Pulmonology Coding Alert

Ensure the presence of a physician when conducting these tests.

If you find it hard to differentiate between the two codes for pulmonary stress test, the key is to look out for clues in their descriptions.

A physician orders pulmonary stress testing on patients who complain of shortness of breath. The test allows the physician to determine if the underlying cause is heart disease or lung disease. If you'd have to code this test, you have two codes to choose from:

• 94620 -- Pulmonary stress testing; simple [e.g., six-minute walk test, prolonged exercise test for bronchospasm with pre- and post-spirometry and oximetry]
• 94621 -- Pulmonary stress testing; complex (including measurements of CO2 production, O2 uptake, and electrocardiographic recordings).

'Simple' and 'Complex' Splits the Difference

When you're coding 94620 and 94621, you would find that the words 'simple' and 'complex' differentiate one from the other. However, these words aren't enough to look forhints. You could differentiate 94620 from 94621 more easily if you understood what the descriptors imply in detail. For instance, if documentation supports it, most six-minute walk tests can be coded as 94620 - a test performed for pulmonary assessment.

"CPT Assistant indicates documentation should include heart rate, blood pressure, oxygen saturation, and liter flow of supplemental oxygen. Each of these should be recorded at rest, during exercise, and during recovery," says Jill M. Young, CPC, CEDC, CIMC, Young Medical Consulting, LLC in Michigan.

CPT 94620 also includes physician analysis of data, interpretation of the test, and a written report, she adds.

Important: Make sure the test is performed with the correct level of physician supervision and that the supervision is properly documented. CPT 94620 requires general supervision (available by phone or beeper) whereas 94621 requires direct supervision. 'Direct supervision' means the physician must be present in the office suite and immediately available to provide assistance and direction throughout the time the aide is performing services, according to CMS.

Example: A 70-year-old patient with COPD presents for evaluation for entrance into a pulmonary rehab program. Under direct supervision of a physician, she undergoes a sixminute walk test to evaluate distance, dyspnea, oxyhemoglobin desaturation, and heart rate. The physician repeats the test after a rest period to eliminate learning bias, but reported as one test. You would report this service with 94620.

94621 Constitutes a Series of Metabolic Test

CPT 94621 involves measuring the integration of cardiac and pulmonary function, and the status of physical fitness.This includes measuring CO2 production, O2 uptake, and electrocardiographic recordings of the patient's response to the stress.

What happens next: After completion of the complex pulmonary test, the physician reviews and interprets the results of these series of metabolic test. He includes the findings in a detailed report for supportive documentation.

Tip: Most medium-to-large sized hospitals and clinics have expensive equipment to use in complex pulmonary stress test. Pulmonologists who do not have access to the specialized equipment are likely to perform the simple test, and interpret the results without analysis of the additional measurements.

Example: A pulmonologist decides to order a complex pulmonary stress test for a 73-year-old patient who is found to have dyspnea which interferes with her ability to work and exercise. The test aims to pinpoint the cause of the dyspnea. The test measures the integration of cardiac and pulmonary function and the status of the patient's physical fitness. The CO2 production, O2 uptake, and electrocardiographic monitoring were also measured. Using the results of the complex metabolic tests, the physician analyzes and interprets the data, being able to calculate a dyspnea index, an anaerobic threshold, and O2 consumption. Then the physician prepares a written report of the test results. In this case, you should report the service with 94621.