Pre-eclampsia Flashcards
Definition of Pre-eclampsia
Hypertension of at least 140/90 mmHg recorded on 2 separate occasions at least 4 hours apart + presence of at least 300mg of protein in 24 hour urine collection. Occurs de novo after 20 wks gestations in previously normal women, resolves 6 wks postpartum
Superimposed Pre-eclampsia
Chronic HTN + pre-eclampsia
Risk factors of Pre-eclampsia
- First pregnancy
- Multiparous with Hx of pre-eclampsia or +10 years since last pregnancy
- Age (+40)
- BMI= +35
- Family Hx
- Booking Diastole BP of +80mmHg
- Booking proteinuria of +1 more than once or +0.3 per 24 hrs
- Multiple pregnancy
- Underlying medical condition: HTN
Renal disease
DM
Antiphospholipid antibodies
Cause of pre-eclampsia
unknown suggested that trophoblastic tissue is trigger
Pathophysiology
Trophoblastic invasion is patchy
Spiral arteries retain muscle wall (high resistance, low capacity).
Relative under perfusion of placenta releases factor that affects vascular endothelium in maternal circulation
Affects multiple systems
Effects of pre-eclampsia on CVS
1.Marked peripheral vasconstriction
2. INcreased intravascular pressure
3. loss of endothelial integrity
4. greater vascular permeability >generalized oedema
Effects of pre-eclampsia on Renal system
1.Glomeruloendotheliosis
Impaired glomerular filtration, loss of intermediate proteins like albumin + transferin -> proteinurea -> decrase in plasma oncotic pressure -> exacerbates oedema
Effects of pre-eclampsia in Haem system
Due to endothelial damage
* Platelets adhere to damaged area
*Diffuse Vascular damage + fibrin
Increase in fibrin and reduction in platelet may be sign of onset.
Effect of Pre-eclampsia on Liver
Increase in liver enzymes due to fibrin deposition
HELLP Syndrome
HELLP Syndrome
Haemolysis
Elevated Liver enzymes
Low Platelets
Severe form of pre-eclampsia
High rate of fatal loss (60%)
Effect of pre-eclampsia on Neuro system
Convulsions (eclampsia)
Vasospasm
Cerebral oedema
Retinal haemorrhage, exudate and papilloedema (usually characteristic of hypertensive encephalopathy not sign of pre-eclampsia)
Clinical Presentation of Pre-eclampsia
Frontal Headache
Visual Disturbance
Epigastric pain (liver involved)
Could be asymptomatic or flu-like symptoms
Pre-eclampsia examination
Complete obstetric and neurological examination.
Rapid oedema of face and hands
Dependant oedema -very common
Hypertension may be 1st sign but may appear late
Neuro-exam may show hyper-reflexia + clonus
Testing for proteinuria
Dipstick Urine Analysis
Protein- Creatinine Ratio
24 hour collection
Dipstick Urine analysis
Instant but inaccurate
Results:
Trace= seldom significant
1+ = possible significance
>=2+ = probable significance
Protein-creatinine ratio
Fast (1hr)
Result: semi-quantitative >30mg/mol
24 hour collection
Slow
Results
>0.3g/24hr = confirmed significant proteinuria
Maternal Investigations for pre-eclampsia
1.CBC
2.Serum Renal Profile
3.Serum Liver Profile
Fetal investigation for pre-eclampsia
U/S for size, amniotic fluid and Doppler
CTG
Function of antihypertensive
Decrease BP
Prevent CVA
Antihypertensive drugs given
1.Labetalol (oral/IV alpha and beta blocker)
2.Methyldopa (oral, central acting) slow, S:E depression or sedation
3.Nifedipine (oral Ca channel blocker ) rapid SE: headaches
4. Hydralizine= anticonvulsant, smooth muscle relaxant
In severe cases of pre-eclampsia give
Labetalol +Hydralazine infusion
Treatment for eclampsia
MgSO4 IV
Screening + Prevention of Pre-eclampsia
Screening : characterisitc notch on uterine artery in Doppler
Preventative: Low dose aspirin (75mg daily) for pt with hx
Premature delivery for pt w/pre-eclampsia by CS. Patient has a higher risk of ? and should be given?
MOther has higher risk of thromboembolism
Give prophylactic Heparin
