A client has consented to have a central venous catheter placed. The best position in which to place the client is the Trendelenburg position. The reason is that the Trendelenburg position:

1. A

   Allows the physician to visualize the subclavian vein

2. B

   Reduces the possibility of air embolism

3. C

   Reduces the possibility of hematoma formation

4. D

   Makes the procedure more comfortable for the client

Appeared in: NORCET 6 mains-2024

Explanation

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• The Trendelenburg position (head down, feet up) increases the pressure in the large central veins, such as the subclavian and jugular veins.
• This increased central venous pressure creates a positive pressure gradient relative to atmospheric pressure.
• This positive pressure prevents air from being sucked into the open vein during cannulation, thereby reducing the risk of a potentially fatal air embolism.
• A secondary benefit is that this position causes the veins to distend (engorge with blood), making them a larger and easier target for the physician to cannulate.

Why Other Options Were Wrong

• Option A: The subclavian vein is a deep anatomical structure and cannot be visualized through the skin. Its location is identified using anatomical landmarks or, more commonly, ultrasound guidance.
• Option C: Hematoma formation is primarily related to the insertion technique (e.g., multiple attempts, arterial puncture) and the patient's clotting ability (coagulopathy), not their position.
• Option D: The Trendelenburg position is generally uncomfortable. It can cause a feeling of pressure in the head and may make breathing more difficult for some patients, especially those with respiratory conditions or obesity.

Related Visual

Clinical Relevance

• Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Positioning for Central Venous Catheter (CVC) Insertion as background academic context rather than a clinical decision trigger.
• The nurse's role is crucial in correctly positioning the patient for CVC insertion and monitoring for any adverse effects of the position, such as respiratory distress.
• Recognizing the signs of an air embolism (sudden dyspnea, chest pain, hypotension, tachycardia, 'mill wheel' murmur) is a critical nursing responsibility, requiring immediate intervention.
• What if the patient has a head injury or severe respiratory disease? In such cases, the Trendelenburg position is contraindicated. The procedure would be performed with the patient flat or in a slight reverse Trendelenburg, while taking extra precautions like timing insertion with the patient's exhalation to prevent air embolism.

How to Approach the Question

• First, identify the core of the question: it asks for the primary reason for using the Trendelenburg position during CVC placement.
• Think about the major risks and goals associated with inserting a catheter into a large central vein. The two main considerations are: 1) making the vein easy to access and 2) preventing life-threatening complications.
• Evaluate each option based on these two points.
• Option A (visualization) is incorrect because the vein is deep. Option C (hematoma) is about technique, not position. Option D (comfort) is factually wrong; the position is uncomfortable.
• Option B (air embolism) addresses a major, potentially fatal complication that is directly influenced by the pressure dynamics changed by the Trendelenburg position. This makes it the most critical reason and the correct answer.

Concept Tested & Keywords

• Concept Tested: Positioning for Central Venous Catheter (CVC) Insertion
• Stem keywords: central venous catheter, Trendelenburg position
• Lead-in keywords: best position, reason

Question ID

QGIvDGh8oIvdQ29k0eEw9f

Copy ID

Reference Book

E6 Nursing Brunner Adult Health 3SA Vol 1 Part 2 p. 105-107