Hypernatremia of newborn

This code identifies an elevated sodium concentration in the blood of a newborn infant, exceeding the normal physiological range. It indicates a state of dehydration or impaired water balance specific to the neonatal period.

Assign this code when documentation confirms a newborn (up to 28 days of age) presents with laboratory-confirmed hypernatremia. This typically occurs in cases of inadequate fluid intake, excessive insensible water loss, or iatrogenic causes.

• Ensure the patient's age is explicitly documented as a newborn.
• Distinguish from hypernatremia in older infants or adults, which would use different codes.
• Code any underlying cause of the hypernatremia, such as dehydration (E86.0), as an additional diagnosis.