Pulmonology Coding Alert

Focus on the underlying condition for best results.

You can code correctly and efficiently for acidosis and alkalosis only when you know the reasons for pulmonologist’s treatment choices. This, in turn, is possible when you have sufficient knowledge about various conditions that cause them, and the differences between the two conditions. Our practical tips will guide you on how to link ICD-10 diagnosis codes to procedures and the underlying conditions in a real life situation. 

Acidosis Primer

Sometimes, excess carbon dioxide (CO2) collects in the blood of a patient, which usually is a classic presentation of respiratory acidosis. The excess CO2 causes a depletion of the blood’s pH level. The increased CO2 can be caused due to many reasons such as upper or lower airway obstruction, acute lung infections or inflammation, bronchial tissue infections and other acute or chronic lung conditions. The correct code for this condition ICD-9 is 276.2 (Acidosis). In ICD-10, the code will change to E87.2 (Acidosis).

You need to know the types of acidosis and its underlying conditions, so that you can follow your pulmonologist’s line of reasoning when he starts the treatment. Respiratory acidosis is classified into two types:

•  Acute— The condition has a chance of a sudden respiratory system collapse. For instance, the condition could be a result of respiratory depression due to an airway obstruction caused by asthma, which you will have to capture with ICD-10 code J45.--with fourth and fifth digits capturing the severity of the asthma. Currently you code 493.12 (Intrinsic asthma; with [acute] exacerbation). Asthma further branches out based on severity.
•  Chronic— A gradual and irreversible loss of ventilatory function, such as chronic obstructive pulmonary disease (COPD) may lead to this form. From next year, you will have to use J44.9 (Chronic obstructive pulmonary disease, unspecified) in place of 496 (Chronic airway obstruction, not elsewhere classified) to correctly code this condition.

Treat the Underlying Condition

When too little carbon dioxide raises the pH level in a patient’s blood, the patient may have respiratory alkalosis, which you currently code with 276.3. Respiratory conditions, such as pneumonia or acute asthma, can lead to alkalosis. The ICD-10 equivalent is E87.3 (Alkalosis).

Usually, when you report alkalosis, the accompanying symptoms are hyperventilation (786.01) and light-headedness (780.4). The physician’s treatment options involve treating the underlying condition. After the code changes, codes of these two symptoms will change to R06.4 (Hyperventilation) and R42 (Dizziness and giddiness) respectively.

ICD-10 Codes in Real-Life Coding Scenario

You may see many signs and symptoms that make your pulmonologist decide on an acidosis or alkalosis diagnosis, but you should bridge only the primary condition and the procedure codes. 

Case: A patient presents with severe asthma (493.12) and develops fever (780.60), wheezing (786.07) and fatigue (780.79). Tests confirm a diagnosis of acidosis (276.2). The physician inserts an endotracheal tube (31500, Intubation, endotracheal, emergency procedure) during treatment. 

Do it yourself: Although you can code J45.xx for the asthma, R50.9 for the fever, R06.2 for wheezing and R53.1 for general weakness, make sure to connect your procedure code (31500) to the underlying condition, J45.-- (asthma), and not E87.2 (acidosis), which is the secondary condition. You should use J45.-- because acidosis is the physician’s official diagnosis, whereas wheezing and fatigue are signs and symptoms.