Part B Insider (Multispecialty) Coding Alert

Tip:  A standard pH test only requires one code

You can ease many of your coding headaches if you remember that diagnostic tests for gastroesophageal reflux disease (GERD) usually include pH monitoring. That's your clue to the codes you will report.

Do this: When your gastroenterologist provides an esophageal acid reflux test using either a disposable or a reusable nasal catheter, you should report 91034 (Esophagus, gastro-esophageal reflux test; with nasal catheter pH electrode[s] placement, recording, analysis and interpretation), says Linda Parks, MA, CPC, CMC, CMSCS, an independent coding consultant in Lawrenceville, GA.

In most cases, the physician will leave the catheter in place for about a day, but you will claim 91034 (without a "reduced service" or "unusual service" modifier) regardless of how long the catheter remains in place. This differs from past practice, in which you had to distinguish between standard and "extended" pH monitoring.

Example: For pH testing lasting six hours using a nasal catheter, you would report 91034. If the physician leaves the catheter in place for 26 hours, the coding is the same.

Another example: If your gastroenterologist conducts pH testing using a Bravo capsule, you'll turn to 91035 (Esophagus, gastroesophageal reflux test; with mucosal attached telemetry pH electrode placement, recording, analysis and interpretation) instead of 91034. The Bravo capsule has advantages over a standard catheter pH study, which can include greater patient comfort and the ability to monitor pH levels over a longer time period.

Generally, the gastroenterologist will place the capsule using an endoscope, which you may report separately in some circumstances.

If your gastroenterologist performs manometry and pH study for the same patient, you may report the procedures separately and expect separate reimbursement, even if the tests occur on the same date of service, Parks says. You shouldn't need to report any modifiers to separate the services.

Another way to distinguish multiple tests: As an alternative to billing manometry and pH study on the same day, you may report the manometry on the first day and use the date of service for the pH study as the day the test is completed (in other words, you will place the probe for the pH study on the same day as the manometry, but you will report the pH study on the next day of service, after the 24-hour monitoring has concluded).