The johnsons preeclampsia

Question 1

Name 2 causes of pre-eclampsia and describe its pathophysiology

Answer 1

Two causes include: (1) Increased resistance to blood flow in the uteroplacental circulation due to abnormal, superficial trophoblast implantation, leading to placental ischemia and hypoxia; and (2) maternal endothelial dysfunction, which triggers a systemic prothrombotic and hypertensive state.

The pathophysiology involves placental ischemia and hypoxia caused by defective uteroplacental blood flow. This is typically due to a failure of spiral artery remodeling during early gestation, resulting in persistently high-resistance vessels. In response, the placenta releases vasoconstrictors (e.g. thromboxane A2) and reduces vasodilators (e.g. nitric oxide and prostacyclin), increasing maternal systemic vascular resistance and causing hypertension.

Widespread maternal endothelial dysfunction also occurs due to the release of anti-angiogenic factors such as sFLT-1, which antagonize pro-angiogenic factors like VEGF and PIGF. This contributes to a prothrombotic state that may lead to disseminated intravascular coagulation (DIC), multiorgan ischemia, liver and kidney dysfunction, and CNS disturbances.

Question 2

Name 4 high risk and 4 moderate risk factors for preeclampsia

Answer 2

High
-Chronic hypertension
-Prev pre-eclampsia
-Kidney disease
-Diabetes
-Autoimmunity (esp SLE/ antiphospholipid syndrome)

Moderate
- Age > 40
- >10 year gap between pregnancies
- BMI > 35
- Multiple pregnancies
- First pregnancy

Question 3

Name 2 function of human placental lactogen (hPL)

Answer 3

hPL is produced by the placental syncytiotrophoblasts

Functions:
(1) Increases maternal insulin resistance: Raises maternal blood glucose to ensure a steady supply of glucose to the fetus.

(2) Stimulates lipolysis in the mother: Provides free fatty acids as an alternative energy source for the mother, conserving glucose for fetal use. It also allows for production of ketones that can also be used by the fetus for energy.