[header] How to draw blood from hard to hit veins [title] Make sure your tourniquet has been applied properly. [step] Applying a tourniquet increases the amount of blood in the vein to make them stand out more. The tourniquet should not be so tight that it cuts off the circulation.
[substeps] The tourniquet should be put on the arm about four inches above the vein. A blood pressure cuff that is inflated to 40-60 mm hg also works well.