Hypertension in Pregnancy Flashcards
(39 cards)
What percentage of pregnancies does hypertension usually affect?
10-15% of all pregnancies
How many primigravid (1st baby) mothers experience pre-eclampsia?
Mild pre-eclampsia = 10% primigravid women
Severe pre-eclampsia = 1% primigravid women
What is eclampsia?
seizure as a result of severe pre-eclampsia
- high risk of maternal death
When in pregnancy do changes in the cardiovascular system usually occur?
First 12 weeks
What cardiovascular changes does a mother experience in pregnancy?
- Increased plasma vol and CO
- Peripheral vascular resistance decreases
What trends in BP and heart rate are thought to occur in 2nd/3rd trimester of pregnancy?
- 2nd trimester = dip in BP (less marked than previously thought)
- 3rd trimester = increase in HR (around 7bpm)
What is the quantitative definition of hypertension?
≥140/90 mmHg on 2 occasions
>160/110 mmHg once
(some areas of world use increase of >30/15mmHg since 1st trimester)
What different types of hypertension can result during pregnancy?
- Pre-existing hypertension
- Pregnancy Induced Hypertension (PIH)
- Pre-eclampsia
What is the difference between Pregnancy Induced Hypertension (PIH) and Pre-eclampsia?
NO proteinuria or oedema in PIH
When is pre-existing hypertension most often diagnosed?
- 1st trimester => Likely if early pregnancy
- Retrospective diagnosis after pregnancy (if BP not returned to normal within 3 months of delivery)
What secondary causes may be responsible for pre-existing hypertension?
Renal / cardiac/ Endocrine
- Cushing’s
- Conn’s
- Phaeochromocytoma
What does pre-existing hypertension increase the risk of in pregnancy?
- PET
- IUGR
- Placental abruption
When does PIH normally present and resolve?
Second half of pregnancy
Resolves within 6/52 of delivery
What risks does pregnancy induced hypertension present?
- Progression to pre-eclampsia (15%)
- Rate of recurrence is high
What are the main features of pre-eclampsia?
Hypertension
Proteinuria (≥0.3g/l or ≥0.3g/24h)
Oedema
Pre-eclampsia can be “asymptomatic” on presentation. TRUE/FALSE?
TRUE
- patient may experience high BP, proteinuria and oedema but not feel unwell/ any abnormal symptoms
Describe the difference between early and late presentations of pre-eclampsia
Early
- extensive villous and vascular lesions of placenta
- higher risk of complications than late pre-eclampsia
Late
- minimal placental lesions
- relatively benign disease course but can lead to eclampsia
Describe the pathogenesis of pre-eclampsia
- Genetic (eg increased risk if mother/sister affected)
- environmental predisposition
- Stage 1 - abnormal placental perfusion
=> placental ischaemia/ infarction - Stage 2 - maternal syndrome
=> trophoblast invasion
=> failure of normal vascular remodelling
=> Spiral arteries fail to adapt to become high capacitance, low resistance vessels
=> Placental ischaemia
How does pre-eclampsia affect the liver to cause disease?
- Epigastric/ RUQ pain
- Abnormal liver enzymes
- Hepatic capsule rupture
- HELLP Syndrome
=> Haemolysis, Elevated Liver Enzymes, Low Platelets
What complications can pre-eclampsia cause which are specific to the placenta?
Fetal growth restriction (FGR)
Placental abruption
Intrauterine death
What symptoms normally present with pre-eclampsia?
- Headache
- Visual disturbance
- Epigastric / RUQ pain
- Nausea / vomiting
- Rapidly progressive oedema
Aside from the 3 common diagnostic signs, what other signs may be observed on examination of a mother with suspected pre-eclampsia?
- Abdominal tenderness
- Disorientation
- Small for Gestational Age (SGA) Fetus
- Intra uterine fetal death
- Hyper-reflexia / involuntary movements / clonus
(these signs develop prior to eclampsia seizure)
What investigations should be carried out throughout pregnancy if a mother has pre-eclampsia?
- Serum Urate
- LFTs
- FBC
- Coagulation Screen
- Cardiotocography
- US
What maternal risk factors can increase the likelihood or severity of pre-eclampsia?
Maternal Age BMI Family Hx Parity (first pregnancy) Multiple pregnancy (Twins/Triplets etc) Previous Pre-eclampsia Birth interval >10 years Molar Pregnancy / Triploidy
