CPC cheat sheet

The ICD-10-CM Official Guidelines for Coding and Reporting are organized by chapter and take precedence over the Alphabetic Index and Tabular List when a conflict arises; the Tabular List takes precedence over the Index alone.

Convention symbols: [ ] encloses synonyms, alternative wording, or manifestations; ( ) encloses nonessential modifiers that do not affect code assignment; : indicates a code requires additional characters; } appears only in the Index and means the entry requires a 7th character.

"Code first" identifies an underlying condition that must be sequenced before the manifestation; "Use additional code" is instructional and does not govern sequencing; "Excludes1" means the two conditions cannot be coded together (not coded here), "Excludes2" means both may be reported when documented.

Sequencing is determined by the reason for the encounter (first-listed/principal diagnosis), not by severity or by the order conditions appear in the record; for outpatient records, the first-listed code is the condition chiefly responsible for the services provided.

Signs and symptoms that are routinely associated with a confirmed diagnosis are not coded separately; if no definitive diagnosis is documented, code the sign or symptom to the highest degree of certainty.

Acute and chronic forms of the same condition documented together generally require separate codes when the classification provides distinct subentries (for example, acute and chronic bronchitis); combination codes are used when a single code fully captures both elements.

Laterality, encounter type (initial, subsequent, sequela), and 7th-character extensions must be supported by documentation; unspecified codes are assigned only when the record lacks detail to support a more specific code.

Z codes are used for factors influencing health status and encounters for reasons other than disease; they may be first-listed when they represent the reason for the encounter, such as screening or status after completed treatment.

Diabetes mellitus: E08-E13 codes require an additional code for the type of diabetes only when using E08-E13 with insulin, oral hypoglycemics, or injectable non-insulin drugs; code also any associated complications, and diabetic manifestations are combined into a single code where available (e.g., E11.21 diabetic nephropathy).

Myocardial infarction: code the type (STEMI, NSTEMI) and site; a new MI within 4 weeks of a prior MI is coded as an acute MI, while an MI documented as old or healed without current symptoms is coded as a history of MI (I25.2).

Hypertension: I10 is used for essential hypertension without heart or kidney involvement; hypertension with heart disease requires I11.- codes, and hypertension with both heart and kidney disease uses I13.- with additional codes for heart failure and chronic kidney disease stage.

Asthma is classified by severity and control in J45.-; status asthmaticus is J45.901, and acute exacerbation is captured with the appropriate J45 code rather than a separate exacerbation code.

Fractures require codes for the specific site and laterality, fracture type, and a 7th character for encounter type (A initial, D subsequent with routine healing, G subsequent with delayed healing, K subsequent with nonunion, S sequela); the fracture code alone does not describe the external cause.

Chronic kidney disease codes N18.- require a stage (1 through 5 or end stage); stage 1 and 2 require documentation that the stage was established by a clinician, and dialysis status (Z99.2) is coded separately from the CKD stage.

Neoplasms: the primary site is coded first, followed by the secondary (metastatic) site; when the encounter is for treatment of the metastasis, the secondary site may be first-listed, and Z85.- history of malignant neoplasm codes are used after treatment is complete with no evidence of disease.

Sepsis and severe sepsis: A41.- is the code for sepsis due to a specified organism, with the systemic infection sequenced first; R65.20 (severe sepsis without shock) or R65.21 (severe sepsis with septic shock) is added when documented, and localized infections are coded additionally.

CPT® is divided into six sections: Evaluation and Management, Anesthesia, Surgery, Radiology, Pathology and Laboratory, and Medicine; Category II codes are supplemental tracking codes, and Category III codes are temporary emerging-technology codes with 4 digits and a trailing T.

The global surgical package includes the preoperative evaluation, the surgical procedure itself, and routine uncomplicated postoperative care; for major surgery the global period is 90 days, for minor surgery it is 0 or 10 days, and modifiers 24, 25, 57, 58, 78, and 79 govern services within that period.

Surgical modifier rules: modifier 50 is bilateral, 51 is multiple procedures, 58 is staged or related procedure during the postoperative period, 78 is an unplanned return to the operating room, 79 is an unrelated procedure during the postoperative period, and 62 is two surgeons.

Add-on codes (+) are never reported alone and are exempt from multiple procedure reduction; they must be reported with the primary procedure and are listed in the code descriptor with the primary code.

HCPCS Level II codes begin with a letter: A-codes for supplies, E-codes for durable medical equipment, J-codes for drugs and biologicals, L-codes for orthotics and prosthetics, and V-codes for vision; units for J-codes are based on the dosage descriptor (e.g., per 10 mg).

Evaluation and Management, radiology, and laboratory services are not subject to multiple procedure payment reduction the way surgical procedures are; the highest-valued procedure is reported at full value and subsequent procedures at the applicable reduced rate.

Modifier 59 and the X{EPSU} modifiers (XE, XS, XP, XU) identify distinct procedural services; XS is used for a separate structure, XE for a separate encounter, XP for a separate practitioner, and XU for an unusual non-overlapping service.

Anesthesia coding uses the base unit value of the procedure plus time units (one unit per 15 minutes of anesthesia time) plus qualifying circumstances; physical status modifiers P1-P6 describe the patient's condition and do not affect payment.

Office and outpatient E/M level selection (99202-99215) is based on either medical decision making or total time on the date of the encounter, not both; the level chosen must be supported by the documented elements.

Medical decision making has three elements: number and complexity of problems addressed, amount and/or complexity of data reviewed and analyzed, and risk of complications, morbidity, or mortality; the level is determined by the two elements with the highest level (or two of three for moderate).

Total time for E/M includes the time on the date of the encounter spent on the patient's care, including chart review, ordering tests, communicating with the patient and other providers, and documenting; it does not include separately reported services.

History and physical examination are no longer required to level office E/M codes, but documentation must support the problems addressed and the data reviewed, and the medically appropriate history and exam must still be performed and documented.

Prolonged services are reported with 99417 (office/outpatient, each 15 minutes beyond the maximum threshold) or with the applicable prolonged service code for other settings; time must exceed the highest-level threshold before the add-on is used.

Hospital inpatient and observation E/M codes (99221-99239) are selected by medical decision making or time; subsequent care codes require documentation of the patient's condition and the services provided.

Modifier 25 is appended to an E/M service when a significant, separately identifiable E/M is provided on the same day as a procedure; the E/M must be above and beyond the usual preoperative and postoperative work of the procedure.

Critical care (99291-99292) requires the patient to be critically ill or injured with a high probability of imminent deterioration; the first 30-74 minutes are reported with 99291, and each additional 30 minutes with 99292.

Facility and non-facility place-of-service codes affect payment: non-facility (office) rates include practice expense for supplies and staff, while facility rates apply when services are performed in a hospital outpatient department or ambulatory surgical center.

Ambulatory surgical center (ASC) services are reported with CPT® codes on the ASC-covered procedure list; the ASC facility fee is paid separately from the physician's professional fee, and the physician reports the procedure with the appropriate modifier for the site of service.

Place of service codes: 11 is office, 19 is off-campus outpatient hospital, 22 is on-campus outpatient hospital, 24 is ambulatory surgical center, and 21 is inpatient hospital; the POS reported must match where the service was actually furnished.

Same-day surgical services: when a procedure is performed and the patient is admitted, the physician reports the procedure code and the appropriate E/M code with modifier 57 if the decision for surgery was made that day.

Hospital outpatient services are reported with CPT® and HCPCS Level II codes and are subject to the outpatient prospective payment system (OPPS); the facility reports the procedure, and the professional component is reported by the physician with modifier 26.

The global surgical package does not apply to ASC facility fees the same way it applies to physician services; the ASC reports the procedure code and is paid a facility rate based on the ASC payment group.

Observation services are reported by the facility with HCPCS code G0378 per hour and G0379 for direct admission; physician observation E/M codes are 99218-99220 (initial) and 99224-99226 (subsequent).

The False Claims Act prohibits knowingly submitting false or fraudulent claims; the Anti-Kickback Statute prohibits remuneration for referrals of federally payable items or services, and the Physician Self-Referral (Stark) Law prohibits referrals of designated health services to entities with which the physician has a financial relationship, absent an exception.

The Health Insurance Portability and Accountability Act (HIPAA) Privacy and Security Rules govern protected health information; the minimum necessary standard applies to uses and disclosures, and the Security Rule covers administrative, physical, and technical safeguards.

Medical necessity requires that services be reasonable and necessary for the diagnosis or treatment of illness or injury; documentation must support the service, and the diagnosis must be linked to the procedure on the claim.

The Advance Beneficiary Notice of Noncoverage (ABN) is used for Medicare beneficiaries when a service may be denied as not medically necessary; a valid ABN must be signed before the service and retained, and the modifier GA indicates an ABN is on file.

National Correct Coding Initiative (NCCI) edits identify code pairs that should not be reported together; modifier 59 or the appropriate X modifier may be used only when the documentation supports a distinct service, and the edit is not bypassed automatically.

Payer requirements: Medicare Part B covers physician and outpatient services, Part A covers inpatient hospital services, and the Medicare Secondary Payer rules determine when Medicare pays secondary to another insurer, such as workers' compensation or group health coverage.

Claim forms: the CMS-1500 is used for physician and noninstitutional services, and the UB-04 is used for institutional claims; diagnosis codes on the CMS-1500 are reported in priority order with the first-listed diagnosis matching the reason for the service.

Audit and documentation requirements: the medical record must support the code reported, and the documentation must be legible, authenticated, and contemporaneous; copies of documentation must be retained per payer and state requirements (commonly 7 years under Medicare).