Breathe Easy: Foolproof Fifth-Digit Coding for Asthma

If you're not reporting asthma ICD-9 codes to the highest level of specificity, your allergy practice is probably losing money. To avoid denials and receive the right reimbursement for your asthma patients, you should make certain you know how to use the fifth digits that ICD-9 2002 added to the asthma diagnosis codes.
Though the new asthma diagnosis codes have been in effect all year, many coders are still confused about how to use them.
The new 2002 diagnosis codes for asthma (493.0x, Extrinsic; 493.1x, Intrinsic; 493.9x, Unspecified) have five digits, with the fifth digit indicating stable (0), in status (1), or with acute exacerbation (2). The fifth digit clarifies the distinction between a stable patient and one with acute exacerbation.

ICD-9 2002 revised the description of the fifth-digit 0 for 493.x (Asthma) to read "without mention of status asthmaticus or acute exacerbation or unspecified." The definition previously read, "without mention of status asthmaticus."

"An asthma code's fourth digit indicates whether it is extrinsic, intrinsic, chronic obstructive or unspecified, while a fifth digit indicates the degree of the asthma," says Daniel Fick, MD, director of risk management and compliance for the College of Medicine faculty practice at the University of Iowa in Iowa City. "The revision to the fifth-digit 0 clarifies that the patient's asthma is not exacerbated."

Because most patients who come into the office for asthma treatment are experiencing exacerbation, using the 0 will be more unusual than using the fifth-digit 2, Fick says. Practices usually report the 0 when a patient comes in for a checkup for his asthma.
As an example of how fifth-digit asthma coding comes into play, suppose a patient who regularly uses an inhaler complains to the allergist that the inhaler is not relieving her asthma. The physician performs a peak-flow test, which measures 200 l/m instead of the normal 400 l/m. The doctor increases the patient's therapy.
In this case, you would report 493.12 (Intrinsic asthma; with acute exacerbation). The fourth-digit 1 shows that the asthma is intrinsic, while the fifth-digit 2 indicates that the patient had an acute exacerbation.
Fifth Digits Crucial for Nebulizer Treatment
The specificity that fifth digits provide is important for supporting the medical necessity of asthma treatments. "Coders should be coding to the most specific code versus using the generic code," especially when a nebulizer is involved, says Chrissy Rogan, CPC, billing coordinator for Metropolitan ENT in Alexandria, Va.

From a reimbursement standpoint, fifth-digit coding is important because a patient with acute exacerbation may require nebulizer treatments, while a stable patient will not. Without the fifth digit, a claim for nebulizer treatment (94640, Nonpressurized inhalation [...]

- Published on 2002-09-01