Veripath Test Directory

Epic Test Name EXTEM
Description EXTEM assay is a semi-quantitative assay used to monitor whole blood coagulation process via the extrinsic pathway in citrated whole blood specimens. The assay is performed on ROTEM Delta analyzer. There is an automatic calculation and documentation of the Clotting Time (CT), rate of Clot Formation (CFT and alpha angle), Clot Firmness (A20/MCF) and clot lysis (ML)
Specimen Requirements 
Container Light blue (3.2 % sodium citrate) collection tube
Specimen Type Blood
Preferred Collection Volume 3 mL
Minimum Collection Volume 2 mL
Collection Instructions When drawing specimens for coagulation testing, always draw a "pilot" tube (7-10ml plain red top tube), completely filled. This removes tissue fluid contamination. Samples should be obtained from peripheral vein whenever possible. If drawn from indwelling catheter, the line should be flushed with 15mL of saline. After irrigation, a "pilot" tube should be drawn and discarded.
Specimen Handling In-house patients, transport at room temperature.
Outside clients, follow collection instructions and the steps below:
1. Specimen must remain at room temperature.
2. Specimen must arrive withing 1 hour after collection.
Rejection Criteria Hemolysis, clotted, short sample, >4 hours old, frozen or centrifuged
Methodology Rotational thromboelastometry
Reference Range CT(43-66 second ); A20 (55-70mm); MCF(57-71); ML(<3%)
CPT Code(s) 85396
Department Hemostasis/Coagulation
Contact Information Hemostasis Lab; 214-633-4959 Customer Service: 214-633-0400, Toll Free 1-877-887-8136
Turn Around Time4 hours (24 hours- Outside clients)
Performed Sunday-Saturday
Performed by Hemostasis Lab
Updated/Reviewed 07/25/2016