Pulmonology Coding Alert

Question: Are 94620 and 94621 considered diagnostic tests? What is the difference between the two?

Indiana Subscriber

Answer: Both codes are for diagnostic pulmonary stress tests; the former is simple and the latter is complex. They are used to determine the pulmonary status of a patient who has displayed respiratory symptoms/ compromise (such as shortness of breath). Code 94620 (pulmonary stress testing; simple [e.g., prolonged exercise test for bronchospasm with pre- and post-spirometry]) describes simple pulmonary stress testing where the patients baseline spirometry is measured. Then, he or she is put through an exercise routine, such as walking on a treadmill until respiratory symptoms occur.

A second spirometry measurement is then taken. This determines whether the patients symptoms were induced by exercise. Code 94621 ( complex [including measurements of C02 production, O2 uptake, and electrocardiographic recordings]) measures cardiac and pulmonary functions. A patient would require this type of testing if the symptoms were not explained by the simple test (as being exercise-induced).