1.3 Secondary Diagnoses Reporting & Present on Admission (POA) Indicators

AHIMA Certified Coding Specialist CCS

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1 Chapter 1: ICD-10-CM Diagnosis Coding Fundamentals & UHDDS Guidelines

1.1 ICD-10-CM Structure, Formats, and Core Conventions 1.2 UHDDS Principal Diagnosis Selection Rules 1.3 Secondary Diagnoses Reporting & Present on Admission (POA) Indicators

2 Chapter 2: Circulatory, Cardiac & Vascular Inpatient Coding

2.1 Hypertension, Hypertensive Heart & Chronic Kidney Disease, and CAD 2.2 Acute Myocardial Infarction (AMI) Types & Sequencing 2.3 Heart Failure Types, Acuity & Cardiomyopathy 2.4 Cerebrovascular Disease, Acute Stroke, and Late Effects

3 Chapter 3: Respiratory, Sepsis & Infectious Conditions Coding

3.1 Sepsis, Severe Sepsis, and Septic Shock Guidelines 3.2 Pneumonias, Aspiration Pneumonia, and Influenza 3.3 COPD, Asthma, and Acute Respiratory Failure

4 Chapter 4: Renal, Endocrine, Gastrointestinal & Nutritional Disorders

4.1 Acute Kidney Injury (AKI) & Chronic Kidney Disease (CKD) 4.2 Diabetes Mellitus Types, Manifestations & Complications 4.3 Protein-Calorie Malnutrition & Endocrine Emergencies 4.4 Gastrointestinal Bleeding, Ulcers, and Acute Abdominal Pathologies

5 Chapter 5: Neoplasms, Obstetrics, Perinatal, Injury & Trauma Coding

5.1 Neoplasm Table, Primary, Secondary & Encounters for Therapy 5.2 Obstetrics, Normal/Complicated Deliveries & Puerperium 5.3 Perinatal Conditions & Congenital Malformations 5.4 Traumatic Injuries, Fractures & 7th Character Extensions

6 Chapter 6: ICD-10-PCS Architecture, Conventions & Approaches

6.1 ICD-10-PCS 7-Character System Architecture & Conventions 6.2 ICD-10-PCS The Seven Surgical Approaches 6.3 General PCS Guidelines & Multiple Procedure Rules

7 Chapter 7: ICD-10-PCS Root Operations: Cutting Out, Taking Out & Altering Body Parts

7.1 Excision vs Resection vs Destruction 7.2 Extraction, Drainage, and Extirpation 7.3 Detachment & Amputation Coding 7.4 Release vs Division

8 Chapter 8: ICD-10-PCS Root Operations: Putting In, Putting Back & Moving Body Parts

8.1 Replacement vs Supplement vs Insertion 8.2 Reposition, Transfer, and Reattachment 8.3 Bypass, Dilation, Occlusion, and Restriction

9 Chapter 9: High-Volume Inpatient Surgical & Medical Procedures in ICD-10-PCS

9.1 Coronary Artery Bypass Grafting (CABG) & Percutaneous Coronary Interventions 9.2 Total Joint Arthroplasties & Spinal Fusion 9.3 Mechanical Ventilation & Extracorporeal Therapies

10 Chapter 10: Outpatient CPT & HCPCS Level II Coding & Modifiers

10.1 CPT Evaluation and Management (E/M) Guidelines 10.2 CPT Surgical, Radiology, Pathology & HCPCS Level II Coding 10.3 CPT Modifiers in Hospital Outpatient & Professional Coding

11 Chapter 11: Inpatient Record Review, Clinical Validation & Documentation Integrity

11.1 Inpatient Health Record Analysis & UHDDS Documentation Hierarchy 11.2 Clinical Validation of Diagnoses vs Coding Compliance 11.3 Identifying Reportable Secondary Conditions & Complications

12 Chapter 12: Compliant Provider Queries & AHIMA/ACDIS Standards

12.1 AHIMA/ACDIS Compliant Query Standards & Ethical Principles 12.2 Compliant Query Formats: Open-Ended, Multiple-Choice & Yes/No 12.3 High-Impact Clinical Query Scenarios & Provider Workflow

13 Chapter 13: Inpatient Prospective Payment System (IPPS) & MS-DRG Mechanics

13.1 IPPS Reimbursement Structure & MS-DRG Grouping Logic 13.2 Complications and Comorbidities (CC) & Major CC (MCC) Impact 13.3 All-Patient Refined DRG (APR-DRG) System 13.4 Inpatient Transfer Policies, Cost Outliers & Short-Stay Rules

14 Chapter 14: Outpatient Reimbursement, Coding Edits & Fraud/Abuse Compliance

14.1 Hospital Outpatient Prospective Payment System (OPPS) & APCs 14.2 National Correct Coding Initiative (NCCI) Edits & MUEs 14.3 Hospital-Acquired Conditions (HAC) Reduction & Quality Programs 14.4 Healthcare Fraud, Abuse Laws, Audits & AHIMA Ethical Standards

15 Chapter 15: Health Information Technology, CAC, Encoders & Data Security

15.1 Electronic Health Records (EHR) & Computer-Assisted Coding (CAC) 15.2 Logic-Based Encoders, Groupers & Health Data Systems 15.3 HIPAA Privacy/Security, Cybersecurity & Internal Coding Audits

1.3 Secondary Diagnoses Reporting & Present on Admission (POA) Indicators

Key Takeaways Explain This Topic AI

UHDDS defines secondary (other) diagnoses as conditions that coexist at admission, develop subsequently, or affect care by requiring clinical evaluation, therapeutic treatment, diagnostic procedures, extended length of stay, or increased nursing monitoring.

Abnormal laboratory, radiologic, or pathology findings must never be coded solely on test values; physician documentation must explicitly confirm the diagnosis and its clinical significance.

Present on Admission (POA) reporting applies to principal and other diagnoses on applicable inpatient claims using CMS indicators Y, N, U, W, and 1; indicator 1 denotes a code exempt from POA reporting.

Under CMS Hospital-Acquired Condition (HAC) payment provisions, preventable secondary conditions with a POA indicator of 'N' or 'U' do not qualify for CC/MCC MS-DRG severity tier elevation.

Last updated: August 2026

Secondary Diagnoses Reporting & Present on Admission (POA) Indicators

AHIMA CCS Exam Focus: Inpatient coders must accurately identify reportable secondary diagnoses and assign the correct Present on Admission (POA) indicator to reportable diagnoses on applicable inpatient claims, using the CMS exemption indicator for codes on the POA-exempt list. On the CCS exam, you will encounter questions evaluating whether chronic conditions meet reporting thresholds, whether abnormal laboratory findings can be coded without physician documentation, and how POA flags affect Complication or Comorbidity (CC) and Major Complication or Comorbidity (MCC) status under the CMS Hospital-Acquired Condition (HAC) reduction rules.

1. UHDDS Secondary ("Other") Diagnoses Criteria

The Uniform Hospital Discharge Data Set (UHDDS) defines "Other Diagnoses" (secondary diagnoses) as:

"All conditions that coexist at the time of admission, that develop subsequently, or that affect the treatment received and/or the length of stay."

The 5 UHDDS Clinical Reporting Criteria

For a co-existing or newly developing condition to be reported as a secondary diagnosis, it must satisfy at least ONE of the following five clinical criteria during the inpatient stay: UHDDS Reporting Thresholds (Must Meet ≥ 1)

┌─────────────────────────┬─────────────────────────┬─────────────────────────┐
│ 1. Clinical Evaluation │ 2. Therapeutic Treatment│ 3. Diagnostic Procedures│
├─────────────────────────┼─────────────────────────┼─────────────────────────┤
│ 4. Extended Length Stay │ 5. Increased Nursing Care and/or Monitoring │
└─────────────────────────┴─────────────────────────┴─────────────────────────┘

Clinical Evaluation: Documented physician assessment, bedside examination, progress note monitoring, or specialist consultation (e.g., endocrinology consult for poorly controlled hyperglycemia).

Therapeutic Treatment: Administration of prescription medication, IV fluid titration, respiratory therapy, surgery, physical therapy, or specific dietary modifications (e.g., initiating sliding-scale insulin, potassium repletion).

Diagnostic Procedures: Laboratory tests, imaging studies, biopsies, cardiac telemetry, or specialized physiological monitoring performed specifically to evaluate the condition (e.g., serial troponins, echocardiogram, renal ultrasound).

Extended Length of Hospital Stay: The condition directly prolongs the patient's hospitalization beyond what was expected for the principal diagnosis (e.g., patient kept an extra 48 hours for IV antibiotic desensitization or monitoring of cardiac arrhythmia).

Increased Nursing Care and/or Monitoring: Special nursing interventions, strict intake/output (I&O) recording, frequent neurological checks, complex wound dressing changes, or aspiration precautions.

Reporting Chronic Conditions

A documented chronic condition is reportable when it meets the same UHDDS additional-diagnosis criteria as any other condition—for example, it is evaluated, treated, monitored, increases nursing care, or extends the stay. Continuation or adjustment of medication, relevant laboratory or respiratory monitoring, and effects on procedural planning can demonstrate that a condition affected care. Do not report a chronic diagnosis merely because it appears on a problem list; verify that the record shows a qualifying effect on the current stay.

Historical Conditions & Conditions Not Meeting Criteria

Conditions that No Longer Exist: Conditions previously resolved or cured (e.g., resolved childhood asthma, prior appendectomy) that have no bearing on current medical decision-making are not reportable .

Personal/Family History Codes (Z80–Z87): May be reported as secondary diagnoses only if the historical condition influences current treatment, surveillance, or procedural approach (e.g., Z87.891 Personal history of nicotine dependence , Z85.3 Personal history of malignant neoplasm of breast for a patient on maintenance tamoxifen therapy).

Incidental Findings: An incidental finding on a diagnostic report (e.g., asymptomatic simple liver cyst on CT scan, mild asymptomatic diverticulosis) that receives no evaluation, monitoring, or treatment does not meet UHDDS criteria and must not be coded.

2. Coding Abnormal Laboratory and Diagnostic Findings (Guideline III.B)

One of the most critical compliance rules in medical coding governs abnormal diagnostic test values:

Strict Compliance Directive: Coders must NEVER assign a diagnosis code based solely on an abnormal laboratory, radiologic, or pathology finding . A diagnosis code can only be assigned if the treating physician documents the clinical condition and confirms its clinical significance in the medical record.

Clinical Documentation Scenario Coding Action Clinical / Regulatory Rationale

Lab report shows Serum Potassium: 2.9 mEq/L (Low). Physician progress note states: "Hypokalemia, start IV KCl repletion." Assign code E87.6 (Hypokalemia) Physician explicitly documented the diagnosis and initiated therapeutic treatment.

Lab report shows Serum Sodium: 126 mEq/L (Low). Progress notes and discharge summary contain no mention of hyponatremia or sodium abnormality. DO NOT CODE Coders cannot assign the diagnosis from the laboratory value alone; doing so would be unsupported coding, and knowingly billing an unsupported code can create compliance liability.

Discharge summary lists: "Patient received 2 units packed red blood cells for acute drop in Hgb from 13.5 to 7.2 g/dL following surgery." Provider did not write the word "anemia." Generate a Physician Query Clinical indicators support a significant condition, but the provider must document the diagnostic term (e.g., Acute posthemorrhagic anemia D62 ).

3. Present on Admission (POA) Reporting Guidelines

Under the Deficit Reduction Act (DRA) of 2005 , Present on Admission (POA) reporting is federally mandated for all diagnosis codes submitted on UB-04 (CMS-1450) and 837I electronic institutional claims by acute care Inpatient Prospective Payment System (IPPS) hospitals.

Legal Definition of POA
"Present on Admission is defined as present at the time the order for inpatient admission occurs."

Critical Timing Rule: Conditions that develop during an outpatient encounter (such as in the Emergency Department, Observation Care, or Outpatient Surgery ) BEFORE the formal inpatient admission order is written are classified as PRESENT ON ADMISSION ( Y ) . Timeline of Inpatient Stay and POA Determination:

[ED / Observation Stay] ───────► [Inpatient Admission Order Written] ───────► [Inpatient Care / Discharge]
└─── Conditions Arising HERE = 'Y' ───┘ └─── Conditions Developing HERE = 'N' ───┘
The 5 Official POA Indicators

Indicator Title Official Definition & Application Guidelines

Y Yes Present at the time the order for inpatient admission occurs. Includes chronic conditions, acute conditions presenting at admission, and conditions diagnosed subsequently that clearly existed prior to the inpatient admission order.

N No NOT present at the time the order for inpatient admission occurs. Represents conditions that developed during the acute inpatient stay (e.g., hospital-acquired infections, post-op complications, in-hospital trauma).

U Unknown Documentation is insufficient to determine if condition was present on admission. Coders should query the physician before assigning 'U'. CMS treats 'U' identically to 'N' for payment purposes.

W Clinically Undetermined Provider is unable to clinically determine whether the condition was present at admission or not. Used when the physician explicitly states in the record that it cannot be determined whether the disease was present on admission. CMS treats 'W' as 'Y' (exempt from penalty).

1 Unreported / Not used (POA-exempt code) Code is on the CMS POA Exempt List. Used for codes that do not represent active clinical illnesses (e.g., normal birth status Z38.- , external causes of injury V00–Y99 , personal history Z85–Z87 ).

4. CMS Hospital-Acquired Conditions (HAC) & DRG Impact

To incentivize patient safety, Medicare established the Hospital-Acquired Condition (HAC) Reduction Policy . Under this statute, CMS identifies specific high-cost, high-volume conditions that are considered reasonably preventable through evidence-based clinical guidelines.

Key CMS HAC Categories
Foreign Object Retained After Surgery ( T81.5- )
Air Embolism ( T80.0- , T81.7- )
Blood Incompatibility ( T80.3- )
Stage 3 and Stage 4 Pressure Injuries acquired in-hospital ( L89.- )
In-Hospital Falls and Trauma (Fractures, dislocations, intracranial injuries sustained in hospital)
Catheter-Associated Urinary Tract Infection (CAUTI) ( T83.511- )
Vascular Catheter-Associated Bloodstream Infection (CLABSI) ( T80.211- )
Surgical Site Infections (SSI) following orthopedic, CABG, or bariatric surgery

Manifestations of Poor Glycemic Control (Diabetic ketoacidosis, hyperosmolar coma, hypoglycemic coma developing in-hospital)

Deep Vein Thrombosis (DVT) / Pulmonary Embolism (PE) following total knee or total hip replacement
The HAC Payment Mechanism

In the Inpatient Prospective Payment System (IPPS), a secondary diagnosis can function as a Complication or Comorbidity (CC) or a Major Complication or Comorbidity (MCC) , significantly increasing the MS-DRG relative weight and hospital reimbursement.

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Financial Consequence: If a patient develops a Stage 4 hospital-acquired pressure injury (an MCC) while hospitalized ( POA = N ), CMS MS-DRG software suppresses the MCC status of that pressure ulcer. If no other MCC exists on the claim, the hospital is paid at the lower base MS-DRG rate, preventing the hospital from profiting from the complication.