By Therese M. Jorwic, MPH, RHIA CCS, CCS-P, FAHIMA
The best way to begin ICD-10-CM training is to start at the beginning – what it is and where it comes from.
ICD stands for International Classification of Diseases. It is a worldwide coding system established by the World Health Organization.
The WHO is an arm of the United Nations that deals with international public health issues. It was established in 1948 and is headquartered in Geneva, Switzerland.
WHO studies and monitors areas of international public health and played a leading role in the eradication of smallpox. It uses the ICD codes to define dis-eases, study disease patterns, monitor outcomes of diseases, and allocate resources. More than 100 countries use the ICD to report mortality data.
The United States started using the ICD codes in the 1950s, and in recent years we have been clinically modifying the system, which means we have been expanding it to cover more distinct causes of diseases to correlate with the mortality causes. Thus, the system we use is known as ICD-9-CM, or the “Clinical Modifications” version. Our CM version does not change the basic code structure WHO sets out but simply adds subcategories and characters.
ICD-9-CM, which we use today, is the ninth revision of those codes. We have been using it since the mid 1970s, so it’s more than 30 years old – and ready for an update!
Enter ICD-10, which is the tenth revision. And surprisingly, it’s not that new. It was established in 1990 and has been in use in many countries since 1994.
What’s all this ICD-11 business?
ICD-10 isn’t the end of it all. Its successor, ICD-11 (or the 11th revision), is already being developed internationally and is due to be released in 2015.
Because we haven’t begun to use ICD-10 and also out of fear that moving to ICD-10 will create tremendous hardship to physicians and hospitals, some associations have recommended skipping ICD-10 altogether and picking up ICD-11 in 2015.
Don’t count on it.
Once ICD-11 is released, we will have to develop a clinically modified or CM version, and that will take at least five years, delaying our start date back to around 2020 – and that’s probably an early estimate.
What’s more, ICD-11 is based on ICD-10. Moving from 9 to 10 will be a natural progression, but jumping from 9 to 11 would be a tremendous challenge.
A good example of what to expect
Once everybody understands the origin and purpose of ICD-10, focus the training on how the two code sets differ and how they are similar.
A good example to use is diabetes, because that’s a diagnosis just about all offices encounter.
DIABETES AND ICD-9-CM
In ICD-9-CM, the category code for diabetes mellitus is 250.
Then there’s a fourth digit to show if there is a complication:
0 – without mention of complication
1 – ketoacidosis
2 – hyperosmolarity
3 – other coma
4 – renal manifestations
5 – ophthalmic manifestations
6 – neurological manifestations
7 – peripheral circulatory disorders
8 – other specified manifestations
9 – unspecified complication
The first three – ketoacidosis, hyperosmolarity (an excessive amount of glucose), and other (maybe hyperglycemia where there is an insufficient amount of sugar) – are primary or current complications of the diabetes itself. The others are secondary, or complications that occur elsewhere in the body as a result of the diabetes. When a secondary condition is present, there needs to be another code telling what it is.
Then there’s a required fifth digit to show the type of diabetes and whether it is controlled or uncontrolled:
0 – type II (unspecified), not stated as uncontrolle
1 – type I (juvenile), not stated as uncontrolled
2 – type II (unspecified), uncontrolled
3 – type I (juvenile), uncontrolled
Thus, the diabetes mellitus code always has five digits. And if there is a secondary complication, there’s another code as well.
So suppose the patient has type II diabetes with secondary complications of mild nonproliferative retinopathy and macular edema.
The first code will be 250.50 (250 = diabetes, 5 = ophthalmic manifestation, 0 = not uncontrolled).
And following that are two more codes:
326.04 (mild nonproliferative retinopathy) and 362.07 (macular edema).
Thus, we currently need three codes for that single situation.
DIABETES AND ICD-10-CM
Diabetes well illustrates a great feature of ICD-10-CM, which is a beautiful thing called combination codes. There’s one combination code that tells all the things it just took three codes to describe in ICD-9-CM.
In ICD-10-CM, the category code for type II diabetes is E11 (for type I, it’s E10).
Then there’s a fourth character for the complication:
0 – hyperosmolarity
2 – kidney complications
3 – ophthalmic complications
4 – neurological complications
5 – circulatory complications
6 – other specified complications
8 – unspecified complications
9 – without complications
For this patient, the complications are ophthalmic,
so the fourth character is 3. And under that are several
options:
1 – unspecified diabetic retinopathy
2 – mild nonproliferative diabetic retinopathy
3 – moderate nonproliferative diabetic retinopathy
4 – severe nonproliferative diabetic retinopathy
5 – proliferative diabetic retinopathy
6 – diabetic cataract
9 – other diabetic ophthalmic complication
Our patient has mild nonproliferative retinopathy, which is 2, and under that are two more options:
1 – with macular edema
2 – without macular edema
So the complete code is E11.321 (E11 = type II diabetes, 3 = with ophthalmic condition, 2 = mild prolific diabetic retinopathy, 1 = with macular edema).
All those factors are found in the same spot. There’s no turning pages from one area to another.
Similar guidlines, more details
Everybody also needs to understand how the two systems compare. Here are three points:
Similar guidelines: For the most part, ICD-10-CM follows the same coding guidelines as ICD-9-CM.
With diabetes, for example, current guidelines says that if the record doesn’t show if it’s type I or type II, assume it is type II. The new guides say the same.
Both also say that if the patient has type II diabetes and is on full-time insulin, there needs to be a separate code for the long-term insulin use.
And both say to use that extra code only if the insulin use is routine and not for temporary control.
More details: The ICD-10-CM codes show more detail than our current codes can show.
One especially useful detail is bilaterality, or left and right. With glaucoma, for example, the new codes show right eye, left eye, both eyes, and unspecified.
Currently, a few codes show bilaterality, but otherwise, left and right are just not codeable. If a patient had glaucoma in the right eye last year and now has it in the left eye, there’s no way to code the distinction.
Or suppose the patient has open angle pigmentary glaucoma, mild stage, in the right eye.
With ICD-9-CM, the code is 356.13. Then there’s an additional code (365.71) to identify the stage. And there’s no way at all to show that it’s the right eye.
With ICD-10-CM, however, one code shows the entire picture – H40.1311. (H40 = glaucoma, 1 = open angle, 3 = pigmentary, 4 = right eye, 1 = mild stage).
More chapters: ICD-9-CM has 17 chapters; ICD- 10-CM has 21.
The four extra chapters aren’t really new. Instead the old chapters have been reformatted to make things more distinct.
The first two new chapters are for diseases of the eye and ear, which currently are found in the chapter on the nervous system. In ICD-10-CM, they have their own chapters.
The other two new chapters are for the factors influencing health status (ICD-9-CM’s V codes) and external causes of injury (ICD-9-CM’s E codes). In ICD-9-CM those are supplementary chapters, but in ICD-10-CM they have their own chapters.
Therese M. Jorwic, MPH, RHIA, CCS, CCS-P, FAHIMA, is assistant professor of health information management at the University of Illinois at Chicago and senior consultant for MC Strategies in Atlanta.
She is also coauthor of ICD-10-PCS: An Applied Approach, published by AHIMA Press.
