What is the recommended order of draw when multiple tubes are collected?

What is the recommended order of draw when multiple tubes are collected?

• A. Draw order is not important; any tube can be filled first
• B. Use the order of draw recommended by the manufacturer only
• C. Follow the standard order of draw: blood culture, light blue, red or SST, green, lavender, gray
• D. Use the order of draw based on the phlebotomist's preference

Answer: (C)

The concept being tested is why a standard order of draw is used during venipuncture. Following a set sequence prevents additives in one tube from carryover contaminating the next, which could skew test results. Blood culture tubes are drawn first to minimize skin flora contamination of cultures. Next, the light blue tube (citrate) is drawn to preserve coagulation tests without carryover that could affect results. Then the red or SST tube is used to collect serum without additive interference, followed by green (heparin) for chemistry, lavender (EDTA) for hematology, and finally gray (pyridox inhibitors) for glucose testing. This order is designed to maintain sample integrity across common tests and reduce the risk of additive contamination affecting subsequent specimens. The other options don’t fit because they ignore the need to minimize cross-contamination and to protect test accuracy, or they rely on personal preference or manufacturer notes alone rather than the standard sequence used in most labs.

The concept being tested is why a standard order of draw is used during venipuncture. Following a set sequence prevents additives in one tube from carryover contaminating the next, which could skew test results. Blood culture tubes are drawn first to minimize skin flora contamination of cultures. Next, the light blue tube (citrate) is drawn to preserve coagulation tests without carryover that could affect results. Then the red or SST tube is used to collect serum without additive interference, followed by green (heparin) for chemistry, lavender (EDTA) for hematology, and finally gray (pyridox inhibitors) for glucose testing. This order is designed to maintain sample integrity across common tests and reduce the risk of additive contamination affecting subsequent specimens.

The other options don’t fit because they ignore the need to minimize cross-contamination and to protect test accuracy, or they rely on personal preference or manufacturer notes alone rather than the standard sequence used in most labs.