The PFA-100 (Platelet Function Assay or Platelet Function AnalyserBurket's Oral Medicine, 12e. Edition. Edited by Michael Glick. PMPH-USA, 2015
) is a

platelet Platelets, also called thrombocytes (from Greek θρόμβος, "clot" and κύτος, "cell"), are a component of blood whose function (along with the coagulation factors) is to react to bleeding from blood vessel injury by clumping, thereby ini ...

function analyser that aspirates blood

in vitro ''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in biology an ...

from a blood specimen into disposable test cartridges through a microscopic aperture cut into a biologically active Biological membrane, membrane at the end of a capillary. The membrane of the cartridges are coated with collagen and adenosine diphosphate (ADP) or collagen and epinephrine inducing a platelet plug to form which closes the aperture. The PFA test result is dependent on platelet function, plasma von Willebrand Factor level, platelet number, and (to some extent) the hematocrit (that is, the percent composition of red blood cells in the sample). The PFA test is initially performed with the Collagen/Epinepherine membrane. A normal Col/Epi closure time (<180 seconds) excludes the presence of a significant platelet function defect. If the Col/Epi closure time is prolonged (>180 seconds), the Col/ADP test is automatically performed. If the Col/ADP result is normal (<120 seconds), aspirin-induced platelet dysfunction is most likely. Prolongation of both test results (Col/Epi >180 seconds, Col/ADP >120 seconds) may indicate the following; * Anemia (hematocrit <0.28) * Thrombocytopenia (platelet count < 100 x 10/L) * A significant platelet function defect other than aspirin Once anemia and thrombocytopenia have been excluded, further evaluation to exclude von Willebrand disease and inherited/acquired platelet dysfunction can be made.

References

External links

Practical Haemostasis
Medical testing equipment {{biochem-stub