M13Altered consciousness, eclampsia, movement disorders, stroke and trauma

Clinical overview

Altered consciousness or seizure in pregnancy is eclampsia until urgently considered and treated, but not every event is eclampsia. Hypoglycaemia, hypoxia, stroke, cerebral venous sinus thrombosis (CVST), PRES, RCVS, infection, toxic/metabolic disease, epilepsy, trauma and intracranial haemorrhage may coexist with hypertension or mimic it. The safe approach is simultaneous airway/physiology support, glucose correction, eclampsia treatment when plausible and rapid neurological evaluation.

Maternal stabilisation comes first in trauma and stroke. Necessary CT, CT angiography, MRI, thrombolysis, thrombectomy, surgery or antidote treatment is not withheld solely because of pregnancy. Minimise exposure and involve specialists, but do not allow fetal assessment to delay treatment of maternal hypoxia, hypotension, haemorrhage or brain injury.

Core knowledge

The unconscious patient

Use GCS or a similarly structured measure and record components, not only a total. Check airway protection, breathing pattern, pupils, eye position, focal motor signs, neck stiffness, clonus, temperature, rash and trauma. Capillary glucose is immediate. Review gestation/postpartum day, blood pressure, headache/visual symptoms, seizure timing, anaesthesia, medicines/toxins, infection, anticoagulation and blood loss.

Mechanisms include structural brain disease, diffuse metabolic/toxic dysfunction, seizure/postictal state and sedation. A focal deficit, unequal pupils or sudden maximal headache points toward structural pathology, but diffuse presentations can also be stroke or venous thrombosis.

Eclampsia and severe hypertensive disease

Eclampsia is a generalised seizure associated with pre-eclampsia after other causes are considered. It can occur antenatally, intrapartum or postpartum and may present without previously documented hypertension/proteinuria. Management priorities are lateral positioning, airway/oxygen support, protection from injury, magnesium sulphate, control of severe hypertension, evaluation for complications and delivery after stabilisation if still pregnant.

Use the exact South African 2026 magnesium regimen set out in M12: 4 g IV over 20 minutes, then 1 g/hour IV in high care or the specified IM alternative; an additional 2 g IV over 10 minutes for a recurrent seizure after loading. Monitor respiratory rate, reflexes and urine output; stop and treat toxicity with calcium gluconate as specified.

Do not repeatedly administer benzodiazepines instead of magnesium for ordinary eclampsia. If seizure persists despite adequate magnesium or the diagnosis is uncertain, treat as refractory status epilepticus with anaesthesia/neurology support while investigating intracranial disease and metabolic causes.

Typical adult second-line starting points — always against your unit's card — are lorazepam 4 mg IV over 2–5 minutes (repeatable once), phenytoin 15–20 mg/kg IV over 30 minutes to a maximum load of about 1.5 g, sodium valproate 25 mg/kg over 1 hour where appropriate, and thiopentone 2–3 mg/kg IV or a propofol infusion once the airway is secured. Valproate carries fetal risk and is avoided in pregnancy where an effective alternative exists — but status must never go untreated for want of an agent.

PRES commonly presents with headache, visual symptoms, seizure and encephalopathy in hypertensive disease; MRI is more sensitive, but acute management cannot wait for MRI when CT is needed to exclude haemorrhage. RCVS may cause recurrent thunderclap headache and stroke, often postpartum. The syndromes can overlap.