What is intravenous blood sampling or venipuncture?

Intravenous blood collection or venipuncture is a professional act.

Intravenous blood collection should be performed by a blood collection employee who is competent and capable. A physician, if convinced of competence, may grant his extended arm so that the employee may, under his responsibility, perform this operation independently.

What can you do yourself?

• For routine examinations, it is recommended to be sober. In practice, a period of at least 4 hours after a light meal is sufficient for a check-up.
  of at least 4 hours after a light meal. The use of snacks and beverages, other than water, is not allowed shortly before the blood draw.
• The blood sample should not be taken immediately after strenuous physical activity.
• Stress should also be avoided before and during blood sampling.
• Make sure you are not cold A good blood circulation makes it easier to take blood samples and there is less need to push.

Some medications can affect the outcome of determinations: for example, cortisone and pretnisone increase alkaline phosphatase and affect cortisol determination.

For the blood draw, you sit down. A tourniquet will be put on your arm so you can see the veins running. In order to take one or more tubes of blood, the blood collection assistant will prick a vein on the inside of your elbow. As the blood starts to flow, the tourniquet will loosen. The veins become more visible when you make a fist. You should not continue to squeeze with the fist. The tourniquet is loosened as soon as the blood enters the blood collection tubes.
flow. Too long a stowage can lead to hemolysis. Several tubes can be filled by one puncture.

Immediately after disconnection, the tubes will be gently mixed by turning them over and over 5 times. The professional blood collection worker will prevent excessive congestion, foaming and haemolysis, as this can cause the blood values of some tests to be too high.
Tubes containing an anticoagulant (EDTA paase tube or NaFl gray tube) should be filled as far as possible because the amount of anticoagulant is adjusted accordingly. Tubes with an anticoagulant medium will be filled several times immediately after the blood draw
be shaken carefully to avoid clots. For blood imaging studies, blood is collected in a (purple) EDTA tube and sent without centrifugation. The EDTA blood should preferably be stored at room temperature until the time of shipment.
For clinical chemistry tests, a red tube with a gel at the bottom is usually used to send it qualitatively.
For the exact determination of glucose, Blood Value Test uses gray sodium fluoride tubes for blood collection.

Click here for an overview of the types of tubes used

In most cases, blood sampling does not take longer than five minutes. The Infection Prevention Working Group does not consider skin disinfection necessary for punctures of patients with normal resistance, although scientific evidence for this is weak.



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