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Respiratory failure from obesity hypoventilation — SCE Acute Medicine MCQ

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EasyAcute Respiratory PresentationsRespiratory failure from obesity hypoventilationSCE Acute Medicine

A 59-year-old woman is assessed on the acute medical unit. She has morbid obesity, somnolence and oedema. ABG shows pH 7.27, PaCO2 10.4 kPa and bicarbonate 36 mmol/L without focal consolidation. Initial assessment includes relevant observations, bedside tests and urgent blood results. What is the most appropriate next step in management?

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Correct answer: E — Start non-invasive ventilation on the acute unit

Start non-invasive ventilation on the acute unit is the best answer because acute-on-chronic ventilatory failure in obesity hypoventilation with acidaemia should be treated with NIV. Insert a large-bore chest drain using image guidance is plausible, but it is less appropriate for the physiology or timing described in this stem. The other distractors either fit a neighbouring presentation, delay definitive treatment, or miss the key immediate risk. Clinical pearl: A raised bicarbonate indicates chronic CO2 retention.

Reference: BTS/ICS acute NIV guideline