STAT 1 hour, Routine 4 hours
Test Updated:
Activated Partial Thromboplastin Time
APTT
PTT
PARTIAL THROMBOPLASTIN TIME
aPTT
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Test Overview
Photo-optical clot determination
Evaluation of intrinsic coagulation system, aid in screening for presence of classical hemophilia A and B, Christmas disease, congenital deficiencies of factors II, V, VIII, IX, X, XI and XII, dysfibrinogenemia, disseminated intravascular coagulation, liver failure, congenital hypofibrinogenemia, vitamin K deficiency, congenital deficiency of Fitzgerald factor and prekallikrein.
21 - 29 seconds. If the aPTT is being used to monitor heparin, the current applicable heparin nomogram should be used.
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Specimen Requirements
Collect specimen in a blue top (citrate 3.2%) tube. Mix by inversion. Specimen should arrive at lab within 3 hours of collection; transport at room temperature. Collection of the blood through lines that have been previously flushed with heparin should be avoided. If the blood must be drawn through a VAD (vascular access device), the line should be flushed with 5 mL of saline and the first 5 mL of blood or six dead space volumes of the VAD discarded.
Collect specimen in a blue top (citrate 3.2%) tube. Mix by inversion. Specimen should arrive at lab within 3 hours of collection; transport at room temperature. Alternatively, centrifuge, aliquot plasma into a plastic tube, and freeze the specimen within 4 hours of collection. Transport frozen specimen on dry ice. Collection of the blood through lines that have been previously flushed with heparin should be avoided. If the blood must be drawn through a VAD (vascular access device), the line should be flushed with 5 mL of saline and the first 5 mL of blood or six dead space volumes of the VAD discarded.
