HI410 Unit 8 Medical Necessity Review Example

One Night After a Faint, One Lab Test Under the Wrong Diagnosis: A Unit 8 Medical Necessity Review That Tests Each Encounter Against the Rule That Governs It

[Student Name]

Purdue University Global

HI410: Advanced Reimbursement Methodology

Unit 8 Medical Necessity Review

[Instructor Name]

[Date]

Both encounters, the patients and the amounts are composite; the regulations and manuals cited are real.

The Standard Used in This Review

Medical necessity is decided by what the record shows at the time of the decision, not by how the patient turned out. An admission is judged by what the admitting physician knew and expected when the order was written. A test is judged by the reason the ordering practitioner gave for it. Both encounters below are reviewed in the same four steps: the rule, the record, the finding and the consequence.

Encounter 1: A One-Night Inpatient Stay After Syncope

The rule. Medicare treats an inpatient order as reasonable when the physician who writes it anticipates hospital care lasting past a second midnight, and the record has to show what that anticipation rested on (42 C.F.R. § 412.3). An admission expected to last a shorter time can still be appropriate in limited cases, but the record must then explain why inpatient care was needed. The record. A composite 74-year-old woman fainted while standing in line at a pharmacy and arrived by ambulance at 16:40. The admission order, signed at 21:15, reads "admit to inpatient, telemetry, syncope." The admitting note records a normal first troponin, an electrocardiogram showing sinus rhythm with no acute changes, orthostatic vital signs that were mildly positive, and a plan: "telemetry overnight, echo in AM, likely discharge if negative." The echocardiogram the next morning was normal, telemetry showed no arrhythmia, and the patient went home at 15:30 the next day after one midnight. What the note contains: a clear assessment, a reasonable plan and a documented low-risk workup. What it lacks: any statement that the physician expected care across two midnights, and any risk factor, such as a high-risk electrocardiogram, a structural heart finding or an injury from the fall, that would explain why the stay needed to be inpatient rather than observation. The phrase "likely discharge if negative" points the other way: it records an expectation of a short stay. The admitting note does not fail because the patient went home quickly; it fails because it shows the physician expected her to. The finding. The inpatient admission is not supported. The workup itself was appropriate and necessary; the patient status was not. The consequence. Because the patient has already been discharged, the hospital cannot use the process that changes an inpatient order to outpatient before discharge, which works only before discharge and only with the physician's agreement. The hospital should therefore not bill the stay as an inpatient admission. It can bill the services that would have been payable had the patient been an outpatient, such as the telemetry monitoring and the echocardiogram, under the outpatient benefit, within the timely filing limit. The inpatient payment of about $5,180 is replaced by outpatient payments of about $2,240, both composite figures for this exercise.

Encounter 2: An Outpatient Vitamin D Test

The rule. A diagnostic laboratory test must be ordered by the practitioner who is treating the patient and who uses the result in the patient's care (42 C.F.R. § 410.32). Where a local coverage determination lists the conditions for which a test is covered, the claim must carry a diagnosis the policy accepts, and the review contractor will deny the line otherwise (Centers for Medicare & Medicaid Services [CMS], 2024b). When a provider expects that a test may not be covered, the patient must receive an advance beneficiary notice before the test if the provider wants to bill the patient for it. The record. A composite 68-year-old man saw his primary care physician for a follow-up visit. The lab requisition for a 25-hydroxy vitamin D level lists one diagnosis, fatigue. The local coverage policy in the supplied packet covers the test for conditions including chronic kidney disease, malabsorption, osteoporosis and long-term use of certain anticonvulsants, and it lists fatigue alone as not covered. No advance beneficiary notice was signed. The progress note for the same visit, however, records "CKD stage 3b, eGFR 38, check vitamin D and PTH given CKD-mineral bone disorder risk." The finding. Medical necessity existed and was documented. The test was ordered for a covered reason, and the treating physician wrote that reason in the progress note on the day of the order. The gap is in the order form, which carried the wrong diagnosis. The consequence. The line will be denied as billed. The gap is correctable, but not by the hospital laboratory or its coders. A testing facility relies on the diagnosis supplied by the ordering practitioner and may not choose a better diagnosis from the record on its own. The correct path is to ask the ordering physician's office to clarify or amend the order to reflect the documented reason, after which the claim can be corrected and resubmitted. Because no advance beneficiary notice was signed, the patient cannot be billed for the test if the line remains denied; the claims manual places that liability on the provider (Centers for Medicare & Medicaid Services, 2024a).

Comparison of the Two Encounters

1. Encounter 1. Rule: two-midnight expectation. Supported: no. Correctable: no, as an inpatient claim; partly, through outpatient billing. Financial consequence: about $2,940 less than the inpatient payment. Preventive control: physician advisor review of inpatient orders for short-stay diagnoses before discharge.

2. Encounter 2. Rule: local coverage determination and ordering practitioner's diagnosis. Supported: yes, in the progress note. Correctable: yes, through the ordering physician. Financial consequence: the test payment, about $40, collected once corrected. Preventive control: a diagnosis check against the coverage policy at the time of order entry, with a prompt to the ordering practitioner when the diagnosis is not on the covered list.

What the Two Cases Teach Together

The two encounters fail for opposite reasons. In the first, the documentation is complete and accurate, and that is what defeats the claim: it shows a physician who expected a short stay. In the second, the documentation supports the test, but the one field that reaches the claim does not. Reimbursement texts describe medical necessity as a property of the record, not of the service (Casto & White, 2021), and both cases show why. A health information professional's job here is not to rescue a claim with better words after the fact. It is to find where in the process the record and the claim came apart, and to put the control there.

References

Casto, A. B., & White, S. (2021). Principles of healthcare reimbursement and revenue cycle management (7th ed.). AHIMA Press.

Centers for Medicare & Medicaid Services. (2024a). Medicare claims processing manual, Chapter 30: Financial liability protections.

Centers for Medicare & Medicaid Services. (2024b). Medicare program integrity manual, Chapter 13: Local coverage determinations.

42 C.F.R. § 410.32 (2024). https://www.ecfr.gov/current/title-42/section-410.32

42 C.F.R. § 412.3 (2024). https://www.ecfr.gov/current/title-42/section-412.3