Hypertensive encephalopathy

This code signifies a severe, acute neurological dysfunction caused by malignant hypertension. It involves cerebral edema and microhemorrhages resulting from a sudden, significant increase in blood pressure that overwhelms the brain's autoregulatory capacity. Patients typically present with altered mental status, seizures, headaches, and visual disturbances.

Assign this code when documentation clearly indicates encephalopathy directly attributable to uncontrolled hypertension, often presenting as a hypertensive crisis. Look for physician notes detailing acute neurological symptoms alongside severely elevated blood pressure readings. This diagnosis requires a direct causal link between the hypertension and the brain dysfunction.

• Ensure documentation explicitly links the encephalopathy to hypertension; do not assume causation.
• Code the underlying hypertension first, followed by this code, as it represents a manifestation.
• Differentiate from other encephalopathies (e.g., toxic-metabolic, anoxic) where hypertension may be present but not the primary cause.