A 28-year-old primigravida at 34 weeks of gestation presents to the antenatal clinic with a blood pressure of 158/102 mmHg. She reports a 2-week history of persistent headache, epigastric pain, and visual disturbances. On examination, she has brisk reflexes with 3+ patellar reflexes bilaterally. Urine dipstick shows 3+ proteinuria. Platelet count is 95,000/μL, serum creatinine is 1.4 mg/dL, and AST is 78 U/L. What is the most appropriate immediate management?

Explanation

## Clinical Diagnosis: Severe Preeclampsia with Imminent Eclampsia This patient meets criteria for severe preeclampsia with severe features and is at high risk of eclampsia, requiring urgent intervention. ### Diagnostic Criteria Met | Feature | Value | Severity Indicator | |---------|-------|-------------------| | BP | 158/102 mmHg | ≥160/110 mmHg or ≥140/90 on 2 occasions | | Proteinuria | 3+ | ≥1+ on dipstick | | Platelets | 95,000/μL | <100,000 = severe feature | | Creatinine | 1.4 mg/dL | >1.1 = severe feature | | AST | 78 U/L | >2× ULN = severe feature | | Symptoms | Headache, epigastric pain, visual disturbances | Imminent eclampsia signs | | Reflexes | 3+ brisk | Hyperreflexia = eclampsia risk | **Key Point:** The combination of severe hypertension, thrombocytopenia, elevated transaminases, and neurological symptoms (headache, visual changes) defines **severe preeclampsia with severe features** at ≥34 weeks gestation. ### Management Algorithm for Severe Preeclampsia at ≥34 Weeks ```mermaid flowchart TD A[Severe Preeclampsia ≥34 weeks]:::outcome --> B{Maternal/fetal stability?}:::decision B -->|Stable| C[Administer MgSO4 for seizure prophylaxis]:::action B -->|Unstable/eclampsia risk| C C --> D[Initiate antihypertensive therapy]:::action D --> E[Plan delivery within 24-48 hours]:::action E --> F[Corticosteroids if <34 weeks]:::action E --> G[Delivery at ≥34 weeks]:::action G --> H[Vaginal delivery preferred if stable]:::action H --> I[Cesarean if obstetric indication]:::action ``` **High-Yield:** At ≥34 weeks with severe preeclampsia, **delivery is the definitive treatment**. Do NOT delay for expectant management. ### Why Magnesium Sulphate? 1. **Seizure prophylaxis:** Reduces eclampsia risk by ~50% (NNT = 100) 2. **Neuroprotection:** In preterm pregnancies (<32 weeks), reduces cerebral palsy risk 3. **Mechanism:** NMDA receptor antagonism, stabilizes neuromuscular junction 4. **Dosing:** 4 g IV loading over 20 min, then 1 g/hour infusion for ≥12 hours postpartum **Clinical Pearl:** Magnesium sulphate is NOT an antihypertensive—it is a seizure prophylactic. Antihypertensives (nifedipine, labetalol, hydralazine) are given concurrently for BP control. ### Antihypertensive Therapy **First-line agents in pregnancy:** - **Labetalol:** 10–20 mg IV, then 40–80 mg every 10 min (max 220 mg) - **Nifedipine (immediate-release):** 10–20 mg PO, repeat every 20–30 min - **Hydralazine:** 5–10 mg IV every 20 min (slower onset, less predictable) **Target:** Reduce MAP by 15–25% in first hour; avoid excessive reduction (risk of placental hypoperfusion). ### Delivery Plan at ≥34 Weeks - **Timing:** Delivery within 24–48 hours after stabilization - **Route:** Vaginal delivery preferred if no obstetric contraindication and maternal condition stable - **Anesthesia:** Epidural preferred (avoid general if possible—risk of aspiration, airway edema) - **Corticosteroids:** NOT indicated at ≥34 weeks (fetal lung maturity assumed) **Warning:** Do NOT use ACE inhibitors, ARBs, or atenolol in pregnancy—teratogenic or associated with fetal complications. **Mnemonic: HELLP Syndrome (subset of severe preeclampsia)** — **H**emolysis, **E**levated **L**iver enzymes, **L**ow **P**latelets. This patient has features of HELLP (thrombocytopenia, elevated AST), which mandates urgent delivery. [cite:Williams Obstetrics 26e Ch 34]