17.1 Present on Admission Clarification and Selected HAC Rules
Key Takeaways
Determine reportable diagnoses first, then assign POA using the inpatient admission order as the timing reference; earlier emergency, observation or outpatient-surgery conditions may be POA Y.
Distinguish U for insufficient documentation from W for clinical inability to determine timing, and use the applicable annual exemption and claim-reporting instructions.
For a code containing multiple clinical concepts, the general rule is N when a represented concept was not present on admission, with specific instructions such as infection/organism timing applied.
Final v44 lists stage 3/4 sacral pressure-ulcer codes as MCC/selected HACs, but L89.150 unstageable is neither listed as a CC/MCC in Appendix C Part 1 nor included in HAC 04.
A selected-HAC N/U payment exclusion does not guarantee a lower DRG, and a POA indicator alone does not establish a HACRP measure event or hospital-level penalty.
Present on Admission Clarification and Selected HAC Rules
Present on admission (POA) reporting describes the timing of a condition represented by an assigned diagnosis code. It does not decide whether the condition should be coded in the first place. Establish the reportable diagnoses under the applicable coding rules, then apply the FY2027 POA guidelines in Appendix I. Keep clinical onset, diagnosis date, code assignment, and payment or quality-program effects distinct.
Use the inpatient admission order as the reference point
POA means present when the order for inpatient admission occurs. A condition developing during an earlier emergency, outpatient surgery, or observation encounter is considered present on admission to the subsequent inpatient stay. It can have arisen in the hospital building and still be POA for that inpatient claim.
Hypothetical timeline: Observation begins Monday at 08:00. A provider establishes a new condition on Tuesday at 20:00, 36 hours later. The inpatient admission order occurs Wednesday at 08:00, 48 hours after presentation. If the condition is reportable and was present before that order, its POA indicator is Y. Do not use the patient's first arrival time or a 24-hour threshold to change that conclusion.
The date a diagnosis is first written does not necessarily establish onset. Appendix I sets no universal deadline by which a provider must identify a POA condition. A diagnosis recognized several days later may have been present at admission. Link the later diagnosis to the earlier findings through the applicable guidance and provider judgment; do not independently assign a diagnosis from those findings.
Distinguish the reporting options
| Option | Meaning | Important boundary |
|---|---|---|
| Y | Present at inpatient admission | Not proof that the condition originated outside the hospital |
| N | Not present at inpatient admission | Not automatically a selected payment HAC or a quality-measure event |
| U | Documentation is insufficient to determine timing | Not equivalent to a provider's clinical inability to determine timing |
| W | Provider cannot clinically determine whether it was present | Does not mean every inadequately documented case can be labeled W |
| Exempt/unreported | Code is exempt from POA reporting | Use the applicable annual exempt list and current reporting instructions |
U should be used only in limited circumstances; clarify unclear documentation when appropriate. W reflects a documented clinical determination that the timing cannot be established. Do not choose between them based on which payment outcome is more favorable.
The FY2027 guidelines instruct leaving the POA field blank for an exempt code. The CMS coding webpage also describes the historical “1” convention for 4010A electronic submission. That historical explanation is not permission to invent E as a national transmitted POA indicator. Consult the applicable claim instructions and the FY2027 exempt list. For example, Z87.891 is on that list; L89.150 is not.
POA reporting requirements apply to inpatient claims subject to the relevant laws and regulations. They include reportable principal and secondary diagnoses and applicable external-cause codes, with exemptions. They should not be described as an unqualified requirement for every diagnosis on every inpatient claim regardless of facility, payer, or exemption.
Apply the combination-code rule correctly
For a code containing multiple clinical concepts, Appendix I generally assigns N if at least one represented concept was not present on admission and Y if all were present. A chronic component alone does not make a later acute exacerbation POA Y.
For example, if chronic systolic heart failure was present at admission but an acute exacerbation first developed during the inpatient stay, the combined acute-on-chronic code I50.23 is POA N under this rule. Do not assign a different code merely to obtain Y. If separate codes appropriately represent separate conditions, assess their timing separately under the classification and applicable guidelines.
There are specific instructions to apply rather than an unrestricted slogan. For an infection code that includes its causal organism, assign Y when the infection or its signs were present at admission even if the culture result identifying the organism became available later. A result date is not automatically an onset date.
A diagnosis subsequently confirmed after admission can also be POA when appropriately suspected at admission or established as the cause of an admission symptom. For an uncertain diagnosis at discharge, apply the specified inpatient uncertain-diagnosis rules first and then the POA instructions based on the relevant admission findings. An early suspected condition that was ultimately ruled out does not become reportable merely because it appeared in the admission differential.
Check selected HAC membership and the whole case
The CMS selected-HAC payment provision arises from DRA section 5001(c). For the selected secondary diagnoses that meet the applicable criteria, N or U prevents additional payment attributable to that HAC; Y or W does not trigger that exclusion. This is not a promise of a higher DRG for every Y/W diagnosis or an automatic lower DRG for every N/U diagnosis. Other diagnoses, exclusions, procedures, and grouping logic can leave the result unchanged.
Use the exact annual diagnosis and, where required, procedure criteria in the final v44 definitions manual, Appendix I. CMS identifies 14 categories, including retained foreign object, air embolism, blood incompatibility, stage III/IV pressure ulcers, falls and trauma, specified glycemic-control manifestations, catheter-associated urinary or vascular infections, specified surgical-site infections, DVT/PE with specified hip or knee replacement, and pneumothorax with venous catheterization. Category names alone do not establish whether an individual code combination qualifies.
| Example requiring exact classification | Final v44 finding | Review implication |
|---|---|---|
| L89.153 or L89.154 | Sacral pressure ulcer stage 3 or 4; MCC and listed in HAC 04 | Apply actual stage, timing, and grouping criteria |
| L89.150 | Sacral pressure ulcer, unstageable; not listed as a CC/MCC in Appendix C Part 1 and not in HAC 04 | Do not apply the selected stage III/IV payment rule simply because the ulcer is unstageable |
| T80.211A | Central venous catheter bloodstream infection; CC and listed in HAC 07 | Do not describe it as an MCC or substitute a surveillance definition for the code's requirements |
| Specified postoperative infection or DVT/PE | Some categories require particular procedure codes | Do not treat every postoperative infection or every embolism as a selected HAC |
Use actual code titles. E11.00 describes type 2 diabetes with hyperosmolarity without coma; E11.01 is the corresponding with-coma code. E16.0 is drug-induced hypoglycemia without coma and is not the selected hypoglycemic-coma entry. These distinctions cannot be repaired by labeling all glycemic complications alike.
Preserve pressure-ulcer distinctions
FY2027 guideline I.C.12.a distinguishes an unstageable ulcer from an unspecified stage. If debridement reveals the stage of an unstageable ulcer, assign the revealed-stage code as directed. If an ulcer truly progresses from one stage at admission to a higher stage during the stay, assign the two site/stage codes required by the guideline. Revealing a previously obscured stage and clinical progression are different situations.
Review the actual diagnosis, permitted stage documentation, and chronology. A nursing assessment can support stage documentation under I.B.14; the associated pressure-ulcer diagnosis still requires the appropriate provider documentation. A skin finding within 12 or 24 hours is evidence to evaluate, not a universal POA proof rule. Do not invent an admission stage from the eventual severity.
Ask a neutral timing question when needed
Suppose the inpatient order is Monday at 14:00, a wound assessment at 16:00 documents a stage 3 sacral pressure ulcer, and the involved provider confirms that diagnosis the next morning. Earlier documentation leaves timing unclear. A POA query should cite those sources and ask whether the documented condition was present at the time of the inpatient admission order. Provide Yes, No, and Unable to determine, as required by the 2026 query brief.
Do not redefine Y as “present before arriving at the hospital,” assume that the 16:00 assessment proves onset after 14:00, or mention avoiding a HAC payment effect. Preserve the provider's assessment and apply the actual reporting rules to the response.
Finally, distinguish selected-HAC claim payment from the HAC Reduction Program. HACRP uses specified hospital-level measures and reduces applicable payments by 1% for hospitals in its worst-performing quartile. A single N indicator or selected-HAC code does not automatically establish a measure event or impose that hospital-level reduction. Apply the current measure population, exclusions, definitions, and program rules separately.
In a hypothetical encounter, outpatient observation begins Monday at 08:00. The involved provider documents that acute pyelonephritis developed Tuesday at 20:00. The inpatient admission order occurs Wednesday at 08:00. If the condition is reportable, what POA conclusion follows for the inpatient claim?
N, because the condition arose more than 24 hours after the patient first entered the hospital.
U, because no condition developing in observation can receive an inpatient POA indicator.
Y, because the condition developed at hour 36 and was present before the inpatient order at hour 48.
W, because the condition developed within the hospital building.
A patient has documented chronic systolic heart failure at inpatient admission. The provider documents that its acute exacerbation first developed after the inpatient admission order. A single assigned code, I50.23, represents the acute-on-chronic condition. What is the POA indicator under the general multiple-clinical-concept rule?
N, because a represented acute component was not present at inpatient admission.
Y, because any one component being present is sufficient for a combination code.
W, because every acute-on-chronic code has clinically indeterminate timing.
Exempt, because all chronic conditions are on the POA-exempt list.
A newly developed sacral pressure ulcer is documented as unstageable and coded L89.150 with POA N. Which statement accurately applies the actual final MS-DRG v44 lists?
Every L89 code is an MCC and is automatically a selected payment HAC.
L89.150 is selected HAC 04, so the patient automatically triggers the hospital’s 1% HACRP reduction.
The code should be changed to stage 4 solely because the ulcer is unstageable.
L89.150 is not listed as a CC/MCC in Appendix C Part 1 and is not in selected HAC 04; stage 3/4 rules and hospital-level quality-program logic cannot be applied automatically.
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