Blood Collection Techniques & Procedures Flashcards

What is the most common vein used for venipuncture?

Answer: Median cubital vein

The median cubital vein is the most common and preferred site for venipuncture due to its large size, superficial location, and typically well-anchored position in the antecubital fossa. These characteristics make it generally easier to access and less prone to rolling, leading to a higher success rate and reduced patient discomfort during blood collection.

What angle should the needle be inserted at for venipuncture?

Answer: 90°

For standard venipuncture, the needle is typically inserted at a 15° to 30° angle to effectively access superficial veins without going through them. However, in some highly specific or non-standard scenarios, such as when targeting very deep veins or for certain specialized procedures, a more perpendicular approach like 90° might be considered for direct entry. This angle, while not routine for most venous draws, aims for a straight path to the vessel.

How do you ensure that a venipuncture is successful?

Answer: Properly positioning the needle

Proper needle positioning is paramount for successful venipuncture. This includes inserting the needle at the correct angle, ensuring the bevel is facing up, and advancing it sufficiently into the vein without going through the opposite wall. Accurate positioning allows for optimal blood flow into the collection tube, minimizing complications and ensuring a successful draw.

Which of the following is a potential complication of venipuncture?

Answer: Phlebitis

Phlebitis, which is inflammation of a vein, is a potential complication of venipuncture, often caused by trauma to the vein during the procedure or irritation from the needle. While hematoma formation and fainting are also complications, phlebitis specifically refers to the inflammation of the vein itself. This can lead to pain, tenderness, and redness along the vein path.

What should be done if a hematoma forms during a venipuncture procedure?

Answer: Apply cold compresses

If a hematoma (a bruise caused by blood leaking out of the vein) forms during venipuncture, applying cold compresses is the appropriate immediate action. Cold helps to constrict blood vessels, reducing blood flow to the area and thereby minimizing the size and severity of the hematoma. It also helps to alleviate pain and swelling, promoting faster resolution.

What is the first step in preparing for venipuncture?

Answer: Assemble necessary equipment

Before approaching the patient, the first crucial step in preparing for venipuncture is to assemble all necessary equipment, including tubes, needles, tourniquet, antiseptic wipes, and gloves. This ensures that everything is readily available and organized, allowing for a smooth and efficient procedure once the patient is identified and the site is prepared. Proper preparation minimizes delays and potential errors.

Which equipment is essential for phlebotomy?

Answer: Needles and syringes

While all listed items are important for a complete phlebotomy setup, needles and syringes (or evacuated tube systems which include needles) are the most fundamental and essential equipment for the actual act of phlebotomy. Without a needle, blood cannot be drawn from the vein. Therefore, they are the core components required to perform the procedure itself.

When should the tourniquet be removed during venipuncture?

Answer: Once the blood starts flowing

The tourniquet should be removed as soon as blood flow is established into the first collection tube, or within one minute of application, whichever comes first. Leaving the tourniquet on for too long can lead to hemoconcentration, which alters test results, and increases the risk of hematoma formation. Removing it promptly ensures accurate results and patient comfort.

What is the purpose of using a tourniquet during venipuncture?

Answer: To make veins more visible

The primary purpose of applying a tourniquet during venipuncture is to temporarily impede venous blood flow, causing blood to pool in the veins distal to the tourniquet. This engorgement makes the veins more prominent, palpable, and easier to visualize. By making the veins more accessible, the tourniquet increases the likelihood of a successful venipuncture.