Mixed disorder of acid-base balance

This code signifies a complex physiological state where a patient exhibits more than one primary acid-base disturbance simultaneously, such as metabolic acidosis combined with respiratory alkalosis. It indicates that the body's compensatory mechanisms are either overwhelmed or contributing to a second, distinct acid-base derangement.

Use this code when documentation explicitly states a "mixed acid-base disorder" or identifies two or more primary acid-base disturbances occurring concurrently. This often requires interpretation of arterial blood gas (ABG) results and clinical context to determine the primary nature of each disturbance.

• Ensure documentation clearly specifies "mixed" or identifies multiple primary acid-base disorders; do not assume based on ABG values alone.
• Do not use this code if only a single primary acid-base disorder with appropriate compensation is present.
• Sequence this code after the underlying cause of the acid-base disturbance, if known and documented.