Severe falciparum malaria — recognition, severity grading and emergency management

Diagnosis: severe Plasmodium falciparum malaria. The non-immune traveller, presentation within the incubation window (7-30 days), classical paroxysm and the smear-confirmed 6 per cent parasitaemia are diagnostic. The coma, hyperparasitaemia, hypoglycaemia, AKI, acidosis, anaemia and jaundice together satisfy multiple WHO severity criteria.^[1][4]

Immediate assessment — ABCDE.

• Airway patent; protect in the drowsy patient (recovery position, suction).
• Breathing — high-flow oxygen to target SpO2 94 per cent or above; RR 32 with deep (Kussmaul) breathing indicates metabolic acidosis.
• Circulation — IV access x2; BP 96/60 — only enough crystalloid to restore perfusion, NOT aggressive resuscitation (pulmonary oedema/ARDS is lethal in malaria). Reassess with passive leg raise / IVC.
• Disability — GCS 10; bedside glucose 1.6 mmol/L (HYPOGLYCAEMIA — treat NOW); pupils, fundoscopy (malarial retinopathy), check for seizures.
• Exposure — full set of observations, abdominal exam (soft splenomegaly consistent with malaria), look for eschar (scrub typhus co-infection), rash (dengue), and bleeding (DIC).

Severity stratification — multiple WHO criteria for SEVERE malaria.^[4]

• Cerebral malaria — GCS under 11 without alternative cause.
• Hyperparasitaemia — 6 per cent (above the 2 per cent severe threshold for non-immune adults).
• Hypoglycaemia — glucose 1.6 mmol/L (below 2.2 mmol/L).
• Severe metabolic acidosis — bicarbonate 14, lactate 6.2 mmol/L (lactate over 5 is the strongest single mortality predictor).
• Acute kidney injury — creatinine 2.6 mg/dL.
• Severe anaemia — Hb 7.2 g/dL (close to the 7 threshold).
• Jaundice — bilirubin 4.5 mg/dL (over 3 mg/dL).
• Thrombocytopenia — 40 x10^9/L (supportive; common to all species).

Treatment — first 6 hours.^[2][3]

1. Treat hypoglycaemia NOW — 50 mL of 50 per cent dextrose IV (or 5 mL/kg of 10 per cent dextrose in a child), followed by an IV 10 per cent dextrose infusion at 1-2 mL/kg/h; recheck glucose every 30-60 minutes. Prefer artesunate over quinine to avoid quinine-driven hyperinsulinaemic hypoglycaemia.
2. IV artesunate 2.4 mg/kg at hour 0, 12 and 24, then once daily until oral therapy is tolerated. He weighs approximately 70 kg, so 168 mg IV per dose. Children under 20 kg need 3 mg/kg per dose. SEAQUAMAT (adults, 35 per cent relative mortality reduction) and AQUAMAT (African children, 22.5 per cent reduction) established artesunate as the global standard over quinine.^[2][3]
3. Admit to ICU; full monitoring: GCS hourly, glucose hourly (especially if quinine used), RR, SpO2, urine output (urinary catheter), repeat parasitaemia every 12 h until falling, daily U&E, LFTs, lactate, FBC.
4. Cautious IV fluids — balanced crystalloid in small aliquots (250-500 mL) reassessed for responsiveness; AVOID fluid boluses over 20 mL/kg (FEAST trial — excess mortality in African children). The Kussmaul breathing is acidotic, not hypovolaemic.
5. Severe anaemia — transfuse packed red cells (Hb under 7 g/dL or under 9 in pregnancy with decompensation); 10-20 mL/kg over 3-4 h with furosemide if volume-overloaded.
6. Acidosis — treat the cause (anaemia, hypovolaemia, sepsis); do NOT give bicarbonate routinely.
7. Empirical broad-spectrum antibiotics (e.g. ceftriaxone 2 g IV) — algid/severe malaria frequently co-presents with Gram-negative bacteraemia; send blood cultures.
8. Seizures — IV lorazepam 4 mg (repeated once) then IV levetiracetam or phenytoin. DO NOT give prophylactic phenobarbital (excess respiratory depression / mortality in cerebral malaria).
9. Exclude meningitis by LP once the patient is stable (after CT if focal signs or papilloedema).
10. Plan step-down — after at least 24 h of IV artesunate and falling parasitaemia, complete a 3-day oral course of ACT (artemether-lumefantrine 4 tablets BD for 3 days, with fatty food). Send FBC at week 2 and 4 for post-artemisinin delayed haemolysis.