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Suspected Guillain–Barré syndrome with impending respiratory failure — MRCEM SBA MCQ

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EasyNeurological emergenciesSuspected Guillain–Barré syndrome with impending respiratory failureMRCEM SBA

A 46-year-old man presents with four days of worsening weakness in both legs, now extending to his hands, after a recent diarrhoeal illness. He can no longer walk unaided and has begun to cough weakly when drinking. Examination shows symmetrical limb weakness and absent tendon reflexes, without a sensory level. He is alert and maintaining his airway. His oxygen saturation is 98% on air, but his forced vital capacity is 1.1 L; he weighs 70 kg. What is the most appropriate immediate management plan?

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Correct answer: C — Request immediate critical care and neurology review with serial forced vital capacity measurements.

The progression of symmetrical, areflexic weakness over days is strongly suggestive of Guillain–Barré syndrome. His weak cough and difficulty swallowing add concern for bulbar and respiratory muscle involvement. A forced vital capacity of 1.1 L at 70 kg is approximately 16 mL/kg: below the 20 mL/kg level associated with serious respiratory risk. Normal oxygen saturation does not exclude impending neuromuscular respiratory failure. He needs immediate critical care assessment alongside neurological review, with repeated forced vital capacity measurements; the finding prompts assessment for ventilatory support, not automatic intubation. ([nice.org.uk](https://www.nice.org.uk/guidance/ng127/chapter/recommendations-for-adults-aged-over-16)) A lumbar puncture may contribute to the subsequent diagnostic assessment, but option A delays evaluation of the immediate respiratory threat. B includes appropriate monitoring but omits critical care review despite the low capacity and bulbar symptoms. Intravenous immunoglobulin in D may be appropriate after specialist assessment, but starting it does not replace respiratory escalation. Cervical spine MRI in E would gain priority if examination suggested cord disease, such as a sensory level or upper motor neurone signs; neither is present, and imaging must not delay respiratory assessment. ([nice.org.uk](https://www.nice.org.uk/guidance/ng127/chapter/recommendations-for-adults-aged-over-16))

Reference: Suspected neurological conditions: recognition and referral — recommendations for adults aged over 16 (2 October 2023) — https://www.nice.org.uk/guidance/ng127/chapter/recommendations-for-adults-aged-over-16 Weakness in the intensive care unit (2022) — https://pn.bmj.com/content/22/5/358 BTS guideline for oxygen use in adults in healthcare and emergency settings (2017) — https://thorax.bmj.com/content/72/Suppl_1/ii1