ED Coding and Reimbursement Alert

Question: When reporting an asthma diagnosis, do I need a fifth digit?

North Carolina Subscriber
 
Answer: Yes. ICD-9 requires you to use a fifth-digit subclassification with asthma codes (493.xx). If you
submit four digits for an asthma diagnosis, payers will probably reject the ICD-9 code as incomplete.
 
The asthma category and current state drive the Dx choice.
 
Correct method: Assign the fourth digit based on the asthma category:

 - 493.0x -- Extrinsic asthma
 - 493.1x -- Intrinsic asthma
 - 493.2x -- Chronic obstructive asthma
 - 493.8x -- Other forms of asthma
 - 493.9x -- Asthma, unspecified.
 
Then, identify the asthma's current state with the appropriate fifth digit:
 - 0 -- unspecified
 - 1 -- with status asthmaticus
 - 2 -- with (acute) exacerbation. 
 
For patients who do not have status asthmaticus or acute exacerbation, use a fifth digit of -0.- Code 493.x0 is appropriate when the patient presents for a checkup and his asthma is controlled.
 
A final digit of -1- indicates that the patient has status asthmaticus, which is a medical emergency and is usually treated in the ED.
 
You should assign a -2- for patients who present with asthma that is now exacerbated (in other words, something has caused the condition to flare up).
 
Why it matters: Without this higher level of specificity, the payer may deny your claim for lack of medical necessity.

 -- Reader Questions and You Be the Coder reviewed by Michael A. Granovsky, MD, CPC, FACEP, vice president of Medical Reimbursement Systems Inc., an ED coding and billing company in Stoneham, Mass.