EMed

Pre- & Eclampsia

Background

Pre-Eclampsia Diagnosis

  • New-onset ↑BP (SBP≥140, DBP≥90) in > 20 weeks' gestation plus
  • Proteinuria or
  • Other maternal organ or uteroplacental dysfunction

Severe pre-eclampsia usually occurs in first pregnancy unless change of partner.

  • SBP > 160
  • DBP > 110 or (>15 mmHg above booking)
  • Proteinuria > "++" / 300 mg/24

Clinical

  • Neurological:
    • Headache
    • Visual disturbance
    • Convulsions
  • Epigastric pain and tenderness
  • HELLP:
    • Haemolysis
    • Elevated
    • Liver enzymes &
    • Low Platelets

Notes

  • Pre-eclampsia as a syndrome specific to pregnancy
  • Disorder of endothelial function (placental / maternal vascular trees)
  • 20% of maternal mortality
  • Commonest recognised cause of fetal growth retardation
  • Fitting due to pregnancy induced hypertension
  • May be atypical
  • May occur post partum
  • Progress halted by delivery (foetus & placenta)

Approach

  • Upper abdominal pain in pregnancy may indicate pre-eclampsia

All women who present with upper abdominal pain and tenderness in pregnancy (usually after 20 weeks' gestation):

  • Measure B.P. If > 140/90 mmHg seek advice from the obstetric unit in which the woman is booked
  • Test for proteinuria. If proteinuria (i.e., more than a trace) is present in an MSU and especially if hypertension is detected refer immediately for admission to the maternity unit. (Don't take "No" for an answer
  • Once admitted, blood should be analysed for, among other things, thrombocytopaenia and hepatic dysfunction
  • If you remain concerned about the epigastric pain and tenderness in the absence of hypertension or proteinuria ask a senior to review

Management of severe pre-eclampsia

  • Call Obs/Gyn early
  • Left lat. position, suction available
  • i.v. access (avoid fluid loading)
  • Severe ↑BP Mx

Initial Ix

  • U&E, creat.
  • FBC
  • LFTs
  • Clotting screen
  • Group & save serum
  • Urinalysis

Severe hypertension Management

  • SBP >160mmHg requires prompt treatment
  • Target: BP<135/85 (MAP <100)
  • Consider art. line before IV antihypertensive meds.
    • Patient stable
    • BP veryt high
    • Patient BMI↑ or non-invasive BP unreliable
    • Presence of haemorrhage (> 1000mL)

1st line: labetalol

  • 200mg PO ± repeat at 30min or
  • Bolus IV 50mg over 5 minutes
  • ± repeat bolus at 10min (max 200mg)
  • Labetalol infusion at 20mg/hr and titrate

2nd line: Hydralazine

  • Added only if max. Labetalol has not ↓BP and/or contraindicate
  • Consult a senior and Obs/Gyn. consultant involvement
  • Bolus: 2.5mg in 10mL H2O) over 5 min
  • ± repeat at 20min (max 20mg)
  • Infusion : 40mg in 40mLs NaCl at 1-5mL/hr

Eclampsia

  • New onset seizures in setting of pre-eclampsia
  • No other underlying cause for seizures

Aim to:

  • Prevent maternal hypoxia
  • Severe ↑BP management
  • Prompt delivery

Eclampsia Mx

  • ABC as above (left lat. position)
  • O2. Suction available
  • IV benzos if delay to Mg++
  • Give loading dose (4g IV over 15 mins) magnesium
  • Start Mg++ infusion and BP therapy (above)
  • If further seizures: further 2g Mg bolus
  • Consider intubation and other antiepilepyics
  • Involve Obs/Gyn. for safe delivery

Magnesium Sulphate

  • Contra-indications: neuromuscular disease, myasthenia gravis, renal failure, cardiac disease
  • MgSO4 Loading dose - 4 grams (8 mls 50% w/v) i.v. over 5 mins
  • Causes nausea, vomiting and flushing (use Maxolon)
  • Maintenance infusion of 1g/h for at least 24 hours after the last seizure
  • Recurrent seizures should be treated by a further bolus of 2g
  • Can cause respiratory arrest
  • Reduce maintenance dose in oliguria or renal failure

Magnesium toxicity

  • Antidote: Calcium Gluconate 1 gram over 10 mins
  • Monitor: reflexes, resps (>16/min), ECG for 1st hour
Mg toxicity
>5 loss of reflexes, flushing, diplopia, slurred speech
6 - 7.5 muscle paralysis, respiratory arrest
>12 cardiac arrest

Content by Íomhar O' Sullivan . Last review/edit by Dr Peter Cuthbert 19/02/25.