Prolonged Protime Profile
Use
Determine the cause of an extended prothrombin time
Special Instructions
Ensure proper specimen collection by adhering to the specific guidelines for citrated plasma samples. Use double centrifugation and maintain precise blood to anticoagulant ratio by filling evacuated collection tubes to completion. Immediate mixing by gentle inversion is critical to avoid clotting. A discard tube is necessary when using a butterfly blood collection device. Use Labcorp PP transpak frozen purple tubes with screw caps for transport and ensure samples remain frozen until testing.
Limitations
The test's accuracy and reliability depend on proper specimen collection and handling. Underfilled or improperly mixed tubes may lead to incorrect results. Variations in sodium citrate concentration can affect test outcomes, so adherence to guidelines is crucial. The presence of lupus anticoagulant or other interfering substances might affect the dilute prothrombin time measurement. The test does not detect all possible coagulation disorders and should be considered in conjunction with other clinical and laboratory findings for comprehensive assessment of bleeding disorders.
Methodology
Other
Biomarkers
LOINC Codes
- 75508-2
- 75884-7
- 3255-7
- 3289-6
- 3193-0
- 3198-9
- 3218-5
Result Turnaround Time
2-3 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
3 mL
Minimum Volume
2 mL
Container
Blue-top (sodium citrate) tubes
Collection Instructions
Citrated plasma samples should be collected by double centrifugation. Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate. Evacuated collection tubes must be filled to completion to ensure a proper blood to anticoagulant ratio. The sample should be mixed immediately by gentle inversion at least six times to ensure adequate mixing of the anticoagulant with the blood. A discard tube is not required prior to collection of coagulation samples, except when using a winged blood collection device (ie, "butterfly"), in which case a discard tube should be used. When noncitrate tubes are collected for other tests, collect sterile and nonadditive (red-top) tubes prior to citrate (blue-top) tubes. Any tube containing an alternate anticoagulant should be collected after the blue-top tube. Gel-barrier tubes and serum tubes with clot initiators should also be collected after the citrate tubes. Centrifuge for 10 minutes and carefully remove 2/3 of the plasma using a plastic transfer pipette, being careful not to disturb the cells. Deliver to a plastic transport tube, cap, and recentrifuge for 10 minutes. Use a second plastic pipette to remove the plasma, staying clear of the platelets at the bottom of the tube. Transfer the plasma into a Labcorp PP transpak frozen purple tube with screw cap (Labcorp No. 49482). Freeze immediately and maintain frozen until tested.
Storage Instructions
Freeze.
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