Question
A patient with COVID-19 pneumonia presents with severe respiratory distress. Arterial blood gas analysis shows a PaO₂/FiO₂ ratio of less than 100 mmHg. What is the most appropriate ventilatory strategy?
| A. | Low PEEP, high tidal volume |
| B. |
High PEEP, low tidal volume |
| C. |
Low tidal volume, low PEEP |
| D. |
High tidal volume, high PEEP |
|
Correct Answer » B Explanation |
 |
A PaO₂/FiO₂ ratio less than 100 mmHg indicates severe Acute Respiratory Distress Syndrome (ARDS) according to the Berlin definition.
COVID-19 pneumonia can progress to ARDS, characterized by:
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Diffuse alveolar damage
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Reduced lung compliance
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Severe hypoxemia
-
Bilateral infiltrates on chest imaging
Management requires lung-protective ventilation.
The recommended ventilatory strategy in ARDS is:
Low tidal volume ventilation (4–6 mL/kg predicted body weight)
This reduces volutrauma and barotrauma.
High PEEP
This prevents alveolar collapse at end-expiration, improves oxygenation, and reduces shunt.
This lung-protective strategy:
-
Improves survival
-
Reduces ventilator-induced lung injury
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Minimizes overdistension of alveoli
Therefore, the correct answer is high PEEP with low tidal volume.