Definition
- Failure of oxygenation and/or failure of ventilation, resulting in a failure to maintain normal levels of oxygen and carbon dioxide in the blood
Classification
- Type 1: inability to meet patient’s oxygen demands resulting in hypoxia
- Type 2: inability of CO2 clearance, typically resulting in hypercapnia. Severe hypercapnia may lead to hypoxia.
- V/Q (ventilation-perfusion) relationship is approximately 0.8 normally.
- A-a gradient = alveolar PO2 – arterial PO2.