Two More Best Practices to Improve Emergency Department Coding

Delivering quality care while ensuring effective clinical documentation and compliant medical coding is an ongoing challenge in a fast-paced emergency department (ED). This two-part series reviews best practices for optimizing coding compliance and reimbursement of ED claims. Last month, we explored best practices for improving provider documentation and coder education to ensure compliant ED coding. This month, we’ll focus on strategies to ensure proper modifier use and diagnosis code selection.



Best Practice No. 1: Know Modifier Requirements

Non-compliance usually results from a lack of knowledge, rather than intent. Modifiers are often misunderstood and, unwittingly, misused.

1. Modifier 25

In the ED, minor procedures commonly follow an initial evaluation and management (E/M) at the same encounter. To report a same-day encounter, E/M service with modifier 25 - Significant, separately identifiable evaluation and management service by the same physician or other qualified health care professional on the same day of the procedure or another service - appended, and the documentation must describe a standalone E/M service. In other words, you must be able to pick out all the elements of a billable E/M service from the documentation, apart from the documentation of other services or procedures provided during the same encounter.

2. Modifier 75 and 77

When reporting physician services, modifier 76 - Repeat procedure or service by the same physician or another qualified healthcare professional - and modifier 77 - Repeat procedure by another physician or other qualified healthcare professional - often cause confusion due to the similarity of their descriptors. Modifiers 76 and 77 indicate repeat services by the same or a different physician, respectively. Apply modifier 76 or 77 to the second and subsequent tests when repeated with substantial medical necessity documented. E.g.: services such as repeat bedside electrocardiograms (EKGs) interpreted by ED physicians.

3. Modifier 91

Modifier 91 - Repeat clinical diagnostic laboratory test - is distinct from modifiers 76 and 77, in that it specifically identifies repeat clinical diagnostic laboratory tests on the same day, for the same patient. This modifier is not appropriate when lab tests are repeated to confirm initial results due to testing problems with specimens or equipment, or for any other reason when a normal, one-time, reportable result is all that is required.

4. Modifier GC

EDs with residents must properly apply modifier GC. This service has been performed - in part by a resident under the direction of a teaching physician to indicate a resident’s services were rendered under the direction of a teaching physician - to indicate a resident’s services were rendered under the direction of a teaching physician. All resident services need an attestation. Per Medicare Learning Network guidelines for teaching physicians, interns, and residents, Medicare pays for services furnished in teaching settings through the Medicare Physician Fee Schedule (MPFS) if the services meet one of these criteria:

  • They are personally furnished by a physician who is not a resident

  • They are furnished by a resident when a teaching physician is physically present during the critical or key portions of the service

  • They are furnished by a resident under a primary care exception within an approved Graduate Medical Education program

Best Practices No. 2: Select Diagnoses to the Highest Documented Specificity

Medical necessity, reflected by a patient’s documented diagnosis(es), is required to establish the need for all services and procedures. When selecting diagnosis codes to support medical necessity in the ED, keep these points in mind:

  • Report the diagnosis listed by the physician in the final assessment and plan (A&P). You may use more specific information available elsewhere in the documentation, as well, but only if that information is not contradictory

  • Work-up ordered and relevant past medical history are additional cues to support a “medically necessary” diagnosis

  • Do not report findings listed under physical exam unless the provider documents clinical significance

  • In an outpatient setting (including the ED), do not code uncertain diagnoses termed such as “probable,” “suspected,” “questionable,” “rule out,” or “working diagnosis”.

  • A confirmed diagnosis must establish medical necessity for critical care services, versus “routine” emergency care

  • Do not report psychiatry conditions, such as suicidal ideation, as a discharge diagnosis because the patients with such conditions usually are not discharged until the condition is deemed stable

  • Always code a diagnosis to the highest degree of specificity (e.g., laterality, anatomical site, etc.)

  • Do not report related signs and symptoms in addition to a confirmed diagnosis. Report additional signs and symptoms only if they are unrelated to a confirmed diagnosis

  • Code chronic diseases that coexist only when they require or affect patient care

  • Admit and discharge diagnoses are reported separately on the facility front. The admit diagnosis indicates the reason for the encounter, which is usually the clinical sign/symptom the patient presents with. The discharge diagnosis, in most cases, is the confirmed diagnosis the patient is treated for

  • It is appropriate to report the diagnosis that resolved during the ED encounter (e.g., asthma exacerbation resolved with a nebulizer)

  • Assigning appropriate external causes codes is vital for Workers’ Compensation claims. You may assign as many external cause codes to completely describe the information documented, but never use these codes as a principal or first-listed diagnosis

  • When assigning ICD-10-CM codes for injury cases, the recommended sequencing is:

    • Injury code (S and T series codes that indicate fracture, dislocation, sprains, etc.)

    • Cause of injury/intent (V, W, X, Y series codes that indicate accidents, tripping, slipping, fall, etc.)

    • Place of occurrence (Y92 Place of occurrence of the external cause series). Do not code a place of occurrence code (Y92.9 - Unspecified place or not applicable) if the place is not stated or is not applicable

    • Activity code (Y93 Activity codes to indicate walking, running, climbing, etc.). Do not assign Y93.9 Activity, unspecified if the activity is not stated

    • Status code (Y99 External cause status to indicate leisure, work, etc.)

About the Author:

Gayathri Natarajan is a certified professional coder with over a decade of experience in leading large-scale medical coding teams across a diverse range of specialties. As the director of coding services, she provides leadership to education & training programs, compliance, medical coding process automation, and process transition activities at Access Healthcare.

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*originally featured in AAPC's Healthcare Business Monthly