Pathology/Lab Coding Alert

Change involves code additions and deletions.

If your lab/pathologist is involved in anticoagulation management, you have two new and two deleted codes in CPT^® 2018 that you'll need to know.

In addition to the CPT^® code changes, you need to remember lab test codes and other related HCPCS Level II codes that you may use for Medicare beneficiaries. Read on to get the lowdown on revisions to coding these services.

These are Out

CPT^® 2018 deletes the following two codes that described anticoagulant management services:

• 99363 (Anticoagulant management for an outpatient taking warfarin, physician review and interpretation of International Normalized Ratio (INR) testing, patient instructions, dosage adjustment (as needed), and ordering of additional » tests; initial 90 days of therapy (must include a minimum of 8 INR measurements))
• 99364 (... each subsequent 90 days of therapy (must include a minimum of 3 INR measurements)).

These deleted codes were in the E/M section and focused on the treatment duration - 90 days of anticoagulant management - as opposed to the specific tasks the physician or other qualified health care professional performed. As such, surgeons often found that using these codes was not appropriate, even when they had to monitor patient anticoagulant therapy during the surgical global period.

These are In

CPT^® 2018 adds the following new codes:

• 93792 (Patient/caregiver training for initiation of home international normalized ratio [INR] monitoring under the direction of a physician or other qualified health care professional ...)
• 93793 (Anticoagulant management for a patient taking warfarin, must include review and interpretation of a new home, office, or lab international normalized ratio (INR) test result, patient instructions, dosage adjustment (as needed), and scheduling of additional test(s), when performed).

Opportunity: You can see that the new codes focus on the actual services provided, rather than on the 90-day monitoring period. Also note that these codes are in the medicine section, and they might be separately billable when pathologists perform these services as part of patient management in a setting such as a Coumadin clinic.

"This change helps to better understand the type of service that is being provided," according to Suzan Hauptman, MPM, CPC, CEMC, CEDC AAPC fellow, senior principal of ACE Med Group in Pittsburgh. "Checking a patient's lab results around their INR and adjusting the medication may not require a face-to-face service or the attention of the physician; both two components of most all E/M services."

Remember Medicare Options

For similar services for Medicare beneficiaries, remember that you have the following three existing codes to choose from:

• G0248 (Demonstration, prior to initiation of home INR monitoring, for patient with either mechanical heart valve[s], chronic atrial fibrillation, or venous thromboembolism who meets Medicare coverage criteria, under the direction of a physician; includes: face-to-face demonstration of use and care of the INR monitor, obtaining at least one blood sample, provision of instructions for reporting home INR test results, and documentation of patient's ability to perform testing and report results)
• G0249 (Provision of test materials and equipment for home INR monitoring of patient with either mechanical heart valve[s], chronic atrial fibrillation, or venous thromboembolism who meets Medicare coverage criteria; includes: provision of materials for use in the home and reporting of test results to physician; testing not occurring more frequently than once a week; testing materials, billing units of service include 4 tests)
• G0250 (Physician review, interpretation, and patient management of home INR testing for patient with either mechanical heart valve[s], chronic atrial fibrillation, or venous thromboembolism who meets Medicare coverage criteria; testing not occurring more frequently than once a week; billing units of service include 4 tests).

Understand INR/PT relationship

Prothrombin Time (PT) is a test used to evaluate the extrinsic pathway clotting factors, often to monitor the dosing and therapeutic effectiveness of warfarin (brand name Coumadin) in coagulation control. Warfarin helps reduce clotting by impairing the effect of vitamin K in the liver, effectively reducing production of extrinsic pathway factors.

The PT lab test code is 85610 (Prothrombin time). The lab analyst performs the test by mixing reagents with the patient blood sample and noting the time when the plasma clots. When performed for a patient taking warfarin, the clotting time indicates the effectiveness of the medication at the current dosage. Labs express PT test results in seconds and/or as an INR number.

INR: Commercial thromboplastin reagents used in laboratory PT tests have different potencies, so the INR reporting method "normalizes" results by reporting the PT ratio that would result if the World Health Organization reference thromboplastin were used to perform the test.

Because PT is such a common test for monitoring warfarin therapy, as well as for other medical indications, many payers have policies concerning coverage rules, testing frequency, coding requirements, and more.

For a complete discussion of coagulation management coverage rules, see "3 Tips Show You How to Correctly Code PT Lab Tests" and "Follow Home PT/INR Monitoring Rules" in Pathology/Lab Coding Alert Vol. 18, No. 10.