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Insufficient volume

  • Insufficient blood volume (short draws) within a collection tube containing anticoagulant will result in an incorrect ratio of blood to anticoagulant, and yield incorrect test results.
  • Short draws can be caused by:
  • A vein collapsing during phlebotomy.
  • The needle coming out of the vein before the collection tube is full.
  • Loss of collection tube vacuum before the tube is full. (Always keep extra tubes on hand.)