Testing Algorithm Delineates situation(s) when tests are added to the initial order. This includes reflex and additional tests.
Initial testing includes: prothrombin time (PT); activated partial thromboplastin time (APTT); dilute Russells viper venom time (DRVVT); thrombin time (bovine); fibrinogen; D-dimer; soluble fibrin monomer; antithrombin activity; protein C activity; protein S antigen, free; prothrombin G20210A mutation; activated protein resistance V; and, if appropriate, special coagulation interpretation.
If PT is > or =14 seconds, PT mix will be performed.
If APTT is >36 seconds, APTT mix will be performed.
If APTT mix is >36 seconds with no evidence of heparin in samples, platelet neutralization procedure will be performed.
If DRVVT ratio is > or =1.2, DRVVT mix and DRVVT confirmation will be performed.
If thrombin time is >23 seconds, reptilase time will be performed.
If protein S antigen, free is <65% for males and females > or =50 years of age and <50% for females <50 years of age, protein S antigen, total will be performed.
If protein C activity is <70% with no evidence for an acquired decrease in protein C activity, protein C antigen may be performed.
If antithrombin activity is <80% with no evidence of an acquired decrease in antithrombin activity, antithrombin antigen will be performed.
If activated protein C resistance (APC) ratio is <2.3 or baseline APC APTT is prolonged, factor V leiden (R506Q) mutation analysis will be performed.
If appropriate, protein S activity, plasminogen, coagulation factor assays, or Staclot LA will be performed at an additional charge to clarify significant abnormalities in the screening clotting times.
If factor VIII result is <55%, the factor VIII inhibitor screen may be performed along with the Bethesda titering assay, if inhibitor screen is positive.
See Thrombophilia Profile algorithm in Special Instructions.
Specimen Type Describes the specimen type needed for testing
Plasma Na Cit
Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
See Coagulation Studies in Special Instructions.
1. Coagulation Patient Information Sheet (T675) in Special Instructions
2. New York Clients-Informed consent is required. Please document on the request form or electronic order that a copy is on file. An Informed Consent for Genetic Testing (Supply T576) is available in Special Instructions.
3. If not ordering electronically, complete, print, and send a Coagulation Test Request Form (T753) with the specimen (http://www.mayomedicallaboratories.com/it-mmfiles/coagulation-test-request-form.pdf)
Blood and plasma are required.
Specimen Type: Whole blood
Preferred: Yellow top (ACD)
Acceptable: EDTA, sodium citrate
Specimen Volume: 6 mL
1. Invert several times to mix blood.
2. Do not transfer blood to other containers.
3. Label specimen as whole blood.
Specimen Type: Platelet-poor plasma
Collection Container/Tube: Light-blue top (citrate)
Submission Container/Tube: Plastic vials
Specimen Volume: 6 mL in 6 plastic vials each containing 1 mL
1. Specimen must be drawn prior to factor replacement therapy.
2. Spin down, remove plasma, and spin plasma again.
3. Freeze specimens immediately at < or =-40 degrees C, if possible.
4. Label specimens as plasma.
5. Send specimens in the same shipping container.
1. Double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results.
2. Patient should not be receiving Coumadin or heparin.
3. If priority specimen, mark request form, give reason, and request a call-back.
Specimen Minimum Volume Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
Whole Blood: 3 mL/Plasma: 5 mL in 5 plastic vials each containing 1 mL
Mild OK; Gross reject
Mild OK; Gross reject
Mild OK; Gross reject
Green top (heparin) tube
Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
|Plasma Na Cit||Frozen||14 days|
|Whole blood||Ambient (preferred)||7 days|