Pulmonology Coding Alert

Question: We have started performing plethysmography tests recently. However, the insurance company lately has denied us some claims for this service. Where are we going wrong?

California Subscriber

Answer: Make sure that you are reporting 94726 (Plethysmography for determination of lung volumes and, when performed, airway resistance) correctly with the right modifiers if needed.

Code 94726 describes a diagnostic pulmonary evaluation where the provider performs a pulmonary function test, or PFT, to determine the patient’s lung volumes, such as total lung capacity, residual volume, and functional residual capacity. The testing also may include checking airway resistance. Report the encounter as following when:

1. The physician performs the interpretation only: when the physician is providing only the interpretation of the test that is performed on equipment owned by an independent facility, then the physician should bill 94726 with modifier 26 (Professional component) to represent the professional component of the service.

2. The physician supplies the equipment and technician, and the service is being provided in a non-facility setting (e.g., Place of Service 11 - Office): you do not append a professional or technical modifier to the code when reporting a global service in which the provider renders both the professional and technical components. So, you will report just 94726.

Verify that you are not billing plethysmography with gas dilution code 94727 (Gas dilution or washout for determination of lung volumes and, when performed, distribution of ventilation and closing volumes) or oscillometry code 97428 (Airway resistance by impulse oscillometry).