Mary Jo Bowie MS, BS, AAS, RHIA, RHIT

Diagnostic Coding Guidelines CHAPTER 5 Diagnostic Coding Guidelines

Diagnostic Coding Guidelines The ICD-10-CM Official Guidelines for Coding and Reporting were developed by: Centers for Medicare and Medicaid Services National Center for Health Statistics

Cooperating Parties for ICD-10-CM The following organizations, known as the Cooperating Parties for ICD-10-CM, have approved the guidelines: American Hospital Association American Health Information Management Association Centers for Medicare and Medicaid Services National Center for Health Statistics

Guidelines Four Sections There are four sections to the guidelines: Section I—Conventions, General Coding Guidelines, and Chapter-Specific Guidelines Section II—Selection of Principal Diagnosis Section III—Reporting Additional Diagnoses Section IV—Diagnostic Coding and Reporting Guidelines for Outpatient Services

Section I Section I—Conventions, General Coding Guidelines, and Chapter-Specific Guidelines This section includes guidelines that address the structure and conventions and general guidelines and chapter-specific guidelines.

Section II Section II—Selection of Principal Diagnosis This section includes the guidelines for the selection of the principal diagnosis for nonoutpatient settings.

Definition of Nonoutpatient Settings Nonoutpatient settings include: Acute care Short-term care Long-term care Psychiatric hospitals Home health agencies Rehab facilities Nursing homes and the like

Section III—Reporting Additional Diagnoses This section includes the reporting of additional diagnoses that affect patient care in nonoutpatient settings.

Section IV Section IV—Diagnostic Coding and Reporting Guidelines for Outpatient Services This section contains the guidelines for outpatient coding that includes both outpatient hospital services and provider- based office visits.

General Coding Guidelines Diagnosis codes are to be used and reported at their highest number of characters. Codes that describe symptoms and signs are acceptable for coding when a definitive diagnosis has not been established. Signs and symptoms that are associated with a disease should not be reported.

General Coding Guidelines (cont.) Additional signs and symptoms that may not be associated routinely with a disease process should be coded when present. Multiple codes may be needed. If the same condition is described as both acute (subacute) and chronic and separate subentries exist, code both and sequence the acute condition first.

General Coding Guidelines (cont.) A sequela (late effect) effect is the residual effect after the acute phase of an illness or injury. Each unique ICD-10-CM diagnosis code may be reported only once for an encounter. For bilateral sites, the final character of codes in the ICD-10-CM indicates laterality.

General Coding Guidelines (cont.) Principal Diagnosis A condition established after study to be chiefly responsible for occasioning the admission of the patient to the hospital for care.

General Coding Guidelines (cont.) When two or more interrelated conditions potentially meet the definition of principal diagnosis, either condition may be sequenced first. When two or more contrasting/comparative diagnoses are documented as either/or they are coded as if confirmed and the diagnoses are sequenced according to the circumstances of the admission.

General Coding Guidelines (cont.) When a symptom(s) is followed by contrasting/comparative diagnoses, the symptom code is sequenced first. Sequence as the principal diagnosis the condition, which after study occasioned the admission to the hospital, even though treatment may not have been carried out due to unforeseen circumstances.

General Coding Guidelines (cont.) When the admission is for treatment of a complication resulting from surgery or other medical care, the complication code is sequenced as the principal diagnosis. If the diagnosis is qualified indicating uncertainty, code the condition as if it existed or was established. This is for inpatient cases only.

Secondary Diagnoses Guideline Secondary diagnoses are 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 that relate to an earlier episode which have no bearing on the current hospital stay are to be excluded.

Outpatient Guidelines In the outpatient setting, the term “first-listed diagnosis” is used in lieu of principal diagnosis. List first the code for the diagnosis, condition, problem, or other reason for the encounter/visit shown in the medical record to be chiefly responsible for the services provided. Do not code uncertain diagnoses.

Outpatient Coding Guidelines Chronic diseases treated on an ongoing basis may be coded and reported as many times as the patient receives treatment and care for the condition. Code all documented conditions that coexist at the time of the encounter/visit, and require or affect patient care, treatment, or management.

Outpatient Coding Guidelines For patients receiving diagnostic or therapeutic services only during the encounter/visit, sequence first the diagnosis, condition or problem, or other reason for the encounter/visit shown in the medical record to be chiefly responsible for the outpatient service. For ambulatory surgery, code the diagnosis for which the surgery was performed.