A
5200 Harry Hines Blvd.
,
Dallas
,
TX
75235
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General Information
Alias: PTT, aPTT
Performed: 24 hrs.
Turn Around Time: Med Emerg: 60 minutes; Routine: 4 hrs
CPT Codes: 85730
Performed By: Hematology
Notes:
When Hematocrit is >55%, original results that are abnormal must be corrected on patients greater than 4 months of age.
Test also performed by the Rapid Response Lab.
Clinical Utility:
Used to screen for abnormalities in the Intrinsic Coagulation Pathway. For monitoring anticoagulation therapy with PTT, therapeutic ranges are: Unfractionated heparin: 75-100 seconds; Argatroban: 75-100 seconds.
Unacceptable Conditions:
Clotted, severely hemolyzed, refrigerated, and/or on ice. In patient PTT specimens over 1 hour old will be rejected. Heparin (UFH) and IV fluids will prolong results. Specimens should not be drawn with heparinized syringe, through lines containing heparin/fluid, or during procedures using heparin (such as dialysis or apheresis). Collection through PICC lines and medi-ports are generally unacceptable due to insufficient flush and discard. If VAD collection is necessary, flush with 5mL of saline and then discard 6 times the volume of the line measured from collection port to catheter tip. Refrigerated or on ice.
PTT results on the ACL TOP are not affected by hemoglobin up to 400 mg/dL, bilirubin up to 14.9 mg/dL and triglycerides up to 877 mg/dL.
Components
Name |
Method |
Sex |
Age Range |
Ref. Range Low |
Ref. Range High |
Units |
PTT |
Clot based |
All |
All |
25.1 |
41.5 |
sec |
Specimen Requirements
Type |
Container |
Volume |
Units |
Collection / Delivery |
Storage / Transport |
Off Campus |
Blood |
Blue 3.2% Na Citrate, 3 ml |
Draw to fill line |
|
Deliver to Lab within 3 hours of collection |
Room Temperature |
Deliver to Logistics Hematology Lab via STAT courier. |