Pre-eclampsia Flashcards
Why is PE important? (5)
- 6th leading cause of direct maternal deaths (6 deaths over 3 years)
- Commonest medical problem in pregnancy:
– Gestational hypertension = 10%
– PE = 2-5%
– Severe PE= 1%
– Eclampsia (2% death rate) - Leading cause of iatrogenic prematurity
- Immediate risks of eclampsia, stroke and heart failure
- Life-long risk of cvd
High risk factors (5)
Previous pre-eclampsia
Chronic hypertension
Autoimmune disease
Diabetes mellitus
Chronic kidney disease
Moderate risk factors (6)
Nulliparity
Age >40
Pregnancy interval >10yr
BMI >35
Family hx pre-eclampsia
Multiple pregnancy
Pathphys
Normal placentation (5)
- Trophoblasts invade maternal vessels
- Narrow spiral arteries remodelled
- Wide-bore low-resistance vessels
deliver large amounts of maternal blood - Nutrient and oxygen delivery to fetus
PE implantation (7)
- Deficient trophoblast invasion
- Spiral arteries not remodelled
- High-resistance placental bed
- Poorly perfused hypoxic placenta
- Deficient nutrient and oxygen delivery
- Release of inflammatory cytokines (IL, TNF etc)
- Maternal endothelial dysfunction:
– Increased vascular reactivity and vasospasm
– Increased capillary permeability + reduced intravascular volume
ALTERNATIVE HYPOTHESIS:
CARDIOVASCULAR DYSFUNCION
look over
Common end pathway (2)
- Endothelial injury
- Vasoconstriction
Maternal effects of PE (4)
– Cerebral oedema: eclampsia
– Vasospasm: hypertension, renal failure
– Endothelial injury: low
platelets, disseminated
intravascular coagulopathy (DIC)
– Albumin leakage: proteinuria,
pulmonary oedema
Fetal effects of PE
– Growth restriction
– Prematurity
– Placental abruption
– Fetal death
Prevention (3)
Indication for Aspirin: 1 high or >1 moderate
Aspirin dose: 75-150mg
Aspirin duration: from 12w - Daily until delivery
screening + prediction 1st trim: (6)
after initial risk factor checks
* Age: every 10 years above 30 y
* Weight: every 10 kg above 70 kg
* Racial origin: Afro-Caribbean, South Asian
* Obstetric history: 1st pregnancy
* Family history of PE
* Autoimmune : SLE / APS
NICE risk-factor screening= 40.8% (32.8 – 48.9)
Maternal factors (MF)= 41.5% (33.3 – 50.1)
MF + Mean arterial pressure (MAP)= 49.3% (40.8 – 57.8)
MF + MAP + PAPP-A= 52.8% (44.3 – 61.2)
MF + MAP + PAPP-A + UtA-PI= 76.1% (68.2 – 82.8)
MF + MAP + PlGF + UtA-PI= 81.7% (74.3 – 87.7)
Classification of hypertension in preg. (4)
No proteinuria:
- <20/40 = pre-existing HTN
->20/40: gestational HTN
Significant proteinuria:
- <20/40 = pre-existing HTN, secondary to renal disease
->20/40: PE
Diagnostic criteria (5)
1) Hypertension Threshold: >140/90 mmHg
2) Hypertension Baseline Normotensive: <20 weeks (BUT can have superimposed PE on
background of Chronic HTN)
3) Proteinuria: >300 mg/24 hrs OR Protein:Creatinine ratio (PCR) >30 mg/mmol
OR +2 urine dipstick
4)Proteinuria a prerequisite for diagnosis= No
5)Other clinical criteria for diagnosis: Yes
- Renal Creatinine >90 μmol/litre
- Liver Liver enzymes: ALT or AST >40 IU/L, +/- RUQ or epigastric pain
- Neurological Eclampsia, altered mental status, blindness, stroke, clonus, severe
headaches or persistent visual scotomata
- Haematological Platelets <150,000 x 10 9 /L, Disseminated Intravascular
Coagulopathy (DIC) or haemolysis
- Uteroplacental Fetal growth restriction, abnormal umbilical artery Doppler waveform analysis, or stillbirth
SIGNS AND SYMPTOMS (9)
- No symptoms
- Headaches
- Flashing lights
- Epigastric pain
- Nausea/vomiting
- Confusion
- Hypertension
– Use the right cuff size
– Disappearance of sounds - Proteinuria
- Brisk jerks
PE INVESTIGATIONS (7)
- 24-hr urinary protein OR spot protein:creatinine ratio
- Platelet count
- LFT - Liver enzymes(ALT)
- U&E - Creatinine
- Clotting tests
- sFlt-1:PlGF ratio
- Fetal assessment –Ultrasound for growth and Dopplers +/- CTG
sFlt-1:PlGF ratio explained
sFlt-1:PlGF for antenatal management
estimation of risks study (4)
- Aim to identify the risk of fatal or life-threatening complications w/ PE within 48hr of hospital admission for disorder
- Internally and externally validated
- Outcome of interest was maternal mortality or other serious complications of PE
- Predictors of adverse maternal outcome included gestational age, chest pain or
dyspnoea, oxygen saturation, platelet count, and creatinine and aspartate
transaminase concentrations. - AUC ROC 0·88, 95% CI 0·84–0·92
A threshold of ≥30% risk is suggested as a threshold to rule-in the outcome.
Bp management (5)
BP Target = (130 – 140)/
(80 – 90)
- 1st Line = Labetalol (CI Asthma, Ischemic Heart Disease), Max 2g/day (500mg qds)
- 2nd Line = Nifedipine (CI Aortic Stenosis), Max 80mg/day (20-30mg tds)
- Consider = MethylDopa (CI Depression), Max 3g/day (1000mg tds)
BP = CO x TVR
CO = HR x SV:
SV relatively constant in 2nd-3rd trimester so HR will be driver for changes in CO
Home BP monitoring benefits (3)
- Safe and cost effective
- Reduction in induction of labour, antenatal admissions and PE diagnosis
- No compromise of maternal and pregnancy outcomes
Why not deliver? (4)
- Complications of prematurity
- Possibility of failed induction needing C section
- Attempts to prolong pregnancy are justified for pre-term PE
- Severe uncontrolled PE needs delivery after stabilisation
Severe PE (3)
- Diastolic BP ≥ 110 mm X 2
- Systolic BP ≥ 160 mm X 2 and ≥ ++ proteinuria
Signs or symptoms of imminent eclampsia
– Hyper-reflexia (neuronal irritability)
– Frontal headache
– Blurred vision (cerebral vasospasm)
– Epigastric tenderness (tension on liver capsule)
Prevention of Seizures (4)
Mag. Sulfate w/ PE = red. risk of eclamptic risk
women allocated mag. sulfate has 58% lower risk
maternal mortailty rate lower in treatment group
reduced risk of placental abruption
For controlled PE, should the pregnancy be prolonged after
36+6 weeks?
No- Authors concluded that induction of labour is recommended for women w/ mild PE or mild gestational hypertension at a gestational age beyond 37+0 weeks
For PE between 34 – 37
weeks, should delivery be considered?
yes - Authors concluded that between 34-36+6
weeks induction of labour should be considered for women w/ mild/moderate PE to reduce maternal
complications vs expectant to 37+0
weeks, but with higher chance of NNU
admission (due to prematurity)
But does earlier delivery cause harm?
yes + no - no stat. risk but slight variations and increases in neonatal Resp. distress + 2yr self-reports
Postnatal management (5)
- Carefully assess women with signs or symptoms of PE
- Assess need to continue anti-hypertensives
- Arrange appropriate follow-up
- An assessment of BP and proteinuria by the gp at the 6 weeks postnatal check is recommended
- If hypertension or proteinuria persists then further investigation is required.
PE effected postnatal management 920
- Women whose pregnancies have
been complicated by severe PE or eclampsia should be offered a formal postnatal review to discuss the events of the pregnancy. - Pre-conceptional counseling should
be offered where the events that occurred, any risk factors and any
preventative therapies can be discussed.
Pregnancy as stress test
Long term complications of PE (4)
Ischaemic heart disease
Stroke/VTE
Risk of mortality
Impact on baby:
* Higher systolic/diastolic BP
* Increased BMI
* Higher rates of pe in future
Summary (7)
- Recognise the importance of
(PE) - Understand the adverse maternal and fetal consequences
- Debate the aetiology of PE
- Define the risk factors and preventative strategies
- Describe the clinical definition PE
- Understand antenatal and postnatal management
- Discuss long term complications after PE
