Background: Caffeine overdose can cause life-threatening circulatory failure, neurological abnormalities, and ventricular fibrillation.We report the case of a patient with caffeine poisoning who was successfully treated with early hemodialysis and venoarterial extracorporeal membrane oxygenation.Case Presentation: A 43-year-old man who had ingested pills containing 20 g caffeine was transported to the hospital 100 min after ingestion. Hemodynamic collapse and refractory arrhythmia were most likely the potential complications. The patient developed ventricular fibrillation when placed in the left lateral decubitus position. Return of spontaneous circulation with defibrillation and introduction of venoarterial extracorporeal membrane oxygenation were followed by emergency dialysis, which led to rapid improvement in the clinical findings. Conclusion:Acute caffeine poisoning in a patient who developed an arrhythmia was successfully treated using an indwelling arterial and venous sheath followed by venoarterial extracorporeal membrane oxygenation.

Herein, we present a case of heatstroke encephalopathy with abnormal brain magnetic resonance imaging (MRI) signals. A 19-year-old man lost consciousness while working outdoors when the temperature was 35°C. His Glasgow Coma Scale score at presentation was E1V1M1, and his body temperature was 39°C. Chest computed tomography revealed bilateral infiltrates, and tests for urinary pneumococcal antigens were positive. He was diagnosed with heatstroke preceded by pneumococcal pneumonia. He was subsequently treated with antibiotics, and body surface cooling was performed. A diffusion-weighted brain MRI performed on day eight revealed abnormal bilateral hyperintensities from the cortex at the frontal lobe apex of the subcortex. Moreover, he had reduced spontaneity, dysarthria, nystagmus, tremor, and ataxia of both the upper limbs. He was diagnosed with heatstroke encephalopathy. On day 28 since admission, the abnormal MRI signals disappeared. Subsequently, the patient’s spontaneity improved, but his other neurological dysfunctions persisted. This case study demonstrates that MRI may not be a sensitive indicator of the prognosis of heatstroke encephalopathy.