A 69-year-old man has been ventilated for an infective exacerbation of chronic obstructive pulmonary disease (COPD). His ICU course has been complicated by septic shock and acute kidney injury that required renal replacement therapy. His therapy has included steroids and an aminoglycoside in addition to other standard care for his COPD.
12 days later neurological examination off sedation reveals spontaneous eye opening, obeying of commands, and normal cranial nerves. Motor examination of the limbs reveals symmetric reduction in tone and tendon reflexes with moderate to severe weakness. Plantar responses are equivocal. Sensory examination is normal. Examination of the chest and recent CXR are both unremarkable. He remains intubated with a spontaneous mode of ventilation (Pressure Support of 15, PEEP 7, FiO2 0.35). Attempts to wean pressure support have been poorly tolerated. Other vital signs and organ function remain stable.
1. List the differential diagnoses for his weakness and explain your reasoning.
The rest of the viva focussed on the diagnosis and management of critical illness neuromyopathy
Disclaimer: the viva stem above may be an original CICM stem, acquired from their publicly available past papers. Or, perhaps it is a slightly altered version of the original CICM stem. Or, it is a completely original viva stem, concocted by the monstrously amoral author of Deranged Physiology for nothing more than his own personal amusement. In either case, because the college do not make the main viva text or marking criteria available, almost everything here has been confabulated. It might sound like a plausible viva and it could be used for the purpose of practice, but all should be aware that it does not represent the "true" canonical CICM viva station.