A phlebotomist must collect a blood culture set, a PT/INR, a basic metabolic panel on a gel serum tube, and a CBC. Which collection sequence follows the standard order of draw?
- ABlood culture, light blue, gel serum tube, lavenderCorrect
- BLight blue, blood culture, lavender, gel serum tube
- CGel serum tube, blood culture, light blue, lavender
- DLavender, light blue, blood culture, gel serum tube
Why: The standard order of draw is blood culture (sterile) first, then the light blue sodium citrate coagulation tube, then serum tubes with or without gel, then heparin, then EDTA, then glycolytic inhibitor tubes. Drawing the blood culture first protects it from skin-flora contamination introduced by non-sterile tube handling. Every other sequence listed allows additive carryover into a tube where that additive causes error, most notably EDTA carried into a chemistry or coagulation tube.CLSI GP41

