The proper order of draw for blood collection begins with the blood culture tube, according to The University of Utah Eccles Health Sciences Library. Types of tubes include the coagulation tube, the nonadditive tube and six different additive tubes. A particular order prevents cross-contamination of tube additives.
Six additive tubes are used in a particular order. First is the serum separator tube, which contains a clot activator and a gel separator. Next are the sodium heparin tube, the plasma separator tube, the ethylenediaminetetraacetic acid tube, the acid citrate dextrose tube, and finally the oxalate or fluoride tube, explains The University of Utah Eccles Health Sciences Library. Each of these additive tubes must be mixed thoroughly to provide accurate blood test results.
Typically, the tops of plastic vacutainer tubes used for storing drawn blood follow a color scheme, notes The University of Utah Eccles Health Sciences Library. The blood culture tube has a yellow or a yellow-black top, while the coagulation tube has a light blue top. The nonadditive tube has a red top, and the SST additive tube has a red-gray or a gold top. The sodium heparin tube has a dark green top, and the PST tube has a light green top. The EDTA tube has a lavender top, and the ACDA tube has a pale yellow top. The final additive tube, containing oxalate or fluoride, has a light gray top.