Coding arterial ulcers

When the supply of blood to an area of the body is not sufficient, the result is a shortage of oxygen and glucose needed for cellular metabolism.
The medical term for this condition is ischemia. The blood flow problem may be due to narrowing of the arteries by spasm or disease – or by some other form of arterial obstruction, such as pressure or trauma.
Some serious health risks, including stroke, are associated with insufficient blood supply, depending upon where in the body the blood flow is restricted.
When blood does not flow adequately to the capillary beds of the lower extremities, one of the most painful results may be an ischemic, or arterial, ulcer.
These ulcers typically present on the lower leg or foot, particularly on the sides of the foot or the tips of a patient’s toes, where there is inadequate perfusion of skin and subcutaneous tissue.
Clinicians generally recognize arterial ulcers by their “punched out” appearance. They are full thickness wounds with smooth edges.
The appearance of the ulcer with regard to shearing and stretching of the tissue, whether dead tissue is sloughing off or whether there is eschar, a black tissue that can create a hard shell over an ulcer, is important to properly code an arterial ulcer. This is because ICD-10 classification requires documentation of the severity of the ulcer, even in the absence of documentation from the physician. We’ll  take a look at the general stages of severity later in this article.

Causes and relationships
     It is also important to note the underlying condition when coding arterial ulcers. Circulation problems which lead to ischemic, or arterial, ulcers may be caused by conditions such as coronary disease, artery disease, diabetes mellitus, hypertension, hyperlipidemia, Peripheral Artery Disease (PAD) or smoking.
The prevalence of arterial insufficiency ulcers among people with diabetes is particularly high due to decreased blood flow caused by the thinning of arteries. A lack of sensation due to diabetic neuropathy may also contribute.

New coding guidance
Home health coders are well aware of the link between diabetes and narrowing of the arteries, and are used to combing medical records for specific documentation by the physician of the cause and effect.
New coding guidance, however, has impacted the need for specific links such as “due to” in notes from the physician regarding the diagnosis of a diabetes-related condition which results in certain circulatory complications.
The guidance change has left many home health coders feeling wary and uncertain as they tread this new ground. Online coding forums are filled with questions about the need to link arterial flow conditions such as Peripheral Vascular Disease with a diagnosis of Diabetes Mellitus.
Based on new AHA Coding Clinic guidance for the linkage between DM and certain conditions, some arterial conditions causing blood flow restrictions in patients who also have a diagnosis of DM may now be assumed to be linked to the diabetes —  even without specific documentation from the physician.
       The ICD-10 classification assumes the link in ICD-10 coding manuals wherever it lists subterm conditions indented beneath the word “with” alongside a diagnosis such as diabetes mellitus.
Note that two other requirements must also be met:
1. There must be documentation by the physician of both the diagnosis AND the condition
2. There must be no other reason provided for the condition

For example, the physician may not have directly attributed a patient’s peripheral angiopathy without gangrene to diabetes, but if there is a diagnosis of Type 2 DM and documentation of the patient’s peripheral angiopathy, you would select the code E11.51 for Type 2 DM with diabetic peripheral angiopathy without gangrene.

Coding arterial ulcers
As with everything coded in ICD-10, great specificity is required when coding arterial ulcers and the diagnoses and conditions associated with them.
Coders will need to use additional codes to identify specific ulcers. Laterality MUST be documented. Even the severity of the ulcer must be noted.
Avoid using unspecified codes if at all possible. Code to the highest level of specificity. The new coding guidance referenced above actually makes this level of specificity easier to achieve in many instances because the ICD-10 classification set assumes some of the burden of properly linking diagnoses and conditions, and allows the selection of a code establishing the underlying condition as well as its manifestation.
It is critically important for coders to remain diligent in carefully reading and following all guidelines as they code arterial ulcers and associated conditions.
As always, proceed very carefully with attention to the directions provided in the classification set itself. Pay very close attention to details such as Excludes 1 and Excludes 2 notes, and requirements to use additional codes. Make sure to document underlying diseases as appropriate.

Diagnoses, conditions and codes

Here are some of the diagnoses and conditions home health coders will encounter when coding an arterial ulcer, along with helpful coding notes.ARTHEROSCLEROSIS:
Atherosclerosis, also known as arteriosclerosis, is a widespread accumulation of fatty deposits in the arteries that may reduce blood flow to the legs, heart or brain. It can lead to Peripheral Arterial Disease or Peripheral Vascular Disease.
Atherosclerosis of the extremities is classified in ICD-10 to Code I70.2-
A fifth digit will be required when coding atherosclerosis and will indicate complications associated with atherosclerosis, such as intermittent claudication (which is pain while walking that resolves when resting), ulceration and gangrene.
A sixth digit will also be required to fully describe the location, such as right leg, left leg, bilateral legs, or other and unspecified extremity.)
As noted above, these codes have many Excludes 1 and Excludes 2 notes, as well as requirements to use additional codes, so care must be exercised to code correctly.PERIPHERAL ARTERIAL DISEASE (PAD):
Typically, the primary diagnosis for a patient who has an arterial ulcer will be Peripheral Arterial Disease, or PAD.  This is a circulatory in which blood cannot move freely through the patient’s arteries due to narrowing or other restriction. The occurrence of an arterial ulcer is a risk factor for PAD.
The most common symptom associated with PAD is intermittent claudication (pain while walking, that resolves after a few minutes of rest.) The location of the pain will depend on the site of the narrowed or clogged artery.PERIPHERAL VASCULAR DISEASE (PVD)
As with PAD, this diagnosis indicates narrowed or clogged blood vessels that restrict blood flow. Typically, a patient has PVD as a result of artherosclerosis.PAD, PVD and intermittent claudication, not otherwise specified, are classified to ICD-10-CM code I73.9, which also includes peripheral angiopathy, not otherwise specified, and spasm of artery.

This disease is common among heavy smokers, diabetics and the elderly. It can lead to claudication, pain at rest and gangrene, in addition to localized ulceration. Pain while walking is the most common presenting complaint and can indicate intermittent claudication.

Determining the severity of an ulcer

One of the ways in which ICD-10 differs from ICD-9 is that is requires clinicians to determine, in the absence of physician documentation, the SEVERITY of an arterial ulcer.
While WOCN has not yet released specific guidance for the determination of the severity of these ulcers, the general levels of severity are considered to be as follows:

— The ulcer is limited to the breakdown of the skin. There may be an abrasion blister and partial skin loss involving the epidermis and/or dermis.

— The fat layer (or subcutaneous tissue) is exposed.

— There is necrosis of the muscle (associated with break in or loss of muscle surface fiber membrane, which results in irreversible damage to the whole, or a segment of, muscle fiber)

— There is necrosis of bone (death of the bone by ischemia, infection, malignancy)

— Unspecified severity