• Middle-aged man with myasthenia gravis presenting with marked bilateral ptosis, progressive lethargy and decreased breath sounds (all of which point to a myasthenic crisis that would lead to respiratory insufficiency and CO2 retention), who has acid-base findings of acidemia with increased PCO2 and normal HCO3, consistent with an uncompensated respiratory acidosis
• Key idea: If patient had chronic respiratory failure, HCO3 would be elevated because it would have had time to compensate over time

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