Justin successfully completed his first draw. The order was for a PT and PTT. Justin had the right patient, the right test, the right tube, and the right time. He collected the sample in a light blue top tube- he filled the tube to the middle and gently rotated the tube 5-10 times, to mix the sample with the additive. What (if anything) did Justin do wrong?
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BJustin did not rotate the tube enough- the sample will clot.
CJustin did not fill the tube completely.
DJustin is correct.
✓ Correct answer: C. Justin did not fill the tube completely.Justin forgot that a sample collected in a light blue top tube must completely fill the tube. Light blue top tubes contain the additive sodium citrate, in either 3.2% or 3.8% solution (determined by laboratory policy); since the mixing ratio is nine parts blood to one part citrate, most clinical laboratories will reject light blue top tubes that are not completely filled.
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