Chapter 3 — Phlebotomy / Specimen Collection

Two patient identifiers

Use information such as full name and date of birth before specimen collection

Venipuncture

Needle puncture of a vein to obtain blood

Venipuncture needle angle

15 to 30 degrees

CBC

Lavender tube

Lavender tube additive

EDTA

PT/INR

Light blue tube

Blood cultures

Draw before other tubes when ordered

Order of draw

Blood cultures → light blue → serum → green → lavender → gray

Hemolysis

Destruction or rupture of red blood cells

Vigorous tube shaking

Can cause hemolysis

Proper tube mixing

Gently invert the tube

Tourniquet

Helps veins become more prominent for venipuncture

Specimen labeling

Label immediately after collection in the presence of the patient

Chain of custody

Documents possession and handling of a legal specimen

Drug and alcohol testing

Common reason for chain-of-custody documentation

24-hour urine collection

Collect all urine during the specified 24-hour period

24-hour urine volume

Document the total volume collected

Creatinine clearance

Often uses a 24-hour urine collection to evaluate kidney function

Stool specimen

Should not be contaminated by urine or toilet water

Capillary puncture

Warm the site to increase blood flow

CLIA-waived test

Simple laboratory test with a low risk of error

Rapid strep test

Common example of a CLIA-waived test