Preeclampsia vs Eclampsia vs HELLP: NCLEX Must-Know Differences
By an RN · High-yield maternity topic
The 10-second versionPreeclampsia = hypertension + proteinuria after 20 weeks. Eclampsia = preeclampsia plus seizures. HELLP = Hemolysis, Elevated Liver enzymes, Low Platelets. Magnesium sulfate prevents/treats seizures — know its toxicity signs and antidote cold.
Diagnostic criteria
| Criteria |
|---|
| Preeclampsia | BP ≥140/90 on two readings + proteinuria (≥300 mg/24 hr), after 20 weeks gestation |
| Severe features | BP ≥160/110, platelets <100,000, LFTs 2× normal, pulmonary edema, severe headache, visual changes, new renal insufficiency, RUQ/epigastric pain |
| Eclampsia | Preeclampsia + new-onset seizures (no other cause) |
| HELLP | Hemolysis · Elevated Liver enzymes · Low Platelets — can occur with or without obvious HTN |
Magnesium sulfate — the drug the NCLEX loves
- Purpose: seizure prophylaxis in severe preeclampsia; seizure treatment in eclampsia. (It is not primarily a blood pressure drug.)
- Therapeutic range: 4–7 mEq/L.
- Toxicity signs — check these first: decreased/absent deep tendon reflexes (earliest), decreased respirations, decreased urine output, hypotension, flushing, drowsiness.
- Antidote: calcium gluconate or calcium chloride — keep it at the bedside.
- Assessments on MgSO4: DTRs, respiratory rate, urine output (must be ≥30 mL/hr), BP, magnesium levels, fetal monitoring.
Priority nursing actions
- Seizure precautions: padded side rails, suction and oxygen at bedside, quiet dark room, no stimulation.
- Positioning: left lateral — improves uteroplacental perfusion and reduces vena cava compression.
- During a seizure: stay with the patient, time it, protect from injury, never restrain or force anything into the mouth. After: assess airway, vitals, fetal status.
- Definitive treatment: delivery of the baby — everything else stabilizes until delivery is possible.
- Strict I&O and seizure monitoring; report headache, visual changes, RUQ pain, or decreased urine output immediately.
What the NCLEX actually asks
- First sign of MgSO4 toxicity → loss of deep tendon reflexes. First action → stop the infusion, notify provider, prepare calcium.
- Eclamptic seizure in progress → priority is airway and safety, then magnesium per orders.
- HELLP without hypertension → still HELLP. RUQ pain + low platelets in a pregnant patient should ring the bell.
- Don't confuse with chronic HTN: preeclampsia is new HTN after 20 weeks.
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