Specimen HandlingQuestion 77 of 100
A serum tube is centrifuged five minutes after collection and fibrin strands appear in the serum. What went wrong?
a.The tube was centrifuged at too low a speed
b.The serum was exposed to light
c.The tube contained too much clot activator
d.The specimen was spun before the clot had fully formed
Explanation
A plain or gel serum tube needs roughly 30 minutes at room temperature to clot completely before centrifugation, and spinning early leaves fibrin that clogs analyzers and skews results. Speed affects separation quality but does not create fibrin. Clot activator quantity is fixed by the manufacturer, and light exposure affects photosensitive analytes rather than clot formation.
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