Late metabolic acidosis of newborn

This code signifies a metabolic acidosis that develops in a newborn after the immediate postnatal period, typically characterized by a low blood pH and bicarbonate levels. It indicates an imbalance in the body's acid-base regulation, occurring days or weeks after birth, rather than immediately following delivery.

Apply this code when documentation specifies metabolic acidosis in a neonate that is not present at birth but manifests later. This often includes cases related to renal tubular acidosis, organic acidemias, or other delayed metabolic derangements. Documentation should clearly state the onset of acidosis is "late" or specify a timeframe beyond the immediate neonatal period.

• Distinguish from congenital or immediate postnatal acidosis, which would be coded differently.
• Ensure documentation specifies "late" onset or a clear timeframe after birth to support this code.
• Always code the underlying cause of the late metabolic acidosis, if known, as a primary or secondary diagnosis.