An article published in the American Journal of Hypertension earlier this year found a rising trend in hospitalization for hypertensive emergency with reduction in hospital mortality during the last decade. Patients with acute cardiorespiratory failure, chest pain, stroke, acute chest pain, or aortic dissection were at the most risk of higher hospital mortality among other complications. Medical coding companies are well aware that correct coding of hypertensive emergency is crucial to track patients that require immediate treatment for the condition. In fact, in 2017, ICD-10 category 116 provides specific codes for hypertensive urgency and emergency, and both conditions are considered hypertension crises:
I16.0 hypertensive urgency
116.1 hypertensive emergency
I16.9 hypertensive crisis, unspecified
With the introduction of these new codes, accurate coding depends on knowing what comprises an urgent versus an emergent case of hypertension:
- Hypertensive crisis: Mayo Clinic’s definition of a hypertensive crisis is: A severe increase in blood pressure that can lead to a stroke. Extremely high blood pressure — a top number (systolic pressure) of 180 millimeters of mercury (mm Hg) or higher or a bottom number (diastolic pressure) of 120 mm Hg or higher — can damage blood vessels. The blood vessels become inflamed and may leak fluid or blood. As a result, the heart may not be able to pump blood effectively.Causes of a hypertensive crisis include noncompliance with blood pressure medication, stroke, heart attack, heart failure, kidney failure, rupture of the aorta, interaction between medications, and eclampsia. Patients presenting with hypertensive crisis need to be evaluated immediately to assess the organ function and rule out/in any organ damage and then determine the appropriate treatment.
Hypertensive crisis can be either urgent or emergent:
- Urgent: Systolic blood pressure is greater than 180 or a diastolic pressure greater than 110, without associated progressive organ dysfunction. Symptoms may include severe headache, shortness of breath, nosebleeds, or severe anxiety. The condition calls for immediate evaluation of organ function to determine appropriate treatment.
- Emergent: Blood pressure usually reaches high levels, exceeding 180 systolic and 120 dystolic, signifying impending or progressive organ damage. However, systolic and dystolic levels could be lower in patients without previous high blood pressure. The patient is at risk for stroke, loss of consciousness, memory loss, acute myocardial infarction or angina, aortic dissection, damage to the eyes and kidneys, and pulmonary edema. In pregnant patients, a hypertensive emergency could lead to eclampsia. In children, systolic blood pressure greater than the 99th percentile for age and sex, and symptoms such as headache (urgent) or seizure (emergent) are indicative of hypertensive urgency and emergency.
Note: When the clinical documentation supports a code from the category I16, Hypertensive crisis, the sequencing of codes is based on the circumstances of admission/reason for the admission/encounter. Any identified hypertensive disease (I10-I15) should also be coded.
In addition to coding for hypertensive crisis, there are significant changes when coding for hypertension regarding “with” documentation as well as revised heart disease guidelines and additional instructions for chronic kidney disease documentation.
CMS states: “The 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. For hypertension and conditions not specifically linked by relational terms such as “with,” “associated with” or “due to” in the classification, provider documentation must link the conditions in order to code them as related.”
- Hypertension with Heart Disease: Hypertension with heart conditions classified to I50.- or I51.4- I51.9, should be assigned to a code from category I11, Hypertensive heart disease. An additional code from category I50, Heart failure, should be reported to identify the type of heart failure in those patients with heart failure.If the provider has specifically documented a different cause, the same heart conditions (I50.-, I51.4-I51.9) with hypertension are coded separately. These should be sequenced according to the circumstances of the admission/encounter.
- Hypertensive Chronic Kidney Disease: Codes from category I12, Hypertensive chronic kidney disease, should be assigned when both hypertension and a condition classifiable to category N18, Chronic kidney disease (CKD), are present. CKD should not be coded as hypertensive if the physician has specifically documented a different cause.The appropriate code from category N18 should be used as a secondary code with a code from category I12 to identify the stage of chronic kidney disease.
If a patient has hypertensive chronic kidney disease and acute renal failure, an additional code for the acute renal failure is required.
- Hypertensive Heart and Chronic Kidney Disease: The codes in category I13, Hypertensive heart and chronic kidney disease, are combination codes that include hypertension, heart disease and chronic kidney disease, and should be used when there is hypertension with both heart and kidney involvement.
If heart failure is present, an additional code from category I50 should be reported to identify the type of heart failure.The appropriate code from category N18, Chronic kidney disease, should be used as a secondary code with a code from category I13 to classify the stage of chronic kidney disease.
The report in the American Journal of Hypertension notes that hypertension is the most common problem in primary care, and is the main modifiable risk factor when it comes to prevention of myocardial infarction, stroke, and renal failure. As providers focus on the management of hypertensive emergencies, medical coding service providers can ensure accurate reporting of the condition to meet CMS guidelines.