General Surgery Coding Alert

Question: Our surgeon frequently works with diabetic and stroke patients, and I understand the need to report underlying conditions. But, when should I use a diagnosis of malignant hypertension? If a patient has hypertension, should I report 401.0 or 401.1?

California Subscriber

Answer: Code 401.x (Essential hypertension) contains three fourth-digit sub-classifications. Because 401.0 (... malignant) describes a life-deteriorating disease, you will rarely use that code (and, unless the physician specifically documents the disease as malignant, you cannot assume that it is malignant).

With malignant hypertension, the patient's blood pressure rapidly and severely elevates. The high blood pressure causes severe damage that can result in organ failure and/or death if untreated. A patient in such debilitation would require hospitalization. Therefore, 401.0 normally applies to patients who are in an intensive care unit or an emergency room rather than rehab facilities, where your physician is probably seeing these patients.

By the same token, you should not assume that the patient's hypertension is benign (401.1), either.

Unless documentation specifically mentions "benign" or "malignant" (or you can receive and document this information from the treating physician), you should stick to 401.9 (... unspecified). But payers generally prefer more specific diagnoses, and you should question the attending physician to be sure a more exact diagnosis does not exist.