Patients may need to fast prior to certain blood tests. For example, patients should not eat or drink anything except water for 10-12 hours prior to glucose and lipid profile tests.
The amount of blood drawn at the time of collection for laboratory testing depends on the tests that are ordered. Usually the amount collected is very small (around 10-15 ml.)
Some patients become anxious when they have their blood drawn. Patients should tell the health care professional who is drawing the blood if they feel faint or sick. Slow deep breaths prior to the needle stick may help to alleviate anxiety
After a blood draw, the phlebotomist makes sure that all signs of bleeding have stopped. A Band-Aid is applied to the arm for a minimum of 15 minutes.
Aspirin or other anticoagulant (blood thinners) drugs can prolong bleeding. In such cases, patients may need continued applied pressure until the bleeding has stopped. A cold pack may be necessary to reduce swelling and bruising.
After a patient has blood drawn, even when bleeding has stopped, patients should not carry heavy objects with that arm for a minimum of one hour.