Summary & Overview
CPT 85170: Quantification of Serum and Red Cells Retained in a Clot
CPT code 85170 represents a laboratory hematology procedure in which a technician quantifies the amounts of serum and red blood cells retained within a forming clot. This specialized analytic test is relevant for clinical laboratories that perform coagulation and clot composition assessments, and it has implications for patient diagnosis, transfusion decisions, and quality control in hematology testing nationally.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find clinical context for the test, typical sites of service, and an overview of the kinds of benchmarks and policy considerations that affect coverage and billing for specialized lab procedures. The analysis highlights coding precision, common modifier usage provided in the input, and how that intersects with payer adjudication practices.
This publication provides: a concise clinical description of the test procedure and its diagnostic role; payer coverage landscape and common billing practices; and notes on documentation and billing elements that influence reimbursement. Data not available in the input are explicitly noted where applicable.
Billing Code Overview
CPT code 85170 describes a laboratory evaluation in which a lab analyst measures the amounts of serum and red blood cells retained in a forming clot from a blood specimen. This procedure is a laboratory hematology service focused on clot composition analysis.
Service type: Laboratory test / Hematology analysis
Typical site of service: Clinical laboratory or hospital laboratory
Data not available in the input for associated taxonomies, ICD-10 diagnoses, and related codes.
Clinical & Coding Specifications
Clinical Context
A typical patient is an adult undergoing laboratory evaluation for hemostatic function after abnormal bleeding, bruising, or as part of preoperative workup where clot formation characteristics are clinically relevant. A phlebotomist collects a blood specimen and sends it to the clinical laboratory. A medical laboratory scientist or hematology technologist performs a clot retention assessment to determine the amount of serum and red blood cells retained within a forming clot, which can affect interpretation of platelet counts and coagulation assays. The workflow includes specimen accessioning, inspection for clot formation, performance of the clot retention measurement per laboratory protocol, documentation of results in the laboratory information system, and communication of clinically significant findings to the ordering clinician. Typical sites of service include hospital clinical laboratories, independent outpatient reference laboratories, and ambulatory surgery center laboratories where preoperative testing is performed.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
00 | Default CMS indicator (no modifier) | When no other procedural modifier applies; used in billing systems as a neutral code. |
11 | Office or other outpatient visit (historic use as primary) |