Tutorial 4: Pre-eclampsia

Question 1

What is gestational hypertensation?

Answer 1

new onset of hypertension > 20 weeks gestation with no features of preeclampsia , this is a new onset hypertension occurring in pregnancy

Question 2

What is chronic hypertension?

Answer 2

hypertension that was present prior to pregnancy or occurs <20 weeks gestation

Question 3

What is pre-eclampsia?

Answer 3

is a multi-system progressive disorder occurring after 20 weeks gestation , it is the presence of hypertension (defined as a BP of ≥140 mmHg systolic and/or ≥90 mmHg diastolic, based on at least 2 measurements taken at least 4 hours apart) \ with signs of other organ involvement.

Question 4

What are some differentials for pre-eclampsia?

Answer 4

Chronic hypertension

gestational hypertension

epilepsy

antiphospholipid syndrome

phaeochromocytoma

renal disease/ renovascular disease

liver disease

Question 5

What organs can be effected in pre-eclampsia?

Answer 5

1. Renal (most common)
2. Haematological
3. Liver
4. Neurological
5. Lungs
6. Vessels

Question 6

What are signs of renal involvement in pre-eclampsia?

Answer 6

1. Significant proteinuria – dipstick +1 , confirmed by spot urine protein/creatinine ratio ≥ 30mg/mmol or >300mg/24hr urine collection or plasma creatinine > 90 μmol/L
2. Oliguria

Question 7

What are signs of haematological involvement in pre-eclampsia?

Answer 7

1. Thrombocytopenia
2. Haemolysis
3. Disseminated intravascular coagulation (DIC)

Question 8

What are signs of liver involvment in pre-eclampsia?

Answer 8

1. Raised serum transaminases
2. Severe epigastric or right upper quadrant pain

Question 9

What are signs of neurological involvement in pre-eclampsia?

Answer 9

1. Convulsions (eclampsia)
2. Hypereflexia with sustained clonus
3. Severe headache
4. Persistent visual disturbances
5. Stroke

Question 10

What are signs of vascular involvement in pre-eclampsia?

Answer 10

1. Pulmonary oedema
2. Fetal growth restriction
3. Placental abruption

Question 11

What is severe hypertension?

Answer 11

is a SBP ≥ 170 and or DBP ≥110 mmHg on one occasion at any time.

Question 12

What are some risk factors for pre-eclampsia?

Answer 12

Nulliparity

Obesity

Previous Preeclampsia, family history

Diabetes

Renal disease

Multiple pregnancy

Autoimmune disease- e.g. antiphospholipid

Chronic hypertension

Recurrent miscarriage

Not Smoking

post IVF/different partner

Question 13

What are some clinical features of pre-eclampsia?

Answer 13

Occurring >20 weeks gestation

1. Hypertension (defined as BP ≥140 mmHg systolic and/or ≥90 mmHg diastolic) in a previously normotensive women, at least 2 measurements should be made, at least 4 hours apart.
2. Renal: dysuria, increased frequency, blood, tummy pain
3. Haematological: spontaneious bruising in absnece of trauama. Any bleeding (PV)
4. Liver: Epigastric pain, not fixed by medications (e.g. antacids). Right upper quadrant pain occurs in around 16% of cases of severe disease, a clinical symptom of HELLP syndrome.
5. Neurological: Frontal headache occurs in around 40% of patients. Increased irritability, nausea, blurred vision (Increased ICP) (recent change, do you have migraines)
6. Vessels: peripheral oedema (any recent/sudden increase in swelling or weight on legs, hands or face). SOB, dypnoea, fatigue.
7. Baby: Reduced fetal movements (how have baby’s movements been recently, relative to their normal pattern?). Reduced fetal growth occurs in around 30% (has the midwife said that the baby is smaller than she expects, or is he/she tracking well?)

Question 14

What prevents pre-eclampsia from occuring in normal pregnancies?

Answer 14

In normal pregnancy: the spiral arteries of the placenta invade deeply enough into the uterus, so that they dont constrict in reponse to vasoactive substances. This protects/ensures constant, adequate placental blood flow. (this vasoconstriction contributes to the hypertension/increased BP seen in pre-eclampsia)

Question 15

What is the pathophysiology of pre-eclampsia?

Answer 15

• Pre-eclampsia is thought to be caused by the failure of the normal invasion of trophoblast cells leading to a maladaption of the maternal spiral arterioles, these maternal arterioles are the source of blood supply to the fetus thus a maladaption in these arterioles leads to:
  
  • abnormal villous development and a subsequent
  • placental insufficiency thus hindering fetal growth.
• In pre-eclampsia there are fewer maternal spiral arteries that undergo the normal physiological dilatational change and a failure for these dilatational changes to extend into the myometrial segments, means that :
  
  • the lumen of these vessels may be occluded by fibrinoid material and lipid filled cells causing:
    
    • decreased placental perfusion
    • fetal growth restriction and
    • an increased risk of placental abruption

Question 16

What is pre-eclampsia thought to be due to?

Answer 16

The abnormalities of spiral artery adaptation are thought to be as a result of immunological and genetic influences.

However not all women with these factors develop pre-eclampsia thus a maternal response (to pregnancy) must be the decisive factor in development of systemic disease.

Question 17

What causes the hypertension and proteinuria seen in pre-eclampsia?

Answer 17

Hypertension and proteinuria are due to the vascular inflammatory response that produces vasoconstriction and capillary leakage.

This is believed to be as a result of placental ischaemia resulting in systemic endothelial cell dysfunction.

Question 18

What investigations would you want to include for pre-eclampsia?

Answer 18

1. Repeat blood pressure: at least 4 hours w. correct technique
2. Blood Tests:
   
   1. FBC, platelets –>blood film and coagulation profile (if abnormal)
   2. LFTs: albumin, AST, ALT (NB: Normal range in pregnancy are lower than for non-pregnant)
   3. Group and Hold
3. Urine tests:
   
   1. MSU
   2. Dipstick screening/PCR (protein creatinine ratio)
   3. 24hr collection >0.3g/24hr
4. Fetal wellbeing
   
   1. Ultrasound: fetal measurements+ amniotic fluid assessment
   2. CTG cardiotocography
   3. Umbilical artery doppler

Question 19

What are the indications of admissions re pre-eclampsia?

Answer 19

1. Neurological sx: Headaches, visual disturbance
2. Epigastric pain particularly in the right upper quadrant
3. Proteinuria ≥ 1+ AND hypertension SBP ≥ 160 and or DBP > 100
4. Abnormal blood tests: low platelets < 150, rising urate, raised creatinine (abnormal if > 80μmol/L), raised ALT, AST (abnormal if > 40iu) or raised bilirubin
5. APH Antepartum haemorrhage
6. Reduced fetal movements
7. Uterine activity

Question 20

What are the components of inpatient maternal monitoring for pre-eclampsia?

Answer 20

1. 4-6hrly BP:
   
   1. except overnight, 6hrly acceptable provided BP <160/100 on retiring
2. Daily urinanalysis
3. MSU (atleast 1)
4. 2x weekly:
   
   1. FBC (incl. Hb & platelet)
   2. creatinine, ruic acid, LFTs (albumin, ALT and AST)
5. Coagulation studies: if falling platelets (<100), abnormals LFTS or concern about placentla abruption
   
   1. Nb: lab investigations should be repeated more frequently if there are concerns about maternal or fetal condition

Question 21

What is the definitive treatment for pre-eclampsia?

Answer 21

Delivery of the placenta

Question 22

What is the treatment for pre-eclampsia?

Answer 22

Pre-eclampsia tx is dependant on gestational age:

1. Less than <32 weeks’ gestation: prolonging the pregnancy is beneficial for the fetus, as long as maternal and fetal assessments are stable.
   
   1. Antihypertensive therapy can be used.
   2. Corticosteroids are recommended before 34 weeks’ gestation to mature fetal lungs.
   3. Caesarean section is preferred.
2. 32 to 36 weeks’ gestation: there is little evidence to guide management, and decisions should be individualised.
   
   1. <34 weeks: Antenatal corticosteroids recommended. Unclear benefit for corticosteroids after 34 weeks.
   2. Method of delivery is made on an individual basis
3. >36 weeks’ gestation: Vaginal delivery is the most sensible approach.

Question 23

What is the treatment if a mother is <32weeks gestation with pre-eclampsia?

Answer 23

Less than <32 weeks’ gestation: prolonging the pregnancy is beneficial for the fetus, as long as maternal and fetal assessments are stable.

• Antihypertensive therapy can be used.
• Corticosteroids are recommended before 34 weeks’ gestation to mature fetal lungs.
• Caesarean section is preferred.
• 32 to 36 weeks’ gestation: there is little evidence to guide management, and decisions should be individualised.

Question 24

What is the treatment if a mother is 32-36 weeks gestation and has preeclampsia?

Answer 24

32 to 36 weeks’ gestation: there is little evidence to guide management, and decisions should be individualised.

• <34 weeks: Antenatal corticosteroids recommended. Unclear benefit for corticosteroids after 34 weeks.
• Method of delivery is made on an individual basis

Question 25

What is the treatment if a mother is >36 weeks gestation and has pre-eclampsia?

Answer 25

>36 weeks’ gestation: Vaginal delivery is the most sensible approach.

Question 26

What supplements/vitamins should be given to woman with pre-eclampsia?- esp. as preventative measures during subsequent pregnancies?

Answer 26

1. Low dose aspirin i.e 100mg daily early in pregnancy
   
   • can reduce the risk of preeclampsia by around 15%.
2. Calcium supplements:
   
   • esp if women has a low calcium intake
   • reduces the risk of preeclampsia by about 60%
3. Low dose multivitamin/folic acid
   
   • may help reduce preeclampsia occurance

Question 27

Which antihypertensives can be used during pregnancy for pre-eclampsia?

Answer 27

Anti-hypertensive drugs should be considered when the BP is consistently above SBP ≥ 140 - 160 and or DBP ≥ 95 - 100 consistently

• Methyldopa: start at 250mg tds, increasing to a maximum of 3g daily
• Labetalol: with food. Start 100mg bd increasing to 200 - 400mgs bd;
• Nifedipine slow-release: start 20mg SR bd; or 30 - 60mg nifedipine long-acting once a day
• Metoprolol: start 47.5mg CR bd, increasing to 95mg CR bd

Question 28

What are the specific indications for particular antihypertensives?

Answer 28

• Sudden onset of high blood pressure >/= 170/110:
  
  • use of short acting Nifedipine or iv labetalol
• Blood pressure greater than or equal to 160/100:
  
  • use methyldopa or labetalol
• Eclampsia: Magnesium sulphate

Control of hypertension and seizures needs to be continued after delivery until recovery is apparent. During this period, the main risk to the mother is fluid overload

Question 29

What measures need to be continued for a mother with pre-eclampsia following birth?

Answer 29

Control of hypertension and seizures needs to be continued after delivery until recovery is apparent.

During this period, the main risk to the mother is fluid overload

Question 30

What are the definitions/requirements for severe pre-eclampsia?

Answer 30

• Persistent, severe hypertension (SBP >170 or DBP >110)
• Oliguria:
  
  • <100/4 hours
  • <500ml/24 hours
• Serum creatinine >0.90 umol/L
• Neurological sx:
• Pulmonary oedema
• Liver dysfunction
• Haematological involvement (thrombocytopenia <100 or rapidky faling platelets, DIC)

Question 31

What is HELLP syndrome?

Answer 31

Haemolysis , Elevated liver functions, low platelets

• A serious condition that is considered a variant or complication off preeclampsia

Presentation:

• Mild: abdominal pain, nausea, vomiting, malaise, headaches, oedema , visual disturbances

The diagnosis of HELLP syndrome should be considered in any pregnant patient with new-onset epigastric/upper abdominal pain until proven otherwise

HELLP Diagnostic Criteria:

• Elevated liver transaminases (AST, ALT) >70 IU/L, total serum
• Lactate dehydrogenase (LDH) should be >600 IU/L
• platelet count should be <100 x 10^9/L <100,000/microL).
• Haemolysis may be indicated by:
  
  • elevated total bilirubin (>1.2 mg/dL [>20.5 micromol/L]),
  • LDH and AST elevations,
  • characteristic findings (schistocytes) on a peripheral blood smear,
  • haematuria
  • worsening anaemia
  • low serum haptoglobin

The only effective treatment is prompt delivery of the baby

Question 32

When should HELLP syndrome always be on your differential?

Answer 32

Pregnant lady, with new-onset epigastric/upper abdominal pain

= HELLP until proven otherwise

Question 33

What is the best treatment for HELLP syndrome?

Answer 33

the only effective treatment for HELLP is prompt delivery of the baby

Question 34

What are the key points to remember regarding pre-eclampsia?

Answer 34

• Pre-eclampsia is a multisystem disease, thus each organ system requires thorough ix and examination
• symptoms such as severe headache, visual disturbance, epigastric pain need to be inquired about
• hypertension in pregnancy can be treated however treatment of hypertension does not slow the preeclampsia disease progression only delivery of the palcenta will
• The Labour & Birthing registrar on call must be informed if any woman has SBP ≥ 170 and or DBP ≥ 110 which has failed to drop after 20 minutes
• 40% of eclamptic seizures occur after delivery

Question 35

What are three concerning symptoms in a pregnant woman?

Answer 35

• severe headache
• visual disturbance
• epigastric pain

Question 36

Does anything slow the progression of pre-eclampsia?

Answer 36

• Only delivery of the placenta slows the progression of pre-eclampsia as a disease (i.e. it is the only definitive treatment)
• Antihypertensives are symptomatic relief/compromise until delivery is safe and appropriate

Question 37

When must a registrar be made aware of a hypertensive woman?

Answer 37

Labour and Birthing on call reg must be informed if a woman has:

SBP >170 and/or

DBP >110

which has failed to drop after 20minutes

Question 38

When do most eclamptic seizures occur?

Answer 38

40% of eclamptic seizures occur after delivery

• what we are trying to avoid