (focal blurry vision)

  Liver swelling

  • elevated liver enzymes
  • right epigastric pain
  • nausea & vomiting

  Vascular permeability

  • oedema in legs, hands, face
  • pulmonary oedema (SOB, cough)
  • cerebral oedema (headaches & seizures)
• What are the investigations for pre-eclampsia?

  Frequent BP monitoring

  Urine dipstick (albumin: creatinine ratio)

  Bloods (FBC, U&Es, LFTs & uric acid)

  Ultrasound (foetal gorwth & wellbeing, uterine artery blood flow)
• What are the immediate complications of pre-eclampsia ?

  Placental abruption

  HELLP Syndrome

  Eclampsia
• What is placental abruption?

  Placenta detached prematurely from uterine wall -> rapid foetal compromise
• What is HELLP Syndrome?

  Haemolysis - destruction of RBCs by turbulent blood flow caused by thrombi formation

  Elevated Liver enzymes - vasospasm of the vessels supplying the liver -> liver swelling

  Low Platelets -> endothelial injury causes tiny thrombi to form in blood vessels -> uses up platelets
• What is eclampsia?

  Pre-eclampsia + seizures = eclampsia

  New tonic-clonic seizures - due to cerebral oedema

  Majority of seizures occur in post-natal period
• What is the management of eclampsia?

  Obstetric emergency call

  IV magnesium sulphate for prevention & treatment

  IV antihypertensive (labetalol or hydralazine)

  Continous monitoring of mother & baby

  Prompt delivery of foetus (emergency C-section) once the mother is stable
• What can be used to predict pre-eclampsia?

  sFlt-1 to PlGF ratio

  Ratio between 2 placentally derived biomarkers

  Can be used to predict short term onset of pre-eclampsia in patients who are at high risk -> risk of developing pre-eclampsia in next 7 days
• What is the management of pre-eclampsia?

  Monitoring (patient education, frequent BP check, weekly bloods, serial growth scans)

  Location of care (home -> stable & mild, admission if BP unstable)

  Medication (antihypertensive, seizure prevention)

  Delivery (may need to deliver pre-term)
• What is the only definitive treatment of pre-eclampsia?

  Delivery of the placenta
• What are the delayed complications of pre-eclampsia?

  Increased risk of…

  • pre-eclampsia in another pregnancy
  • HTN
  • stroke
  • major adverse CV event