Primary Care Coding Alert

How well do you know the I10-I16 codes and guidelines?

Once you’ve answered the quiz questions on page 3, compare your answers with the ones provided below:

Answer 1: In this scenario, you cannot code for hypertension. That’s because “you can only code for hypertension when the physician specifically diagnoses it,” says Marcella Bucknam, CPC, CCS-P, COC, CCS, CPC-P, CPC-I, CCC, COBGC, revenue cycle analyst with Klickitat Valley Health in Goldendale, Washington.

In this case, “the patient has his/her blood pressure taken under reliable circumstances — in this scenario by the home health nurse — and actual hypertension is not present,” Bucknam believes. This suggests the provider has observed a case of white coat hypertension, where the patient’s blood pressure is elevated during office visits but not outside the clinical setting.

Consequently, you would use a code such as R03.0 (Elevated blood-pressure reading, without diagnosis of hypertension) rather than I10 (Essential (primary) hypertension) for this particular scenario, though this is an occasion “where a discussion will have to take place between the provider and coder to determine the exact diagnosis to code,” says Donelle Holle, RN, president of Peds Coding Inc., and a healthcare, coding, and reimbursement consultant in Fort Wayne, Indiana.

Answer 2: A brief glance at ICD-10 guideline I.C.9.a.1 will help you arrive at the correct answer to this scenario. The guideline states, in part, that “hypertension with heart conditions classified to I50.- [Heart failure] or I51.4 [Myocarditis, unspecified]?I51.7 [Cardiomegaly], I51.89 [Other ill-defined heart diseases], [or] I51.9 [Heart disease, unspecified], are assigned to a code from category I11, Hypertensive heart disease. Use additional code(s) from category I50, Heart failure, to identify the type(s) of heart failure in those patients with heart failure.”

Another guideline, I.C.9.a., tells you why. Hypertension “classification presumes a causal relationship between hypertension and heart involvement and between hypertension and kidney involvement, as the two conditions are linked by the term ‘with’ in the Alphabetic Index. These conditions should be coded as related even in the absence of provider documentation explicitly linking them, unless the documentation clearly states the conditions are unrelated.”

So, as hypertension has caused the patient’s heart failure, you would report I11.0 (Hypertensive heart disease with heart failure). But following the guidelines and the instructional note accompanying I11.-, which tells you to use an additional code from I50.- “to identify the type of heart failure,” you would use a code such as I50.1 (Left ventricular failure, unspecified) in addition to I11.0.

Coding alert: To sequence the codes, you need to follow the instructional “code first” notes that accompany the I50.- codes. These notes “indicate the primary reason for the diagnosis. They indicate the main cause for this other diagnosis and say, ‘this disease or illness has caused this other disease or illness,’” according to Holle. This means you would report I11.0 before I50.1 as the hypertension was the cause of the heart failure.

Answer 3: Opposite to scenario 2, in scenario 3 the hypertension isn’t causing the kidney condition, so it’s not the essential or primary condition in the patient’s diagnosis. Instead, the kidney disease is causing the hypertension, as the narrowing of the arteries that carry blood to the kidneys creates a rise in blood pressure.

Consequently, you will need to bypass I10 and go to the I15.- (Secondary hypertension) codes to find the correct code to use in this scenario. Here, you will find I15.0 (Renovascular hypertension), which is the precise code for the patient’s diagnosis.

A note under I15.- then directs you to code also the underlying condition, which makes sense as “code I15.- implies a situation where resolving the other condition would resolve the hypertension,” according to Bucknam. In fact, “there is an assumption in coding that almost all hypertension is renal in origin,” Bucknam explains.

This means you will use another code in this scenario, which is I70.1 (Atherosclerosis of renal artery). And, as this is the cause of the hypertension, I70.1 will be the first listed code.

Expert coding tip: Ultimately, to code hypertension correctly, you need “to be certain that you pick the correct hypertension code and decipher if the hypertension is the cause of a secondary disease, like heart disease, or vice versa. Again, this is where you have to have a discussion with your provider,” Holle concludes.

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