Stay on the Top of ICD 10 Diagnosis Codes

Does everyone have to switch to ICD-10? Actually, no. Only HIPAA-covered entities are required to make the change. Auto insurance and worker’s compensation are not HIPAA-covered entities, so they are not required to use ICD 10 codes although there are many forces encouraging them to do so.

Psychiatrists use the DSM codes, not the ICD codes. So they may or may not be changing as well. DSM4 update is do out about the same time as ICD-10 and there is a lot of expectation that the DSM4 will mirror ICD-10 but it is not guaranteed at this point.

Dentists will probably not switch the ICD-10 since they use the ADA codes. The good healthcare coding newsis it is quite possible you will need to use ICD-9 and ICD-10 together at least for a while. But ICD-9 will not be updated after next year and that's going to be a limited update. So you should never have to purchase both an ICD-9 and an ICD-10 book.

The Department of Health and Human Services has said they will update ICD-9 and ICD-10 as usual in 2012 and 2011. But in 2012, they will only be updated for new technologies or diseases. After that, ICD-9 will never be updated again. ICD-10 will be updated in 2013, again, only for new technologies and diseases.

So if you have to use both code sets at the same time, how do you tell an ICD-9 from ICD-10? ICD-10 all start with a letter. ICD-9s almost always start with a number. The only ICD-9s that start with a letter are the V, E and M medical codes.

ICD-9, M codes are the tumor morphology codes and they generally aren't used for medical billing. They are a capital M, three letters a slash and a number letter, another number. Because there is a slash in there and they are the only code with a slash, they're very easy to tell from any other code sets.

E codes and ICD-9 are a capital E then three numbers, a decimal point and possibly another number. In ICD-10, E-codes are a capital E, two alphanumeric characters, a decimal and zero to four more alphanumeric characters. So if there are three numbers before the decimal, it's an ICD-9. If there are two numbers or number and a letter besides the E, it's an ICD-10.

And ICD-9, V-codes are a capital V then two numbers and a decimal point and zero to two more numbers. In ICD-10, V-codes are some of your external causes of disease and injuries. They're like the old ICD-9, E-codes. But all ICD-10 V-codes are seven characters. So any code with less than seven characters is an ICD-9.

ICD-10 uses the word “and” to mean “and/or”. It uses brackets to enclose synonyms and parenthesis to enclose supplemental words that may or may not be present. There are any CNNOS codes just like ICD-9 but remember that just because they exist, that does not mean carriers will necessarily pay for them.

In ICD-9, V and E-codes were considered supplementary classifications. They were not actual tabular chapters. ICD-10 has made them actual tabular chapters.

As we've mentioned, the codes themselves are a bit different. ICD-10 can use up to six characters levels of specificity. The first character is always a letter. The second character is always a digit. The third character is either a digit or a letter.

Now some ICD-10s are only three characters but a lot like ICD-9 there are not many ICD 10 diagnosis codes that stop at that level of specificity. The third character based code is separated from the extensions by a decimal point just like ICD-9. But each ICD-10 code could have zero to three more codes to increase the code specificity.

The seventh character in ICD-10 is reserved for codes that apply to all codes in a category such as upper sort of care indicators. These are generally located in the box in the ICD-10 tabular listings just like they were in ICD-9. These could be letters or they could be numbers.

ICD-10 uses the term “sequelae” for late effects. And it includes it in these box terms. So there's no longer an entire section for late effects like there is in ICD-9.

Some codes use a lower case x placeholder which comes in to play for consistency when a code does not have a six character level of specificity. But there is a seventh character that applies to that category, our expert mentioned in a healthcare webinar.

There's a few other differences. So let's take a little closer look at the I10 entry in the ICD-10 book. ICD-10 includes category notes. In this case, essential hypertension is part of the category of hypertensive diseases. And those include codes I10 through I15.

The category itself, there is used additional codes to identify just like there are in ICD-9s and it lists the codes that you should code in addition to the hypertensive diseases. Under that, it lists codes that are excluded from hypertensive diseases.

If you look at the individual I10 entry, essential primary hypertension includes, high blood pressure, hypertension, arterial, benign, essential, malignant, primary, systematic. Under that, you have an “excludes one”. That's one of the differences between ICD-9 and ICD-10. ICD-9 only had one type of exclude code. ICD-10 has two.
“Exclude one” indicators are codes that should never under any circumstances be coded with each other. In this case, I10 essential hypertension should never be on the same claims as 010 to 011 or 013 to 016 which are the codes for hypertensive diseases complicating pregnancy.

Think of exclude one codes as the medically unlikely edits of ICD-10. Exclude two indicators means that the diagnosis is not included in hypertension. And if the patient has it, you need to code it separately as per healthcare guidelines. So if your patient has essential hypertension and hypertension of eye vessels, you would want to code both I10 and H35.0.

Just like ICD-9, you do not code signs and symptoms in ICD-10 if the definitive diagnosis has been established during that visit. If a definitive diagnosis cannot be established, then you would code the signs and symptoms. You never code rule out diagnosis in ICD-10 just like ICD-9.

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