Pulmonology Coding Alert

Hint: Identify symptoms and medication use for accurate reporting.

Asthma's very likely the most common condition your pulmonologist diagnoses, so it's vital to know the specifics of reporting this condition using ICD-10 codes before the Oct. 1, 2014 effective date.

Capture ICD-9 Codes Based on Etiology

When reporting a diagnosis of acute exacerbation of asthma using ICD-9 codes, you will have to focus on etiology of the condition to accurately report it. When your pulmonologist arrives at a diagnosis of acute exacerbation of asthma, you will have to start with 493 (Asthma).

Depending on the causative factor for the asthma, 493 will expand into the following four codes:

• 493.0 (Extrinsic asthma) -- You report this type when asthma is caused by allergens.
• 493.1 (Intrinsic asthma) -- You report this type when asthma is induced after exercise or due to chemicals such as cigarette smoke, medications and cleaning agents
• 493.8 (Other specified asthma)
• 493.9 (Asthma unspecified)

The codes 493.0, 493.1 and 493.9 further expand using a fifth digit depending on the asthma state into unspecified, status asthamaticus and acute exacerbation.

For example, 493.0 expands into the following three codes:

• 493.00 -- Extrinsic asthma unspecified
• 493.01 -- Extrinsic asthma with status asthmaticus
• 493.02 -- Extrinsic asthma with (acute) exacerbation

493.8 expands into these two codes:

• 493.81 -- Exercise-induced bronchospasm
• 493.82 -- Cough variant asthma

Base ICD-10 Reporting on Severity of the Condition

When ICD-10 codes come into effect, 493 under ICD-9 codes will crosswalk to J45 (Asthma). But, unlike ICD-9 codes, your ICD-10 coding is not centered over the etiology of the condition but follows the severity of the symptoms and the necessity for treatment with a nebulizer.

Based on severity, you have the following four states of the condition (see chart for details):

• Mild intermittent
• Mild persistent
• Moderate Persistent
• Severe Persistent

When using ICD-10 codes, you will have to delve into the documentation to assess the severity of the condition as this is necessary for accurate reporting. J45 will further expand, based on severity, into the following five code sets:

• J45.2 (Mild intermittent asthma)
• J45.3 (Mild persistent asthma)
• J45.4 (Moderate persistent asthma)
• J45.5 (Severe persistent asthma)
• J45.9 (Other and unspecified asthma)

All these above mentioned codes further expand based on the asthma state into uncomplicated, acute exacerbation and status asthamaticus.

For example, J45.2 expands into the following three subsets:

• J45.20 (Mild intermittent asthma, uncomplicated)
• J45.21 (Mild intermittent
• J45.22 (Mild intermittent asthma with status asthmaticus)

J45.9 expands into the following code sets:

• J45.90 (Unspecified asthma) that further expands to J 45.901, J45.902, J45.909
• J45.99 (Other asthma) that further expands into J45.990 (Exercise-induced bronchospasm); J45.991 (Cough variant asthma) and J45.998 (Other asthma)

Example: Your pulmonologist assesses a patient with asthma who is currently experiencing episodes of acute exacerbation. Your pulmonologist records a detailed history that reveals that the patient has been suffering from symptoms for more than two times a week. His use of the inhaler is also more than two times a week although he does not have to use it on a daily basis. The acute exacerbation of symptoms has been limiting his daily activities to a certain extent. Your pulmonologist orders some pulmonary function tests. He records a forced expiratory volume in 1 second (FEV1) >80%. Based on the symptoms and results of tests, you can infer that the patient is suffering from acute exacerbation of a mildly persistent type of asthma. You report the diagnosis using J45.31 (Mild persistent asthma with [acute] exacerbation).

Source: (National Heart, Lung, and Blood Institute. Accessed: September 12, 2012. Expert Panel Report 3 (EPR3): Guidelines for the Diagnosis and Management of Asthma. URL: www.nhlbi.nih.gov/guidelines/asthma/asthgdln.htm).