Routine Blood Collections: flashcards

All cards

CLSI order of draw

1 blood culture · 2 citrate (blue) · 3 serum w/ clot activator+gel (red/gold) · 4 heparin (green) · 5 EDTA (lavender) · 6 fluoride-oxalate (gray).

The CLSI exception

Only blood culture tubes, glass nonadditive serum tubes, or plastic serum tubes WITHOUT clot activator may precede the coagulation tube.

Why the order exists

Additive carryover from one tube alters the next test. Not vacuum, not volume.

EDTA before citrate

Both bind calcium. EDTA carryover ruins the coagulation result.

Tourniquet limit

Release before withdrawing the needle, and always before 2 minutes.

Anchoring

Thumb BELOW the site. Enter at 30 degrees or less.

Inversion counts

NOT published by CLSI or WHO. Follow the tube manufacturer (NHA task 3N) and your local lab.

Colour coding

A convention, not a standard. Varies by manufacturer — verify with your lab.