Eclampsia

Introduction

Eclampsia is the occurrence of generalized convulsions, associated with signs of pre-eclampsia during pregnancy, labour, or within 7 days of delivery; not anticoagulation.
It is referred to as atypical eclampsia if it occurs

  • In the absence of high blood pressure
  • After 7 days post-partum

Its incidence is widely variable. Worldwide range is reported to be 1 in 100 to 1 in 3,448 pregnancies. In Nigeria, it is commoner among un-booked patients.

Aetiology

Not exactly known. Its precursor is preeclampsia. A disease of primigravidae, or multigravidae with pregnancy for a new consort.

Clinical features

Generalized tonic-clonic seizures, usually heralded by:

  • Headaches
  • Dizziness and blurring of vision
  • Nausea and vomiting
  • Epigastric pain
  • Rapidly progressive edema.
  • Exaggerated tendon reflexes.
  • Oliguria
  • Hypertension.
  • Worsening proteinuria

Complications

Maternal

  • Cerebral haemorrhage
  • Disseminated intravascular coagulopathy
  • Renal failure
  • Cardiopulmonary failure
  • Liver dysfunction (as in HELLP syndrome)
  • Fatality

Fetal

  • Prematurity
  • Intrauterine growth restriction.
  • Intrauterine fetal death.
  • Fetal brain damage

Differential diagnoses

  • Idiopathic epilepsy: sometimes.
    accompanied by transient proteinuria
  • Cerebral malaria: sometimes accompanied by hypertension and albuminuria
  • Pneumococcal meningitis
  • Hyper and/or hypo-glycaemia, particularly among diabetics.
  • Terminal phase of severe anaemia
  • Terminal phase of hepatic failure.
  • Severe infections and septicaemia.
  • Others:
    • Uremia
    • Brain tumours or abscesses
    • Cerebral haemorrhage
    • Poisoning (accidental or intentional)
    • Hysteria

Investigations

  • Haemoglobin concentration/ hematocrit
  • Haemoglobin genotype, Platelet count, Blood Group
  • Serum Urea and Electrolytes; Creatinine
  • Liver function tests
  • Urinalysis

Management

  • Manage in conjunction with the physician

Treatment objectives

  • Stabilise the patient
  • Deliver fetus by the safest and most expeditious route
  • Prevent complications

Stabilization

  • Control (and prevent further) fits
  • Control blood pressure
  • Maintain the airway
  • Ensure adequate urinary output
  • Monitor

Controlling fits

  • Intravenous diazepam -10mg stat
    to abort seizures or prevent fits during examination; then
  • Intravenous infusion of glucose 5% in water with 40 mg of diazepam added, and titrated against the patient’s level of consciousness
  • Magnesium sulfate (see details below)
  • Treatment packs are contained in cardboard boxes containing magnesium sulfate for the loading
    dose, 24hour maintenance therapy and treatment of one (recurrent) convulsion.
  • Syringes, swabs, drip sets and fluids also contained in treatment packs.;
  • Calcium gluconate should always be available to manage toxicity

Intravenous infusion of magnesium sulfate

  • Loading dose: 4 g by slow intravenous injection over a period not less than 5 minutes (preferably over 10-15 minutes)
  • Maintenance: 10 g in 1 litre of sodium chloride 0.9%, given by intravenous infusion at a rate of 1g per hour
  • The intramuscular magnesium sulfate (Pritchard) regimen
  • Loading dose: 4 g by slow intravenous injection over a period not less than 5 minutes, then 10 g intramuscularly, 5 g by deep intramuscular injection into each buttock
  • Maintenance therapy: 5 g by deep
    intramuscular injection, 2.5 g in each buttock every 4 hours
  • Continue for 24 hours after last
    convulsion, or delivery.

Recurrent convulsions

Magnesium sulfate

  • Give 2 – 4g intravenously over 5 minutes
  • Give lower dose (2 g) if the patient is small and/or weight is less than 70 kg
  • Monitoring during magnesium sulfate therapy
  • Continue with intravenous infusion or give the next intramuscular dose only if
    • Patellar reflexes are normal
    • Respiratory rate is> 16 cycles/minute
    • Urine output is > 25 mL/hour (or > 100 mL in 4 hours)
  • Consider reducing the dose if
    • Renal function is impaired
    • Respiratory depression occurs
    • Urine output is <100 mL in 4 hours
  • More frequent monitoring is required in the first two hours on intravenous therapy

Magnesium toxicity
Absent patellar reflexes:

  • Stop magnesium sulfate treatment
  • Administer oxygen by face mask
  • Administer 1g calcium gluconate by slow intravenous injection.

If respiratory rate is abnormal:

  • Stop further magnesium sulfate

If there are no respiratory abnormalities or abnormal patellar reflexes:

  • Reduce the dose by half.

Respiratory arrest:

  • Stop magnesium sulfate treatment
  • Intubate and ensure ventilation (manage with the anaesthetist)
  • Calcium gluconate 1 g by slow intravenous injection.

Control of blood pressure

  • Intravenous hydralazine 5 mg bolus slowly over 15 minutes, stat.
  • Further boluses can be given every 20 – 30 minutes as long as diastolic blood pressure is 110 mg and above

Or:

  • Labetalol – 20 mg intravenously as a bolus
  • Repeat after 15- 20 minutes (if increasing the doses)

The airway:

  • Intermittent suction of the nostrils and oropharynx
  • Insert an airway

Urinary output:

  • In-dwelling Foley’s catheter for strict fluid input and output monitoring.

Monitoring:

  • Quarter-hourly vital signs
  • Record any further fits

Delivery

  • Induction of labour is the first option if the cervix is favourable, particularly if the patient is not yet in established labour
  • Can be done by the use of escalating
    doses of oxytocin infusion or with
    misoprostol tablets
  • Elective forceps delivery
    • Should be done if patient is in the second stage to reduce the stress and cardiovascular changes, especially peaks
      of elevated blood pressure that accompany expulsive efforts at this stagebin labour

Emergency Caesarean section is indicated when:

  • Cervix is unfavourable for induction
  • There is fetal distress
  • Patient is unconscious (unless delivery is imminent)
  • Vaginal delivery is unlikely within 6-8 hours from the onset of the first eclamptic fit and there is an obstetric indication for a Caesarean section

Post-partum

  • Continue parenteral anticonvulsant for another 24 hours after delivery (or after last seizure), whichever comes first

Prevention

  • Adequate antenatal, intrapartum and postpartum care.
  • Early detection of pregnancy-induced hypertension.
  • Aggressive management.
    • This is the ‘gold standard’ towards achieving good fetal and maternal outcomes
  • Re-occurrence
    • Occurs in 15.6% of cases
  • Adequate counselling on the need for early booking, regular antenatal clinic attendance and hospital delivery in subsequent deliveries required.