Physiological Systems and Anatomical Regions (3E) ICD-10-PCS
The 3E body system covers Administration procedures on physiological systems and anatomical regions, with 1,149 ICD-10-PCS codes across 2 root operations, 1,147 of them billable in fiscal year 2027. Each root operation defines a distinct procedural objective, and the info icons show the official definition with a preview of the codes inside.
Root Operations in This Body System 2 operations · 1,149 codes
| Chars 1–3 | Root Operation | Codes | Billable |
|---|---|---|---|
| 3E0 | IntroductionPutting in or on a therapeutic, diagnostic, nutritional, physiological or prophylactic substance except blood or blood products | 1,067 | 1,066 |
| 3E1 | IrrigationPutting in or on a cleansing substance | 82 | 81 |
The info icon shows the official root operation definition and previews the codes in that range.
About the 3E Body System
These codes describe putting substances in or on body regions such as skin and mucous membranes, veins, and the eye.
Introduction covers therapeutic, diagnostic, nutritional, physiological, and preventive substances other than blood or blood products. The procedures include chemotherapy, antibiotic administration, and regional anesthesia, which numbs an area. Irrigation puts in or on a cleansing substance. The body system or region value identifies the site, with choices including the spinal canal and joints.
FY 2027 changes: The FY 2027 ICD-10-PCS update, effective October 1, 2026, added 4 codes in this body system. Table with changes: 3E0 Introduction.
Questions About This Page
How many codes are in the 3E body system?
The 3E body system contains 1,149 ICD-10-PCS codes in FY 2027, organized into 2 root operations. 1,147 of them are billable on inpatient claims.
What is a root operation?
The root operation is the third character of every ICD-10-PCS code and names the objective of the procedure. Drainage takes fluid out, Excision cuts out a portion of a body part, and Resection removes all of one. Picking the right root operation is the central skill of PCS coding, so each one above carries its official CMS definition.
Related References
Source: CMS FY 2027 ICD-10-PCS order file and code tables, effective October 1, 2026 through September 30, 2027.
