Pre-eclampsia and eclampsia

Question 1

What is pre-existing hypertension?

Answer 1

Hypertension (BP>140/90) prior to 20wk GA, persisting >7wk postpartum.

Question 2

What are 4 complications of essential hypertension?

Answer 2

Increased risk of gestational HTN
Abruptio placentae
IUGR
IUFD

Question 3

What is gestational hypertension?

Answer 3

Development of hypertension (sBP >140 or dBP>90) after 20th wk GA in the absence of proteinuria in a woman known to be normotensive before pregnancy

Question 4

What are 5 maternal risk factors of gestational hypertension?

Answer 4

Primigravida (80-90% of gestational HTN)
Past history or family history of GA hypertension
DM, chronic HTN, or renal insufficiency
Obesity
Extremes of maternal age (<18 or >35 yr)

Question 5

What is pre-eclampsia

Answer 5

Preeclampsia is a disorder of widespread vascular endothelial malfunction and vasospasm that occurs after 20 weeks gestation and can present as late as 4-6 weeks post partum
It is clinically defined by hypertension and proteinuria, with or without pathologic edema.

Question 6

What quantity is hypertension

Answer 6

> 140/90 on 2 occasions in 6 hours

Question 7

What quantity is proteinuria

Answer 7

> 0.3g in a 24 urine sample
1+ or greater on dipstick
A protein to creatinine ratio of 0.3 or higher

Question 8

Why is a trace of proteinuria ignored on dipstick

Answer 8

This is almost always due to contamination by vaginal discharges or antiseptic solution

Question 9

What is pathological oedema

Answer 9

Oedema in the face, hands, abdominal wall, sacrum, vulva and lower limbs

Question 10

What are the requirements for diagnosing severe pre-eclampsia

Answer 10

BP > 160/110 on 2 occassions in 6 hrs
Proteinuria of at least 3g/5g in 24hr sample
3+/4+ on dipstick
Oliguria from renal failure
Cyanosis from pulmonary oedema
Symptoms of impending eclampsia (headache, visual disturbances or epigastric pain)
Features of HELLP syndrome

Question 11

What are 7 differential diagnosis for proteinuria in pregnancy?

Answer 11

1 - Pre-clampsia/eclampsia
2 - UTI
3 - Vaginal discharge, blood, mucus and meconium
4 - Renal disease eg glomerulonephritis or pyelonephritis
5 - Collagen vascular disease
6 - Sickle cell disease
7 - Orthostatic proteinuria in pregnancy

Question 13

What is the pathophysiology of pre-eclampsia in the kidney?

Answer 13

Glomerulo-capillary endotheliosis, endothelial cells swollen and blocks capillary lumen
↓ renal blood flow
↓ glomerular function
↓ in creatinine clearance
Results in proteinuria and in severe cases oliguria
Acute tubular necrosis and then acute renal failure

Question 14

What is the pathophysiology of pre-eclampsia in the brain?

Answer 14

Cerebrovascular haemorrhage, vasospasm* and oedema* -> increased neuronal activity -> convulsions
Headache, visual disturbances, nausea, vomitting and hyperreflexia are due to a central cause

Question 15

What is the pathophysiology of pre-eclampsia in the liver?

Answer 15

Have periportal haemorrhages and hepatocellular necrosis
URQ pain due to swelling of Glisson’s capsule
Elevated transaminases (above 10% normal) are a feature of HELLP syndrome

Question 16

What is the pathophysiology of pre-eclampsia on the cardio-respiratory systems?

Answer 16

Hypertension is a result of increased peripheral resistance from generalized vasospasm
Increased cardiac output may play a minor role
Cardiac failure and pulmonary oedema can occur so it is important to restrict IV fluids
Can also have adult respiratory distress syndrome

Question 17

What haematological changes occur in pre-eclampsia

Answer 17

↓ plasma volume = ↓ regional perfusion = hypovolemic shock if APH or PPH occurs
HCT rises and severity and duration of pre-eclampsia continues
Microangiopathic hemolytic anemia ⟶ altered thromboxane/prostacyclin ratio ⟶ fibrin deposition, coagulation factors and platelet consumption ⟶ mesh formation ⟶ RBC hemolysis and thrombocytopenia.

Question 18

What is the pathophysiology of pre-eclampsia in the uterus and placenta?

Answer 18

Uterus:
Uteroplacental perfusion ↓ by 55-60% 3-4wks before HTN ⟶ IUGR and perinatal mortality and morbidity
Placenta:
Possibility of placental abruption and DIC
Failure of trophoblast to invade spiral arteries of inner 1/3 of myometrium leading to acute atherosis (fibrinoid and foam cell deposition)

Question 19

What are predisposing factors for pre-eclampsia?

Answer 19

Nulliparity
Pre-clampsia in a previous pregnancy
FHx of pre-eclampsia
Extremes of age <18 or >40
Chronic renal disease
DM
Obesity

Question 20

What is Eclampsia?

Answer 20

New onset of tonic-clonic/grand mal seizure activity and/or unexplained coma in the setting of pre-eclampsia
and in the absence of other neurologic conditions

Question 20

Describe an eclampsia seizure

Answer 20

Tonic phase - may lose consciousness, facial twitching, eyes protrude, extremities flexed towards the body or extended away from it lasting 15 - 20 sec
Clonic phase - muscles contract and relax repeatedly lasting about 1 minute

Question 21

What is the aetiology of pre-eclampsia?

Answer 21

Genetic - 7% incresed risk in daughters, single recessive gene. 20 - 30% of daughter devlope it. 11-37% of sisters develop it
Immunological
Abnormalities in renin-angiotensin-aldosterone pathway
Altered prostacyclin-thromboxane ratio
Endothelial dysfunction

Question 22

What investigations do you do for pre-eclampsia

Answer 22

CBC - HB for MAHA and plt for thrombocytopenia
U&E - Cr for GFR, Uric acid gives fetal prognosis
LFT - elevated transaminases in HELLP syndrome
PT/PTT - thrombocytopenia, DIC, HELLP
MSU - to exclude differentials
24 urine sample - volume and proteinuria

Question 23

What is the goal of management in a pre-eclamptic patient?

Answer 23

To control BP and prevent any complications of the disease
Preventing seizure activity
Monitoring for systemic complications (maternal and fetal) of the disease
To deliver the fetus by the earliest and safest means
Delivery is the only cure

Question 24

What are 10 things initially done for management of mild pre-eclampsia?

Answer 24

1 - Admit for monitoring and investigations
2 - CBC, U&E, LFT, PT/PTT, GXM
3 - Ultrasound
4 - 24hr urine collection - creatinine and proteinuria
5 - CTG if >28wks
6 - Vitals and FHR ever 4 hrs
7 - Normal diet but avoid low salt diet
8 - Best rest
9 - DVT prophylaxis - heparin 5000u sc bd
10 - Corticosteroids if <34 wks - dexamethasone

Question 25

What medications are used for mild pre-eclampsia?

Answer 25

Aldomet (methyldopa) is 1st line, 250-500mg every 8-12 hrs

Slow release nifedipine 10mg every 12 hrs

Question 26

How do you manage pre-eclampsia one blood pressure and investigations are normal?

Answer 26

Patient managed as outpatient with daily fetal kick charting and weekly antenatal checks and advised to returned if;
1 - there are any symptoms of severe PE
2 - Any reduction in fetal movements
3 - Any abdominal pain or vaginal bleeding
4 - Spontaneous labour
Planned IOL at 38wks and continue antihypertensive in puerperium until weaned off

Question 27

What are the signs of severe pre-eclampsia?

Answer 27

Features of HELLP syndrome
Frontal headaches
Visual disturbances
Pulmonary oedema - cyanosis
RUQ/ epigastric pain/tenderness 
Haematuria/oliguria/anuria - renal failure
Hyperreflexia +/- clonus
IUGR 
Oligohydramnios

Question 28

What are 13 things initially done for management of severe pre-eclampsia?

Answer 28

1 - Admit for resuscitation, stabilization and investigations
2 - Lower BP < 155-105 with hydralazine or Labetolol
3 - CBC, U&E, LFT, PT/PTT, GXM
4 - Catheterize and monitor I/O every 1hr
5 - MgSO4
6 - CTG if >28wks
7 - Bedside ultrasound until stable and can go for full ultrasound
8 - 24 urine collection
9 - NPO until results come back then normal diet but NOT low salt diet
10 - Vitals every 1 - 2 hrs
11 - Bed rest
12 - DVT prophylaxis - heparin 5000u sc bd
13 - Corticosteroids - dexamethasone

Question 29

What are 8 indications for urgent delivery in severe pre-eclampsia

Answer 29

1 - Maternal BP cannot be controlled
2 - Thrombocytopenia and/or coagulopathy
3 - Hepatic impairment
4 - Renal impairment/failure 
5 - Symptomatic of pre-eclampsia 
6 - Imminent eclampsia / eclampsia 
7 - Fetal distress
8 - Lack of fetal growth over 10 - 14 days

Question 30

How do you manage severe pre-eclampsia after BP is controlled or delivery is warranted?

Answer 30

IOL is preferred unless C-section is indicated
MgSO4 continued for 24hrs post partum
Anti-hypertensive medication weaned off

Question 31

How do you manage eclampsia?

Answer 31

MgSO4 10g IM and 4g IV over 10-15mins then 5g IM every 4-6 hrs or 1-2g IV per hr for 24 hrs
MgSO4 - additional half dose if seizures continue
Diazepam - 10mg IV if seizures continue
Phenytoin - 10 - 15 mg/kg IV and NEVER more than 50mg/min
Manage same as severe pre-eclampsia and do urgent delivery
CT brain to rule out intracranial pathology as a cause or result