Hypoxemia

This code signifies a lower-than-normal level of oxygen in the arterial blood. It indicates insufficient oxygenation of the blood, often a symptom of underlying respiratory or cardiovascular conditions.

Assign this code when documentation explicitly states "hypoxemia" or "low arterial oxygen." It is frequently used as a secondary diagnosis when the underlying cause of the hypoxemia is also documented and coded. Support for this code comes from arterial blood gas (ABG) results showing low PaO2 levels or pulse oximetry readings indicating significant desaturation.

• Do not code this as a primary diagnosis if the underlying cause (e.g., pneumonia, COPD exacerbation) is known and documented.
• Distinguish from hypoxia (R09.01), which refers to low oxygen levels in tissues, not specifically in the blood.
• Always sequence this code after the definitive diagnosis responsible for the hypoxemia, if identified.