Oxygenation Failure Patterns

Oxygenation failure means that the lungs cannot transfer enough oxygen from the alveoli into arterial blood. In acute hypoxemic, or type I, respiratory failure, impaired gas exchange can produce a PaO₂ below 60 mm Hg and, in severe acute disease, a PaO₂/FiO₂ ratio below 200. The bedside pattern is more than a low monitor value. Watch the patient’s work of breathing, ability to speak, mental status, skin colour, haemodynamic stability, and response to oxygen. A falling SpO₂ with increasing effort is a deterioration pattern, even before the patient becomes visibly cyanotic. Oxygen is a bridge while the cause is assessed and treated. The nurse gives controlled oxygen, confirms the response, and escalates support when the patient remains hypoxemic or is tiring.