Medical Coding Best Practices for Emergency Departments

Delivering quality care, while ensuring effective clinical documentation and compliant medical coding is even more challenging in emergency departments, which are fast-paced environments spread across multiple specialties presenting unique medical coding and billing challenges. Alongside knowledgeable clinical staff, specialized medical coders and billers with the requisite experience and strong analytical skills are required to obtain necessary reimbursements.  



In this paper, we share our perspectives on the unique medical coding and billing challenges  posed by emergency departments and the coding best practices to ensure optimal reimbursements.

Three Challenges impacting the quality of care and claim reimbursements in ED

  1. The nature of ED environment demands instant cognitive clinical decisions and shorter execution time. This means that the clinical documentation time available to providers is limited leading to high instances of discharges not fully billed and denied claims.

  2. Timely Coordination of care between ED physicians and multiple faculty staffs and documentation of the same is pivotal for the coders to distinguish physician/professional services vs facility services rendered by nurses and ancillary staff.

  3. Longer ED stays are often subject to scrutiny and audits. ED stays, longer than a day, require supporting medical necessity and a careful review of clinical documentation by coders to classify ED services vs observation care.

Here are a few best practices to improve first pass ratio of ED Claims and improve reimbursements while being compliant

1. Recognize that Emergency Departments are at a Critical Intersect of Care

The Emergency Department lies at the intersect of outpatient and inpatient services. The claim cycle, therefore, diverges into two paths:

  • Professional Coding and billing through CMS 1500 representing physician services rendered

  • Facility coding and billing through UB 04 representing facility services rendered

2. Understand Key Documentation Attributes that Influence ED level

  • Irrespective of the type of care (Professional or Facility), it is imperative that the physicians, nursing and support staff capture complete details for all medical services rendered. Electronic ED charting tools and medical scribes assist Physicians to focus on the quality of care yet making sure to capture the required clinical documentation important to determine the professional ED level.

  • The facility ED level, on the other hand, is determined by the extent of services rendered by nursing and ancillary staff. ACEP (American College of Emergency Physicians) recommends a coding model that references possible Interventions/procedure examples and complexity of discharge instructions that serve as a proxy referencing the typical intensity of facility services provided for patients requiring them

3. Educate Physicians on Documentation Requirements

Educating ED clinicians on clinically significant and relevant documentation is key to achieving compliant coding and optimizing end revenue/reimbursement.

  • The adoption of EMR/ EHR template, that is inbuilt in most of the practice management system aids better clinical documentation using the cues available.

  • Coding and Clinical Documentation Improvement experts can help institutionalize comprehensive documentation practices, through iterative reviews and education of providers.

  • Professional ED level is determined by documentation around the history of presenting illness, physical examination in addition to capturing all procedures and work up rendered.

  • On the facility side, an emphasis is required on documentation of start and stop times, mode/route of administration etc. when handling hydration, injections, and infusions.

4. Know Your CPT Coding Rules to Avoid Up/Down Coding

It is important that the coders correctly understand coding guidelines associated with determining the ED level and ancillary procedure codes reported along. The coding rules for ED level on the physician side are driven by the 3 key components – history, exam, and MDM (Medical Decision Making). For the facility side, the rules are more flexible that each hospital can establish their own billing guidelines taking into consideration general directions restated by OPPS (Outpatient Prospective Payment System).

5. Role of Modifiers in ED coding - the Key to Avoiding Denials 

Modifier assignment plays a pivotal role in determining the inclusive services vs separately payable services. The commonly used modifiers in ED, include – Modifier 25, Modifier 76 and 77, GC Modifier, Modifier 59/ X(EPSU), Modifier 91, and Modifier QW. It is important for the medical coders to have the right understanding of the coding guidelines that drive the appropriate modifier selection and avoid non-compliance. 

6. Commonly Overlooked Coding Guidelines

  1. Splint application is reported only when it is an initial service or a replacement service performed without a restorative treatment or procedure to stabilize or protect a fracture, injury or dislocation

  2. Service performed outside ED is not to be charged on the ED claim

  3. Determining a code of choice between Level 3 and 4 on professional ED coding could be tricky as both the levels support Moderate complexity MDM

  4. Self-administration drugs are not to be assigned credit

7. Ascertain Diagnosis Specificity to Avoid Medical Necessity Denials

The medical necessity in an ED set up is determined by the severity of patient’s medical condition that necessitated the service to be rendered in an ED set up over a scheduled outpatient visit.  

  1. The coders require high comprehension skills to narrow down to most specific diagnosis that necessitated the ED visit.

  2. Office of Inspector General (OIG) audits typically look at cases, wherein some providers held the patient for more than what is required in the ED, as non-compliant

  3. Code to the highest degree of specificity. A confirmed diagnosis takes over a related sign/symptom

  4. Reporting the appropriate sequential order of diagnosis is important while coding injury cases associated with worker’s compensation

  5. Admit and discharge diagnosis are reported separately on the facility front.

8. Critical Care, a Critical Branch of ED coding

Critical care is rendered when there is a life-threatening deterioration in the patient’s condition. These are time-based codes that carry specific coding guidelines with specifications around the frequency of reporting and list of services that are considered bundled. 

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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