Settling on a Secondary Diagnosis: Part I

EDITOR’S NOTE: This is the first in a two-part series on the subject of secondary diagnosis.

I have read a lot of literature regarding secondary diagnoses, and the typical dogma is that a condition must meet one of the following criteria to be considered codable, according to the ICD-10-CM Official Guidelines for Coding and Reporting, for the 2017 fiscal year:

For reporting purposes, the definition for “other diagnoses” is interpreted as additional conditions that affect patient care in terms of requiring:
 
1.   Clinical evaluation or
2.   Therapeutic treatment or
3.   Diagnostic studies or
4.   An extended length of stay or
5.   Increased nursing care and/or monitoring

 
Please note that it reads “is interpreted,” and does not express an imperative.

This list is actually commentary on the Uniform Hospital Discharge Data Set (UHDDS) intended to standardize hospital data reporting. Those data elements and definitions are found in the July 31, 1985 Federal Register (Vol. 50, No, 147), pp. 31038-40 (Federal Register Vol 50, No 147). The original instructions state that “other diagnoses are designated and defined as: all conditions that coexist at the time of admission, that develop subsequently, or that affect the treatment received and/or length of stay. Diagnoses … related to an earlier episode which have no bearing on the current hospital stay are to be excluded.”

The phrase that led to the criteria listed above is “…that develop subsequently, or that affect the treatment received and/or length of stay.” If a problem or complication arises during the hospitalization, there is invariably some work-up, treatment, or increase in the length of stay, thus meaning the criteria are met.

My opinion is that the intent of these instructions was primarily to prevent coders from picking up diagnoses from prior encounters that have no relevance to the current admission (…diagnoses … related to an earlier episode which have no bearing on the current hospital stay are to be excluded”). If a condition has no bearing on the current encounter, it should not enter into the calculation of severity or complexity of illness.

What causes a clinician to record a diagnosis that is not relevant? Discounting documentation of extraneous diagnoses for nefarious purposes of fraud, there are probably three main reasons.

The biggest contributor likely stems from the electronic medical record being able to propagate diagnoses in perpetuity, with providers not cultivating the problem list, thereby carelessly importing problem list diagnoses into the assessment and plan section. This can be compounded by the fact that many providers do not understand the difference between “history of” and a chronic condition.

Often, the problem list diagnoses and corresponding ICD-10-CM codes are selected by the healthcare provider (HCP), not a certified, trained coder. They frequently select convenient, albeit erroneous, codes. They type in “P-U-L-M-O-N-A-R-Y E-M-”, and then the electronic medical record (EMR) helpfully suggests I26.99 with the verbiage of “Pulmonary embolism.” Click! The HCP is satisfied and moves on. HCPs don’t know the difference between I26.99, Other pulmonary embolism without acute cor pulmonale; I27.82, Chronic pulmonary embolism; or Z86.711, Personal history of pulmonary embolism. Choosing a suboptimal code for your professional superbill is one thing; inserting it into a problem list that is never revised or edited, and that follows the patient forever, is another. Full disclosure: my personal belief is that doctors should concern themselves with providing excellent quality medical care and leave coding to the professionals, but that is a topic for a different day.

The final factor is providers that fail to take the time to actually think about the circumstances of each encounter and which conditions and diagnoses matter today. HCPs are being asked to increase productivity and use the EMR to record it, so copying and pasting is much more efficient than typing in a new assessment and plan each day. The only way to address this is to (shameless insertion of my personal motto) put “mentation” back into documentation.

So this explains how we end up with “left knee bursitis” from seven years ago in today’s documentation of an encounter for acute exacerbation of systolic congestive heart failure, and how coders must analyze whether each diagnosis is really a codable, current, clinically valid condition (or whether it is not relevant).

Next week, I will address an issue I believe derives from the misinterpretation of the UHDDS, and may be even more important. I will also try to give you strategies to approach these conundrums.

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Erica Remer, MD, FACEP, CCDS, ACPA-C

Erica Remer, MD, FACEP, CCDS, ACPA-C has a unique perspective as a practicing emergency physician for 25 years, with extensive coding, CDI, and ICD-10 expertise. As physician advisor for University Hospitals Health System in Cleveland, Ohio for four years, she trained 2,700 providers in ICD-10, closed hundreds of queries, fought numerous DRG clinical determination and medical necessity denials, and educated CDI specialists and healthcare providers with engaging, case-based presentations. She transitioned to independent consulting in July 2016. Dr. Remer is a member of the ICD10monitor editorial board and is the co-host on the popular Talk Ten Tuesdays weekly, live Internet radio broadcasts.

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