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Pre eclampsia and eclampsia

Pre eclampsia is a disorder of widespread vascular endothelial malfunction that occurs beyond the 20th week of gestation. It is characterised by increased blood pressure (BP) in an individual who was normotensive prior to the pregnancy, and proteinuria or excessive edema. In pregnant patients with hypertension pre eclampsia can occur.

  • Pre eclampsia is traditionally defined as two measurements greater than 140 systolic / 90 diastolic 4-6 hours apart.

  • Severe pre eclampsia is BP of 160 systolic over 110 diastolic, significant proteinuria, oliguria with less than 500 mL per 24 hours; cerebral or visual disturbance; pulmonary edema or cyanosis; abdominal pain; impaired liver function; thrombocytopenia; or decreased fetal growth.

  • Hemolysis, elevated liver enzyme levels, and low platelet count (HELLP) syndrome can be a first presentation of pre eclampsia.

If suspected, management is reassurance, symptom control and referral and, as with any significant problems of late pregnancy, call for help and advice. If a pregnant patient presents with hypertension, then immediate workup should ensue, beginning with a repeat measurement and early discussion with Obstetrics and Gynaecology.
Eclampsia presents with:
  • New onset of grand mal seizure

  • Unexplained coma

  • During pregnancy or postpartum in a woman with signs or symptoms of preeclampsia

  • But…beware, eclampsia in the absence of HT and proteinuria in a significant population (around 20%)


  • CNS, Headache, visual disturbances - blurred, scintillating scotomata, altered mental status, blindness - may be cortical or retinal

  • Dyspnea

  • Oedema - Exists in many pregnant women but sudden increase in oedema or facial oedema is more concerning for pre eclampsia

  • Epigastric or right upper quadrant (RUQ) abdominal pain


  • Increased BP compared with the patient's baseline or greater than 140/90

  • Tachypnea

  • Altered mental status

  • Decreased vision

  • Rales

  • Epigastric or RUQ abdominal tenderness

  • Peripheral oedema

  • Seizures

  • Focal neurologic deficit


  • CBC, microangiopathic hemolytic anemia (HELLP) Thrombocytopenia.

  • Liver function tests: elevated from hepatocellular injury and in HELLP syndrome.

  • Serum creatinine: ellevated due to decreased intravascular volume and decreased GFR.

  • UA, proteinuria> 1+ protein on dip.

  • Elevated PT, aPTT, fibrin split products, and decreased fibrinogen, consider DIC.

  • Uric acid Uric acid levels are increased in preeclampsia, serial levels may be useful to indicate disease progression.

  • Imaging:

  1. Head CT for focal neurological findings.

  2. U/S and CTG for fetal well being.


Pre-eclampsia/eclampsia has significant morbidity and mortality for mother and baby. Seek help early, approach systematically as with any emergency ABCDs and in the left decubitus position.

  1. Seizures are controlled with magnesium, 4gms slow bolus and then 1-2 gms/hr titrated to respiratory rate and reflexes. Refractive seizures use midazolam.

  2. Blood pressure is managed when extreme i.e. over 160 systolic and 105 diastolic , aim for around 140/90, using:

    1. hydralazine 5-10 mg IV titrated 20 minutely ( max 30 mg) OR
    2. labetalol 20 mg IV over 2 minutes, titrated 10 minutely ( max 80 mg)


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