Pre-eclampsia and eclampsia — exact 10-mark SAQ

Stem

A 32-year-old primigravida at 33+0 weeks has blood pressure 168/114 mmHg on two correctly measured readings 15 minutes apart. She has a severe frontal headache unrelieved by paracetamol and photopsia. Urine dipstick is 3+. She is alert, with brisk reflexes and three beats of ankle clonus. Oxygen saturation is 97% on room air and the chest is clear.^[1][5]

Questions

a) State the diagnosis and identify the scoreable severe features. (2 marks)^[1][5]

b) Give the immediate management before a final birth decision. (4 marks)^[1][5]

c) State four safety actions during magnesium sulphate therapy, including the response to toxicity. (2 marks)^[4]

d) Contrast the ACOG and NICE birth-timing approach at 33 weeks. (1 mark)^[1][5]

e) Give one region-specific prevention point and one postpartum safety point. (1 mark)^[1][5]

Model answer and reproducible marking key

a) Diagnosis and severe features — 2 marks

Award 0.5 mark for each criterion, maximum 2:^[1][5]

1. 0.5: Pre-eclampsia with severe features: new hypertension at or after 20 weeks with proteinuria or specified dysfunction.^[1][3]
2. 0.5: Persistent severe hypertension—systolic ≥160 mmHg or diastolic ≥110 mmHg; this patient meets both components.^[5]
3. 0.5: New persistent severe headache unresponsive to analgesia.^[5]
4. 0.5: Visual disturbance—photopsia.^[5]

Do not award a separate severe-feature mark for 3+ proteinuria: protein amount does not grade severity. Brisk reflexes or clonus may heighten neurological concern but are not stand-alone diagnostic severe-feature criteria.^[1][3]

ACOG threshold check (not an additional mark): the laboratory severe-feature boundaries are platelets <100 ×10⁹/L, serum creatinine >1.1 mg/dL or doubling in the absence of other renal disease, and transaminases ≥2 times normal.^[5]

b) Immediate management — 4 marks

Award 0.5 mark for each criterion, maximum 4:^[1][5]

1. 0.5: Admit to labour ward/HDU, call senior obstetric and anaesthetic teams, and prepare neonatal input.^[1]
2. 0.5: Rapid ABC assessment; left lateral positioning if consciousness falls or seizure occurs; check glucose. This alert, normally saturated, non-seizing patient does not need routine oxygen. If an active generalized eclamptic seizure occurs, give high-flow oxygen while protecting the airway and assessing ventilation under Hypertensive Disorders in Pregnancy - SA Perinatal Practice Guidelines.^[2]
3. 0.5: Establish IV access, measure BP frequently, catheterise for accurate urine output when indicated, and avoid unindicated fluid loading.^[1][3]
4. 0.5: Begin the local acute severe-hypertension bundle urgently. Accept IV labetalol, IV hydralazine or oral immediate-release nifedipine; do not accept sublingual nifedipine.^[5]
5. 0.5: Give magnesium sulphate for seizure prophylaxis using one complete named protocol; for example, NICE 4 g IV over 5–15 minutes then 1 g/hour, or ACOG 4–6 g over 20–30 minutes then 1–2 g/hour. Do not mix loading and maintenance schedules.^[4][5]
6. 0.5: Maternal tests: FBC/platelets, creatinine/electrolytes, AST/ALT and quantified urine PCR/ACR; add blood film, LDH, bilirubin, coagulation and group-and-screen if HELLP/DIC/delivery concern.^[1][3]
7. 0.5: Fetal assessment with CTG now and ultrasound growth, fluid and umbilical-artery Doppler when maternal stabilization permits.^[1]
8. 0.5: Senior birth decision after stabilization. Give antenatal corticosteroids if preterm birth is expected and time permits, but never delay an indicated birth for steroid completion. If HELLP is identified, birth is required after maternal stabilization regardless of gestation; individualize only immediate stabilization and route.^[1][5]

c) Magnesium safety — 2 marks

Award 0.5 mark for each criterion, maximum 2:^[1][4]

1. 0.5: Monitor respiratory rate and oxygen saturation at the local protocol interval.^[1]
2. 0.5: Check deep-tendon reflexes; loss of reflexes is an early clinical toxicity sign.^[1]
3. 0.5: Monitor hourly urine output and renal function; reduce/withhold maintenance and check serum magnesium when renal impairment or oliguria raises accumulation risk.^[1][3]
4. 0.5: If toxicity is suspected, stop magnesium, call for help and support airway/ventilation. The Queensland Clinical Guideline eclampsia flowchart specifies 10% calcium gluconate 10 mL IV over 5 minutes—equivalent to 1 g—under the emergency medicine protocol.^[5]

d) Birth timing at 33 weeks — 1 mark

Award 0.5 mark for each regional branch, maximum 1:^[1][5]

1. 0.5 ACOG: before 34 weeks, expectant management is considered only if severe hypertension is controlled, neurological symptoms resolve, maternal tests and fetal status are stable, and tertiary resources are available. Persistent symptoms, uncontrolled BP or deterioration requires birth after stabilization; steroids must not delay it.^[5]
2. 0.5 NICE: before 34 weeks, NICE NG133 generally continues surveillance unless a listed maternal or fetal threshold for planned early birth is met. Document thresholds and involve senior obstetric and neonatal teams; the presenting neurological symptoms and severe BP require reassessment after emergency treatment.^[1]

Do not award “wait automatically until 34 weeks.”^[1][5]

HELLP safety override (not an additional mark): once HELLP is identified, birth is required after maternal stabilization regardless of gestation. Corticosteroids must not postpone it; only the immediate stabilization steps and route of birth are individualized.^[1][5]

e) Prevention and postpartum safety — 1 mark

Award 0.5 mark for each criterion, maximum 1:^[1][5]

1. 0.5 prevention: one complete regional statement—for example, NICE aspirin 75–150 mg daily from 12 weeks until birth for one high-risk or more than one moderate-risk factor; or ACOG 81 mg daily from 12–28 weeks, optimally before 16 weeks, until delivery for eligible high-risk patients.^[1][5]
2. 0.5 postpartum: continue protocolised BP and symptom surveillance because disease can present or worsen after birth; accept NICE day 3–5 plus 6–8-week review, ACOG severe-BP review within 72 hours/all HDP by 7–10 days, or an equivalent named local pathway.^[1][5]

Mark total check

2 + 4 + 2 + 1 + 1 = exactly 10 marks. Every mark has a stated 0.5-point criterion; no unallocated list item earns credit.^[1][5]

References5ShowHide

1. [1]Wu P, Green M, Myers JE. Hypertensive disorders of pregnancy BMJ, 2023.PMID 37391211
2. [2]Fishel Bartal M, Sibai BM. Eclampsia in the 21st century American Journal of Obstetrics and Gynecology, 2022.PMID 32980358
3. [3]Magee LA, Brown MA, Hall DR, et al. The 2021 International Society for the Study of Hypertension in Pregnancy classification, diagnosis & management recommendations for international practice Pregnancy Hypertension, 2022.PMID 35066406
4. [4]Altman D, Carroli G, Duley L, et al. Do women with pre-eclampsia, and their babies, benefit from magnesium sulphate? The Magpie Trial Lancet, 2002.PMID 12057549
5. [5]American College of Obstetricians and Gynecologists. Gestational Hypertension and Preeclampsia: ACOG Practice Bulletin, Number 222 Obstetrics & Gynecology, 2020.PMID 32443079