ICD-10 Planning Your Route Before Your Journey

Published in Coding Edge – May 2007
By Deborah Grider, CPC, CPC-H, CPC-I, CPC-P, CEMC, CPMA, COBGC, CPCD, CCS-P
This month’s focus is “Understanding the ICD-10-CM draft guidelines for Diseases of the Circulatory System,” in relation to hypertension. Codes in this classification are organized in categories I10-I15 in Chapter 9 of ICD-10-CM.
According to the instructional notes for hypertensive disease, use an additional code when the patient has:

History of tobacco use (Z86.43)
Exposure to environmental tobacco smoke (Z58.83)
Occupational exposure to environmental tobacco smoke (Z57.31)
Tobacco dependence (F17.-) or Tobacco use (Z72.0)

This category also excludes hypertensive disease complicating pregnancy, childbirth and the puerperium, neonatal hypertension, and pulmonary hypertension.
Category I10 would be reported when the diagnostic statement indicates the hypertension is under control or uncontrolled with therapy.
Elevated blood pressure without further specificity is not coded in this category; it is assigned to R03.0. Code R03.0 may also be used for a single elevated blood pressure reading or for transient elevated blood pressure.
Example:
A patient visits his internist for his 3-month follow-up visit. He has been treated for hypertension for more than three years. The patient’s current blood pressure is 150/100 mm Hg. The patient is a smoker, although not dependent on tobacco. The physician adjusts the patient’s medication, reviews previous blood pressure readings, counsels the patient regarding smoking sessation, and asks the patient to follow up in two months. The documentation indicates benign hypertension without satisfactory control.
Review the comparison between ICD-9-CM and ICD-10-CM below:

ICD-9-CM

ICD-10-CM

401 Essential Hypertension

401.0 Essential hypertension, malignant

401.1 Essential hypertension, benign

401.9 Unspecified essential hypertension

I10 Essential (Primary) HypertensionIncludeshigh blood pressurebenign
arterial
essential
malignant
primary
systemic in this category

ICD-9-CM	ICD-10-CM
401.1 Essential hypertension, benign	I10 Essential (primary) hypertensionZ72.0 Tobacco use

With category I10 an additional code is reported for tobacco exposure, dependence, or use, which differs from the guidelines in ICD-9-CM.
There is an excludes 2 note indicating that hypertension (I10) may be reported in addition to the following:

Essential (primary) hypertension involving vessels of brain (I60-I69)
Essential (primary) hypertension involving vessels of eye (H35.0)

Category H35.0 is reported for hypertensive retinopathy and may be used alone or with I10. If both codes are used, the sequencing is based on the reason for the encounter.
Example: A patient presents to the ophthalmologist for follow up of hypertensive retinopathy. The physician determines the retinopathy is due to the patient’s malignant hypertension.

ICD-9-CM	ICD-10-CM
362.11 Hypertensive retinopathy	H35.033 Hypertensive retinopathy, bilateralI10 Essential (primary) hypertension

In ICD-9-CM, the hypertension is not reported. There is an instructional note with 401.x that excludes hypertension with the eye (362.11). In ICD-10-CM the excludes 2 note allows the reporting of both codes.
Hypertensive Heart Disease
Hypertensive heart disease is classifed to category I11. Hypertensive heart disease diagnoses are combination codes that include both the hypetension and the heart disease. There is an includes note that indicates the conditions included with hypertension in category I11. A causal relationship does not need to be documented. For hypertension with heart failure, a secondary code is required from category I50 to identify the type of heart failure.
Review Category I11
I11 Hypertensive heart disease
Includes: any condition in I51.4-I51.9 with hypertension
I11.0 Hypertensive heart disease with heart failure

Any condition in I50.- with hypertension Hypertensive heart failure

Use additional code to identify type of heart failure (I50.-)

I11.9 Hypertensive heart disease without heart failure

Hypertensive heart disease NOS

Example:
A cardiologist treats an established patient for hypertensive heart disease with benign hypertension. The patient is doing well and after a detailed history and examination, the physician determines the current regimen is effective and in six weeks will follow up with the patient.
Codes reported

ICD-9-CM	ICD-10-CM
402.10 Benign hypertensive heart disease without heart failure	I11.9 Hypertensive heart disease without failure

Rationale: Since the practitioner did not identify heart failure in the documentation, only one code is reported for ICD-9-CM and ICD-10-CM.
Hypertensive Renal Disease
Hypertensive renal disease requires combination codes that include hypertension and renal disease coded in category I12. There is an includes note specifying the conditions included in this category. If a patient has both a condition listed in the includes note and hypertension, the combination code category I12 is reported, and not individual codes for hypertensive renal disease. If a patient has hypertension with both acute and chronic renal failure, an additional code for the acute renal failure is required.
I12 Hypertensive renal disease
Includes: any condition in N18.-with any condition in I10 arteriosclerosis of kidney arteriosclerotic nephritis (chronic) (interstitial) hypertensive nephropathy nephrosclerosis

Excludes1: renovascular hypertension (I15.0) secondary hypertension (I15.-)

Excludes2: acute renal failure (N17.-)

I12.0 Hypertensive renal disease with chronic renal failure

Any condition in N18.- with hypertension Hypertensive renal failure

I12.9 Hypertensive renal disease without renal failure

Hypertensive renal disease NOS

Example:
A patient with malignant hypertension and stage 4 chronic renal disease is admitted to the critical care unit. The patient is in acute renal failure with acute cortical necrosis.

ICD-9-CM	ICD-10-CM
403.00 Hypertensive chronic kidney disease, malignant, with chronic kidney disease stage I through stage IV, or unspecified585.4 Chronic kidney disease, Stage IV (severe)584.6 Acute renal failure with lesion of renal cortical necrosis	I12.0 Hypertensive renal diseasewith chronic renal failureN17.0 Acute renal failure with acute cortical necrosis

In ICD-9-CM the stage of the chronic kidney disease is reported. No codes to identify the stage of chronic kidney disease have been developed for ICD-10-CM.
ICD-10-CM Coding Tip: Remember to code the acute renal failure when the patient is diagnosed with both acute and chronic renal failure.
ICD-10-CM Update: Former speaker of the House Newt Gingrich founded the group The Center For Health Transformation, which recently released the white paper Health Action for the 110th Congress; Setting the Right Course to Transform Health. The group recommends that Congress allows the Department of Health and Human Services (HHS) to move to ICD-10-CM coding within a reasonable time frame to ensure that technology is capturing and reporting accurate information.