6-2 Blood Collection and Processing

Plasma is the liquid from blood that has been allowed to clot.

• True

• False

Standard policy is to draw blood from a vein above an intravenous line.

• True

• False

If plasma is to be used in a test, it should be removed from the cellular portion of blood as soon as possible after collection.

• True

• False

For chemistry analysis, blood must be free of hemolysis.

• True

• False

The red/gray stopper tube contains a polymer gel and a silica activator.

• True

• False

In the CLSI order of draw, the red-top clot tubes are drawn first.

• True

• False

Mistakes occurring when blood is drawn contibute to preanalytical error.

• True

• False

Which is true of hemolysis of red blood cells?

• It releases potassium into the plasma or serum.

• It can be caused by overcentrifugation.

• It can be caused by excess shaking of the blood sample.

• all of the above

How does the time of specimen collection affect certain tests?

• Glucose and cholesterol usually change after eating.

• Concentrations of iron are constant throughout the day.

• Triglycerides do not change after eating.

• Corticosteroids are not affected by the time of collection.

Which is true of plasma and/or serum?

• Serum contains all of the dissolved chemical constituents plus the coagulation proteins.

• Plasma contains all of the dissolved chemical constituents.

• Plasma is formed when a tube of blood is allowed to clot.

• none of the above