ASCP Patient Identification and Specimen Labeling Flashcards

Which of the following is an example of a pre-analytical error?

Answer: Collecting a specimen from the wrong patient

Pre-analytical errors occur before testing and include patient misidentification, improper collection technique, and mislabeling.

Hemolysis in a specimen is MOST likely caused by:

Answer: Forcing blood through a needle that is too small

Using a small-gauge needle or forcing blood through it creates shear forces that rupture red blood cells, causing hemolysis.

Which analyte is MOST significantly affected by hemolysis, producing a falsely elevated result?

Answer: Potassium

Hemolysis releases intracellular potassium from red blood cells into the serum, falsely elevating potassium levels.

Prolonged tourniquet application (greater than one minute) causes which pre-analytical error?

Answer: Hemoconcentration with falsely elevated proteins and cells

Prolonged tourniquet use causes hemoconcentration by restricting fluid movement, falsely elevating proteins, cells, and other analytes.

Drawing blood from an arm with a running IV in the same vein will MOST likely cause:

Answer: Falsely decreased analyte concentrations due to dilution with IV fluid

IV fluids contaminate the blood sample and dilute its components, causing falsely low results for most analytes.

Which specimen requires immediate transport on ice after collection?

Answer: Arterial blood gas specimen

Arterial blood gas specimens must be transported on ice immediately to stop cellular metabolism from altering pH, pCO2, and pO2 values.