4A1ZXKZMonitoring of Temperature, External Approach

Measurement and Monitoring›Physiological Systems›Monitoring

Billable / Specific Code

ICD-10-PCS 4A1ZXKZ

CMS Source: FY 2026 ICD-10-PCS dataset. Effective Oct 1, 2025 – Sep 30, 2026.

4A1ZXKZ is a billable ICD-10-PCS procedure code for Monitoring of Temperature, External Approach. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). The root operation Monitoring involves determining the level of a physiological or physical function repetitively over a period of time.

Code Identity

ICD-10-PCS Code

4A1ZXKZ

Billable Status

Yes — Valid for Submission

Code Describes

Monitoring of Temperature, External Approach

Parent Code

4A1

Short Description

Monitoring of Temperature, External Approach

PCS Table Breakdown

Each ICD-10-PCS code is built from seven characters, each an axis of the procedure. Hover or tap the icons for the official CMS definitions.

Position	Designation	Value	Meaning
1	Section	4	Measurement and Monitoring
2	Body System	A	Physiological Systems
3	Operation	1	Monitoring
4	BodySystem	Z	None
5	Approach	X	External
6	Function/Device	K	Temperature
7	Qualifier	Z	No Qualifier

Convert to ICD-9-PCS

Closest ICD-9-PCS equivalents for 4A1ZXKZ under the General Equivalence Mappings.

89.39

Approximate match.

Similar Procedure Codes

Questions About 4A1ZXKZ

Is 4A1ZXKZ a billable code?

Yes. 4A1ZXKZ is a complete seven-character ICD-10-PCS code, specific enough to report Monitoring of Temperature, External Approach on inpatient claims from October 1, 2025 through September 30, 2026.

What do the characters in 4A1ZXKZ mean?

4A1ZXKZ breaks down character by character: the 1st character 4 is the Section (Measurement and Monitoring); the 2nd character A is the Body System (Physiological Systems); the 3rd character 1 is the Operation (Monitoring); the 4th character Z is the BodySystem (None); the 5th character X is the Approach (External); the 6th character K is the Function/Device (Temperature); the 7th character Z is the Qualifier (No Qualifier).

What is the ICD-9-PCS equivalent of 4A1ZXKZ?

Under the General Equivalence Mappings, Monitoring of Temperature, External Approach crosswalks to ICD-9-PCS 89.39. The mapping is approximate, so confirm it fits the documentation.