Pre- & Eclampsia


re-Eclampsia Diagnosis

Triad of :

  • Hypertension
  • Proteinuria
  • Oedema. (usually insidious onset, asymptomatic)

Eclampsia usually occurs in first pregnancy unless change of partner.

  • Systolic BP > 160
  • Diastolic BP > 110 or (>15 mmHg above booking)
  • Proteinuria > "+" / 500 mg/24


  • Neurological - headache, visual disturbance and convulsions
  • Epigastric pain and tenderness
  • HELLP (Haemolysis, Elevated Liver enzymes and Low Platelets)
  • 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 only by delivery of the fetus (and placenta)


  • 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):
    1. Measure B.P. If > 140/90 mmHg seek advice from the obstetric unit in which the woman is booked
    2. 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
    3. Once admitted, blood should be analysed for, among other things, thrombocytopaenia and hepatic dysfunction
    4. If you remain concerned about the epigastric pain and tenderness in the absence of hypertension or proteinuria review the following day

Treatment of Eclampsia

  • High flow oxygen
  • Place in left lateral; position, suction available
  • i.v. access (large bolus)
  • Diazemuls 5 - 10 mg then
  • Magnesium

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), SpO2, ECG for first hour
Mg toxicity
>5 loss of reflexes, flushing, diplopia, slurred speech
6 - 7.5 muscle paralysis, respiratory arrest
>12 cardiac arrest

Recurrent seizures after Mg

  • Treat with a further bolus of 2g
  • RSI with Thiopentone/ventilation
  • Treat hypertension(MgSO4may reduce BP otherwise, consider Hydralazine)

Content by Íomhar O' Sullivan 11/03/2004. Reviewed by Dr ÍOS. Last review Dr ÍOS 23/04/22.