Quick Review Cards for Medical Laboratory Science

Phlebotomy Sources of Errorcontinued

ERROR POSSIBLE EFFECT

Short draws

Inadequate mixing of anticoagulant tube

Hemolysis from alcohol contamination, “milking”

site of capillary puncture, probing with needle,

vigorous shaking of tubes, exposure of samples to

extremes of temperature

Incorrect blood: anticoagulant ratio affects some results, e.g., coag tests.

Micro-clots, fibrin, platelet clumping can lead to erroneous results.

↑K+, Mg2+, LD, iron

Laboratory Operations Review 24