D-Dimer, Plasma

DDIQ - NOCO

1.0 mL plasma from Blue Top (3.2% Na Citrate)

Full blue top tube or 1.0 mL plasma frozen

• It is imperative that the tube be completely filled to frosted line. The ratio of blood to anticoagulant is critical for valid coagulation results. If obtaining blood with a syringe, fill the light blue-top (sodium citrate) tube first.
• If patient is on heparin, specimen must be centrifuged and separated within 1 hour of draw.
• Heparin contaminated tube is not acceptable.
• Keep specimen anaerobic.
• Patients with an extremely high hematocrit may require special tubes before obtaining blood for coagulation testing. Please contact the lab for further information.
• If testing will not be completed within 4 hours, spin down, remove plasma, and spin plasma again, and send specimen frozen in plastic vial.

Specimen Type	Temperature	Time
Whole blood Na Cit  on heparin	Ambient	1 hour
Whole blood Na Cit (unopen/unspun)	Ambient	4 hours
Plasma Na Cit (unopen/spun)	Ambient	4 hours
Plasma Na Cit double spun and separated	Frozen -20 C	2 weeks

Clotted Serum received instead of Sodium Citrate plasma
Specimen past stability
Frozen plasma received thawed
Underfilled or Overfilled, blood/anticoagulant ratio must be 9/1; Specimens must be between 90% -110% full
Collected in a 3.8% Sodium Citrate tube instead of 3.2% Sodium Citrate tube
Drawn in outdated/expired tube
Hemolyzed, icteric, or lipemic sample

Monday through Sunday; Continuously

Same day

0.27 - 0.49 ug/mL

The determination of D-Dimer is becoming a widespread tool for diagnosing thrombosis and monitoring thrombolytic therapy.

Elevated levels of D-Dimer are found in clinical conditions such as deep vein thrombosis (DVT, pulmonary embolism (PE) and disseminated intravascular coagulation (DIC). D-Dimer levels also rise during the normal pregnancy, but very high levels are associated with complications. A negative D-Dimer result when combined with a clinical assessment of low pretest probability has been shown to have a high negative predictive value for DVT or PE. D-Dimer results in human citrated plasma from IL Coagulation systems in conjunction with a clinical pretest probability (PTP) assessment model can exclude venous thromboembolism in outpatients suspected of deep venous thrombosis and pulmonary embolism.

While a positive D-Dimer alone is not diagnostic of DVT or PE, a negative D-Dimer can be used to exclude the diagnosis of venous thrombosis. There are a number of articles available that discuss the choice of cut-off value for ruling out venous thrombosis.