tourniquet

Medical term Routine Blood Collections

Band tied 7 to 10 cm (3 to 4 in, about 4 to 5 finger widths) above the site to slow venous return so veins fill; release within 1 minute.

Sources

• Nikolac N, Supak-Smolcic V, Simundic AM, Celap I. Croatian Society of Medical Biochemistry and Laboratory Medicine: national recommendations for venous blood sampling (based on CLSI H3-A6). Biochem Med 2013;23(3):242-254 (PMC3900082) · Biochemia Medica via PubMed Central
• Chang J, et al. Standards and Practice Guidelines for Venous Blood Collection: Consensus Recommendations from the Korean Society for Laboratory Medicine. Ann Lab Med 2025;45(4):343-357 (PMC12187494) · Annals of Laboratory Medicine via PubMed Central
• WHO Guidelines on Drawing Blood: Best Practices in Phlebotomy (2010); official WHO IRIS PDF, also published as NCBI Bookshelf NBK138650 · World Health Organization

Free practice questions that use tourniquet

• Routine Blood Collections, question 8The lab rejects a hemolyzed light green-top (lithium heparin) tube. Which handling step at collection most likely caused the hemolysis?
• Special Collections, question 3A donor's blood flow is well established 40 seconds after the needle enters the vein, with the blood pressure cuff still inflated. What…

Related terms

• systemic circulationBlood flow from the left ventricle through the arteries to the body's tissues and back through the veins to…
• systolic pressureThe upper blood pressure number: the peak pressure in the arteries while the ventricles contract.
• thrombinClotting enzyme that turns fibrinogen into fibrin. Orange-top tubes use a thrombin-based clot activator to…
• thrombusA blood clot formed inside a vessel. A thrombosed vein feels hard or cordlike and is not used for…
• tube holderPlastic barrel that holds the tube and shields the hand. It stays attached to the used needle and is…
• vasovagal reactionReflex slowing of the heart and drop in blood pressure: pale, sweaty, nauseated or dizzy, sometimes…
• veinA vessel that carries blood back toward the heart under low pressure. Superficial arm veins are the usual…
• vein finderA transilluminator or similar device that lights up veins under the skin to help locate a hard-to-find vein.

Study Routine Blood Collections

• Free Routine Blood Collections practice questions
• All Routine Blood Collections terms
• Venous Order of Draw, Additives and Inversions
• Phlebotomy Abbreviations and the Do-Not-Use List
• Medical Word Parts for Phlebotomy