NursingCrib.com

Posted: 07 Jul 2011 10:48 PM PDT

Definition

One of the methods of collecting blood is arterial puncture. Obtaining arterial blood sample requires percutaneous puncture of the brachial, radial or femoral artery or the extraction of a sample from an arterial line. Once collected, the sample withdrawn can be used to analyze the patient's arterial blood gas (ABG) values. Determining if a patient is acidic or alkaline and assessing the oxygenation status of the patient is made possible by obtaining a blood sample through arterial puncture. The procedure is quite similar to venipuncture however, it should be done with no exposure to air to prevent the escape of gas from the arterial line and avoid intracellular fluid shift to extracellular.

Indications

Arterial punctures are usually performed for the following purposes:

Arterial blood gas sampling or assessment of the patient's acid-base balance (ph)
Ventilatory status assessment (PaCO2) or frequent need for blood sampling such as in cases of prolonged resuscitation
Oxygenation status assessment (PaO2)

Important Considerations

In extracting blood samples from the arterial line, the nurse should keep the following factors in mind for successful outcomes.

The arteries that are easier to palpate, stabilize and puncture are those that are superficial. It is also less painful for the patient if the punctured arteries are surrounded by insensitive body tissues such as muscle, tendon and fat.
Potential complications of arterial puncture are vascular spasm, clotting of the vessel or bleeding that may result to possible hematoma and vascular compression.
In cases where complication occurred, the artery should have a good collateral blood flow. It is the radial artery that meets these criteria and usually the brachial artery is the best second choice.

Equipment