1.3 Chapter-Specific and Setting-Specific Coding Guidelines

AHIMA Certified Documentation Integrity Practitioner CDIP

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1 Chapter 1: Authoritative Coding Resources & Conventions

1.1 Official Coding Resources: Scope, Authority & Research 1.2 General Coding Conventions, Punctuation & Instructional Notes 1.3 Chapter-Specific and Setting-Specific Coding Guidelines

2 Chapter 2: Principal & Secondary Diagnosis Determination

2.1 UHDDS Definitions & Principal Diagnosis Selection 2.2 Two or More Diagnoses Equally Meeting Criteria 2.3 Secondary Diagnosis Reporting Standards & POA Status

3 Chapter 3: Procedure Coding & Sequencing Standards

3.1 ICD-10-PCS Root Operations & Inpatient Procedure Coding 3.2 Principal Procedure Selection & Surgical Sequencing 3.3 Applying Official References to Ambiguous Records

4 Chapter 4: Inpatient Prospective Payment & DRG Grouping

4.1 MS-DRG Logic, CC/MCC Exclusions & Severity Levels 4.2 Working vs. Final DRG Assignment & Optimization vs. Maximization 4.3 CDI-Coding Reconciliation & Annual Regulatory Updates

5 Chapter 5: Enterprise CDI Promotion & Program Value

5.1 Articulating CDI Value to C-Suite & Hospital Leadership 5.2 Organizational Models, Inpatient/Outpatient Scope & Staffing 5.3 Cross-Functional Collaboration: HIM, Quality & Case Management

6 Chapter 6: Cross-Functional Alignment & Improvement Projects

6.1 Partnering with Nursing, Pharmacy & Allied Health Professionals 6.2 Documentation Improvement Project Identification & Scoping 6.3 Executing, Piloting & Measuring CDI Project Outcomes

7 Chapter 7: Physician Champion Engagement & Clinical Advocacy

7.1 Selection, Role & Credibility of the CDI Physician Champion 7.2 Peer-to-Peer Engagement, Coaching & Overcoming Resistance 7.3 Developing Standard CDI Operational Policies & Procedures

8 Chapter 8: Compliant Policy Architecture & Query Governance

8.1 AHIMA/ACDIS Practice Brief Standards in Policy Construction 8.2 Medical Record Integration of Provider Query Responses 8.3 Policies for Electronic, Paper, and Verbal Query Communications

9 Chapter 9: Query Escalation & Professional Communication

9.1 Chain of Command & Protocols for Unanswered Queries 9.2 Conflict Resolution & Professional Feedback Mechanisms 9.3 Assessing Stakeholder Learning Needs & Specialty Curricula

10 Chapter 10: Educational Delivery & Broader Healthcare Impacts

10.1 Delivery Methods: Microlearning, Case Studies & Grand Rounds 10.2 Documentation Impacts on Clinical Research & Epidemiology 10.3 Documentation Impacts on Case Management, LOS & Reimbursement

11 Chapter 11: Clinical Record Synthesis & Encounter Trajectory

11.1 Synthesizing Provider Notes, Consults & Progress Trajectory 11.2 Interpreting Diagnostic Imaging, Pathology & Labs 11.3 Resolving Conflicting, Ambiguous & Copy-Forward Entries

12 Chapter 12: Advanced Clinical Concepts & Review Prioritization

12.1 Pharmacotherapy, Clinical Trajectories & Disease Correlations 12.2 Inpatient Review Prioritization: High-Risk & High-Volume 12.3 Payer Prioritization, Length of Stay & Re-Review Cadence

13 Chapter 13: Clinical Indicator Mapping & Gap Recognition

13.1 Systematic Identification of Documentation Gaps 13.2 Sepsis Definitions, SEP-1, and Coding 13.3 AKI Criteria, Tubular Injury, and CKD Staging

14 Chapter 14: Diagnostic Precision in High-Impact Conditions

14.1 Respiratory Failure: Acuity, Evidence, and Sequencing 14.2 Heart Failure Phenotype, Acuity, and Hypertensive Combinations 14.3 Encephalopathy, Delirium, and Acute Cognitive Change

15 Chapter 15: Clinical Validation & Complication Discrepancies

15.1 Malnutrition Assessment, Severity, and Provider Documentation 15.2 Principles of a Compliant, Nonleading Query 15.3 Open-Ended, Multiple-Choice, and Yes/No Queries

16 Chapter 16: Query Mechanics & Direct Provider Collaboration

16.1 Electronic Query Systems, Templates, and Technology Oversight 16.2 Collaborating With the Appropriate Query Recipient 16.3 Capturing and Clarifying Query Responses

17 Chapter 17: Quality Indicators & Post-Discharge Clarification

17.1 Present on Admission Clarification and Selected HAC Rules 17.2 Clarifying Acuity, Cause, Site and Severity 17.3 Post-Discharge Query Opportunities and Limits 17.4 Managing Post-Discharge Query Workflows

18 Chapter 18: CDI Operational Dashboards & Quality Auditing

18.1 Departmental Metrics: Definitions, Calculations and Dashboard Use 18.2 Internal CDI Quality Audits and Reviewer Calibration 18.3 Query Trends: Understanding the Process and Provider Experience

19 Chapter 19: Benchmarking, Productivity & Data-Driven Workflow

19.1 Provider Documentation Benchmarking 19.2 External Benchmarking: CMI, Severity, Mortality and Length of Stay 19.3 Evaluating CDI Professional Performance 19.4 Using Data to Design CDI Workflow and Staffing

20 Chapter 20: Ethical CDI Standards & Regulatory Frameworks

20.1 Applying AHIMA Ethics to CDI Decisions 20.2 Responding to Financial Pressure and Upcoding Risks 20.3 Maintaining Competence and Professional Integrity

21 Chapter 21: Regulatory Compliance & Enforcement Landscapes

21.1 False Claims, Overpayments and Referral Laws 21.2 Regulatory Agencies, Review Contractors and Appeals 21.3 EHR Templates, Copied Text and Record Integrity

22 Chapter 22: Technology Risks & Second-Level Review Protocols

22.1 CAC, NLP and AI: Context, Oversight and Performance 22.2 Selecting Cases for Second-Level Review 22.3 Conducting and Closing a Second-Level Review

23 Chapter 23: Clinical Validation Queries & Risk Mitigation

23.1 Clinical Validation and Coding Clarification 23.2 Clinical Validation Queries and Denial Evidence 23.3 Detecting Leading, Biased and Unsupported Queries

24 Chapter 24: Noncompliant Query Remediation & Query Lifecycle Management

24.1 Query Remediation and Corrective Action 24.2 Query Timeframes, Aging and Measurement 24.3 Query Records, Retention and Evidence Preservation

1.3 Chapter-Specific and Setting-Specific Coding Guidelines

Key Takeaways Explain This Topic AI

Sections II and III address non-outpatient reporting, but their uncertain-diagnosis provisions have the narrower hospital-inpatient scope stated in II.H and III.C.

Outpatient uncertainty is addressed in IV.H; report the highest degree of certainty rather than assigning a suspected disease as established.

Urosepsis has no default Index code and requires provider clarification; sepsis sequencing depends on timing and applicable chapter-specific instructions.

Neoplasm sequencing depends on the treatment purpose and documented complication, with distinct rules for malignancy-associated anemia, therapy-associated anemia, and dehydration.

Respiratory-failure sequencing depends on admission circumstances; adverse effects, poisonings, underdosing, and toxic effects follow different drug-event coding pathways.

Last updated: October 2026

Start with the encounter setting and the reason for care

The same clinical wording can produce different coding decisions in different settings. The CDI reviewer must establish which reporting rules apply before deciding whether a diagnosis can be assigned or sequenced first. Chapter-specific instructions then address conditions such as sepsis, neoplasms, diabetes, and drug-related events.

The FY2027 ICD-10-CM Official Guidelines organize this work into four sections:

Section Main subject Applicability distinction

I Conventions, general guidelines, and chapter-specific guidelines Apply across settings unless otherwise indicated

• II Principal diagnosis selection Non-outpatient settings; read the scope of each provision
• III Additional diagnoses Non-outpatient reporting; conditions must meet applicable reporting requirements
• IV Outpatient diagnosis reporting Includes hospital outpatient services and provider-based office visits

Sections II and III are not restricted as a whole to acute hospital admissions. Their discussions describe the expanded use of UHDDS definitions in non-outpatient settings. However, the uncertain-diagnosis provisions within those sections have a narrower stated scope. Do not transfer one provision's limitation to an entire section or assume that every non-outpatient service uses the hospital uncertainty rule.

Uncertain diagnoses: timing, setting, and exceptions

Sections II.H and III.C permit coding qualifying uncertain diagnoses documented at discharge as if established for inpatient admissions to short-term, acute, long-term care, and psychiatric hospitals. The documentation may use terms such as probable, suspected, likely, or possible. Review the final diagnostic conclusions and applicable chapter-specific exceptions; an early differential that was subsequently ruled out does not satisfy this rule.

For example, an acute inpatient discharge summary may retain probable aspiration pneumonia after evaluation and treatment. The absence of a microbiologic confirmation does not by itself require replacing that final uncertain diagnosis with symptoms. In contrast, an admission note saying rule out pneumonia followed by a final conclusion that pneumonia was excluded does not support coding pneumonia as established.

Section IV.H directs outpatient reporting to the highest degree of certainty for the encounter, such as a confirmed condition, symptom, sign, abnormal finding, or other reason for the visit. Do not assign a suspected disease as established by importing the hospital inpatient rule. Observation is an outpatient service, even when the patient remains overnight in a hospital bed.

This distinction addresses diagnosis assignment, not an automatic severity or payment result. A reportable uncertain inpatient diagnosis still needs the correct complete code and sequence. Its effect on an MS-DRG depends on the versioned grouping rules and full claim.

Sepsis: distinguish documentation from sequence

Under Section I.C.1.d , assign the appropriate systemic-infection code for documented sepsis. If the infection or causal organism is not further specified, the guideline directs A41.9 , sepsis, unspecified organism. A positive culture is not itself the provider's diagnosis of sepsis.

Urosepsis has no default code in the Alphabetic Index. It is not synonymous with sepsis and does not default to urinary tract infection. Query the provider for clarification when this term is used; the resulting documentation determines the supported assignment.

For severe sepsis , code the underlying systemic infection, the appropriate complete code from R65.2- , and the associated acute organ dysfunctions. The minimum-two-code statement does not eliminate the requirement to report associated organ dysfunction. When the relationship between sepsis and an acute organ dysfunction is unclear, query rather than infer the relationship from coexistence.

Sequencing requires the admission circumstances and applicable instructions:

If severe sepsis is present on admission and meets the principal-diagnosis definition, sequence the underlying systemic infection as principal, with the required severe-sepsis and organ-dysfunction codes.

If admission is for a localized infection and sepsis develops afterward, the localized infection remains first under the applicable guideline.

Postprocedural and obstetric infections have specific sequencing instructions. Postprocedural septic shock follows its own pathway; R65.21 , severe sepsis with septic shock, is not assigned for postprocedural septic shock.

Other specific situations, including infection-associated hemolytic-uremic syndrome, can direct a different principal diagnosis.

Thus, a septic-shock or severe-sepsis code cannot be principal, but that does not establish that a systemic-infection code must be principal in every case. Never use a generic three-line sequence as a substitute for the scenario's timing and chapter-specific rules.

Neoplasms: identify what the admission treats

Section I.C.2 distinguishes treatment of a malignancy, treatment of a secondary site, administration of therapy, and management of complications. The presence of cancer does not establish a universal principal diagnosis.

Stated circumstances Guideline direction

Malignancy chiefly responsible for admission, treatment directed at primary site Primary malignancy is principal, subject to the specified therapy exception

Treatment directed solely at a secondary malignant site Secondary malignancy is principal even if the primary remains present

Encounter chiefly for antineoplastic chemotherapy, immunotherapy, or external beam radiation Appropriate encounter code, Z51.11, Z51.12, or Z51.0, is principal/first-listed, with the treated malignancy additional

Admission for insertion or implantation of radioactive elements, such as brachytherapy Malignancy is principal/first-listed; do not assign Z51.0 for this circumstance

Management of anemia associated with malignancy, with only anemia treated Malignancy first, followed by the appropriate anemia code, such as D63.0

Management of anemia due to an adverse effect of chemotherapy or immunotherapy, with only anemia treated Anemia first, followed by the appropriate neoplasm and adverse-effect codes

Management of dehydration due to malignancy, with only dehydration treated Dehydration first, followed by the malignancy

The contrast between malignancy-associated anemia and therapy-associated anemia is an important exam reasoning task. Establish the documented relationship and treatment purpose rather than selecting the condition that appears most severe. An encounter involving tumor removal followed by adjunct therapy also differs from an encounter chiefly for administering therapy; consult the specific provision.

Diabetes and hypertensive combinations

Section I.C.4.a classifies diabetes by type and documented cause. If type is not documented, the default is E11.-, type 2 diabetes. Do not use insulin treatment alone to infer type 1 diabetes, or disregard an established drug-induced or other secondary form. Verify the actual Index relationship before applying the with convention to a complication.

For type 2 diabetes routinely treated with insulin, Z79.4 , long term (current) use of insulin, identifies that long-term use. Temporary insulin to control blood glucose during an encounter does not establish long-term use. Missing type, complication specificity, and medication status are separate review questions.

Section I.C.9.a provides hypertension combination rules. Hypertension with specified heart disease and hypertension with chronic kidney disease have presumed relationships unless the documentation clearly states they are unrelated. Use the appropriate combination code and required additional codes. If both hypertensive heart disease and CKD are present, examine I13.- rather than separately assigning I11.- and I12.-.

For hypertension with stage 3b CKD, no heart disease, and no contrary documentation, I12.9 with N18.32 captures hypertensive CKD and its stage. The pairing does not require a query solely because the provider omitted the words due to. Actual conflicting documentation or missing stage may require clarification.

Acute respiratory failure and another acute condition

Section I.C.10.b permits acute or acute-and-chronic respiratory failure as principal when it meets the definition and the classification supports that selection. Chapter-specific sequencing directions, including obstetric, poisoning, HIV, and newborn rules, take precedence where applicable.

When respiratory failure and another acute condition coexist, the principal diagnosis depends on admission circumstances. Either may be selected under Section II.C only when they are equally responsible for admission and no chapter-specific rule directs sequencing. If that responsibility is unclear, query the provider. The treatment focus alone is not a universal tie-breaker, and respiratory failure that develops later does not automatically replace the admission diagnosis.

Acute-and-chronic respiratory failure also requires supported documentation of both components. Home oxygen use can prompt review but is not itself a provider diagnosis of chronic respiratory failure.

Drug events: distinguish proper use from improper use

Under Section I.C.19.e , the administration circumstances determine the drug-event pathway:

Event General assignment approach

Adverse effect of a correctly prescribed and properly administered drug Nature of adverse effect first, then the appropriate drug adverse-effect code

Poisoning , such as overdose, wrong drug, or wrong route Poisoning code first, then manifestations; identify the documented intent

Underdosing , taking less than prescribed or instructed Underdosing code cannot be principal/first-listed; report the associated condition and known intent/circumstances as applicable

Toxic effect of a harmful nonmedicinal substance Toxic-effect code first, followed by associated manifestations

An elevated drug-effect laboratory result alone does not distinguish poisoning from an adverse effect. Review the prescription, actual administration, provider diagnosis, and causal documentation. For an actively treated, documented adverse effect of correctly administered anticoagulants, T45.515A identifies the drug adverse effect after the code for its nature. The code's descriptor is anticoagulants, not all antithrombotic drugs.

Use the required seventh character according to treatment phase: A for active treatment, D for routine healing/recovery after active treatment, and S for sequela when applicable. It is not determined simply by the first visit or the hospital's inpatient label. Check the FY2027 classification for complete codes, inherited instructions, and category-specific requirements.