Preeclampsia diagnosis and management — structured SAQ (15 marks)

(a) Diagnosis and criteria (2 marks)

One mark for the diagnosis, one for naming the criteria met. ^[1][2]

• Preeclampsia with severe-range hypertension at 33+5 weeks.^[1]
• ISSHP 2021 criteria met: de novo hypertension after 20 weeks, plus significant proteinuria (protein:creatinine ratio 88 mg/mmol, threshold 30 mg/mmol or more), plus a neurological criterion (severe headache and clonus).^[1]
• By ACOG PB 222 she also has severe features: systolic 160 mmHg or more and diastolic 110 mmHg or more, plus new-onset headache unresponsive to medication.^[2]

(b) The first hour (6 marks)

One mark each for: recognition and time target; a named antihypertensive with dose, route and ceiling; magnesium with loading and maintenance dose; fluid restriction; investigations and fetal assessment; corticosteroids and escalation. ^[2][4]

• Investigations: full blood count, creatinine and electrolytes, liver enzymes, urate, lactate dehydrogenase, coagulation screen, group and hold, repeat protein:creatinine ratio.^[1][2]
• Fetal assessment: continuous cardiotocography, ultrasound for growth, liquor and umbilical artery Doppler.^[1]
• Escalation: admit to a high-dependency area, inform the obstetric consultant, obstetric physician, anaesthetist and neonatal team; insert a urinary catheter and start a strict fluid balance chart.^[2][3]
• Quote the evidence for magnesium: Magpie randomised 10,141 women and reduced eclampsia by 58% (0.8% versus 1.9%), with a probable reduction in maternal death.^[4]

(c) Interpreting the bloods (3 marks)

One mark for correctly mapping each abnormality to its criterion, one for the severity implication, one for the further investigations. ^[1][9]

• Platelets 84 x 10^9/L — below the ISSHP haematological threshold of 150 x 10^9/L, and below the ACOG severe-feature threshold of 100 x 10^9/L.^[1][2]
• ALT 96 IU/L — above the ISSHP hepatic threshold of 40 IU/L; combined with epigastric pain this raises HELLP syndrome.^[1]
• Creatinine 104 micromol/L — above the ISSHP acute kidney injury threshold of 90 micromol/L.^[1]
• Implication: multi-organ involvement, so this is severe disease and expectant management is now unsafe. Use fullPIERS to frame prognosis — its variables are gestational age, chest pain or dyspnoea, oxygen saturation, platelet count, creatinine and aspartate transaminase, with an area under the ROC curve of 0.88 for adverse maternal outcomes at 48 hours.^[9]
• Further investigations: lactate dehydrogenase, bilirubin, haptoglobin and a blood film for haemolysis; coagulation screen with fibrinogen; repeat full blood count and liver enzymes every 6 to 12 hours; liver imaging if the epigastric pain is severe or radiates to the shoulder.^[1][2]

(d) Timing and mode of birth (4 marks)

One mark for the decision, one for PHOENIX, one for the counterbalancing trials, one for mode and intrapartum specifics. ^[5][6][7]

• Decision: plan birth now. She has multi-organ involvement at 33+5 weeks, so this is not the elective 34 to 37 week shared-decision scenario — maternal indication overrides gestation. Give the first corticosteroid dose but do not delay birth for the second if she deteriorates.^[2][8]
• PHOENIX (Lancet 2019; 901 women, 34 to under 37 weeks): planned delivery reduced the maternal composite of morbidity or a recorded systolic of at least 160 mmHg from 75% to 65% (adjusted relative risk 0.86), while the perinatal composite of death or neonatal unit admission rose from 34% to 42% (relative risk 1.26) — driven by admissions for prematurity, not by greater neonatal morbidity.^[5]
• HYPITAT-II (Lancet 2015; 703 women with non-severe disease at 34 to 37 weeks): immediate delivery did not significantly reduce the maternal composite (1.1% versus 3.1%) but tripled respiratory distress syndrome (5.7% versus 1.7%) — which is why routine immediate birth is not justified for non-severe late-preterm hypertensive disease. HYPITAT (Lancet 2009): beyond 36 weeks induction reduced the poor maternal composite from 44% to 31%.^[6][7]
• Mode: decided obstetrically. Induction is reasonable with a favourable cervix and a reassuring fetus; caesarean for the usual obstetric indications or if she deteriorates. Intrapartum: continuous monitoring, early epidural if the platelet count and coagulation allow (most anaesthetists accept a stable count above roughly 75 to 80 x 10^9/L), fluid limits maintained, oxytocin rather than ergometrine for the third stage.^[2][1]