Blood test

Depending upon what your doctor is looking for, any of the following may be tested:

  • blood flow through the vessels
  • blood clotting factors and components
  • blood cholesterol levels
  • blood sugar (glucose) level
  • blood calcium levels
What is involved
No special preparation is needed. Blood is drawn from a vein in one arm. Your arm is first cleaned with an antiseptic and then a tourniquet (an elastic band) or a blood pressure cuff is placed around the upper arm, which causes the veins in the lower arm to fill with blood. A needle is inserted into the vein and the blood is collected in a vial or syringe. Once blood is taken, the needle is removed and a bandage is applied. The whole procedure should take no more than five minutes.