Physiological Devices (4B) ICD-10-PCS
The 4B body system covers Measurement and Monitoring procedures on physiological devices, with 8 ICD-10-PCS codes across 1 root operations, 7 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 1 operations · 8 codes
| Chars 1–3 | Root Operation | Codes | Billable |
|---|---|---|---|
| 4B0 | MeasurementDetermining the level of a physiological or physical function at a point in time | 8 | 7 |
The info icon shows the official root operation definition and previews the codes in that range.
About the 4B Body System
These codes cover measurements of nervous system, heart, lung, and musculoskeletal functions, including checks of physiological devices.
The Measurement table records a function’s level at a point in time. It includes checks of pacemakers and defibrillators, peripheral nerve monitoring, and pulmonary function tests. The fourth character identifies Central Nervous, Peripheral Nervous, Cardiac, Respiratory, or Musculoskeletal.
Questions About This Page
How many codes are in the 4B body system?
The 4B body system contains 8 ICD-10-PCS codes in FY 2027, organized into 1 root operations. 7 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.
