Site Selection
SUBCLAVIAN LINES |
|
---|---|
ADVANTAGES |
DISADVANTAGES |
Direct path to right atrium favorable for cardiac access |
Trendelenburg positioning (often not tolerated in respiratory distress) |
Hemodynamic monitoring with CVP, CvO2, and PA catheter placement |
Risk of pneumothorax (L>R) |
Improved patient comfort and can be ambulatory |
Risk of hemothorax with subclavian artery puncture |
Reproducible anatomy regardless of patient BMI |
Not compressible, higher risk of bleeding with coagulopathy |
When to consider a different site:
- If lung disease, performing on site ipsilateral to lung pathology.
- Generally avoid in a patient with coagulopathy.
- Prior condition that alters local anatomy: clavicular fracture, indwelling pacemaker or defibrillator.
Catheter length: 15cm
Anatomy:
Technique
Positioning:
- Supine & Trendelenburg (10°) with towel roll between scapulae: reduces risk of air embolus and minimally engorges of subclavian vein. Accentuates anatomical landmarks.
- External rotation of ipsilateral arm & gentle traction: increases the size of the deltopectoral groove.
- Experienced operators may perform this procedure in upright positions if patient unable to tolerate Trendelenburg.
Locating access point: (infraclavicular access)
NOTE: this procedure is often done at UCSF using anatomic guidance instead of ultrasound guidance.
- Identify the middle third of the clavicle & follow it laterally until it deviates from the ribs. Subclavian vein and artery are medial and inferior to this point.
- Be aware of any pacemakers or defibrillators, in general do not place a subclavian on a side with a device.
Preparation:
NOTE: the finder needle may not be long enough to reach the vein. Infuse local anesthetic along the clavicular periosteum as this is richly innervated.
Entry: (infraclavicular access)
- Ensure entry site is 2cm lateral and 2cm caudal to the middle third of the clavicle.
- Direct needle tip infraclavicular aiming toward the sternal notch at a 30° angle to the skin.
- Keep the needle parallel to the floor (deltopectoral groove) and aim for the clavicle. Once you have hit bone, march down until just below the clavicle.
- Once under the clavicle, advance needle approximately 4-5cm while continuously aspirating.
- If unsuccessful, withdraw needle and redirect more cephalad.
Pearls:
- Externally rotate the ipsilateral arm with gentle traction to increase depth of the deltopectoral groove.
- Once the vein is found, rotate the needle 90˚ so that the bevel is facing caudally. This ensures ease of wire advancement to SVC.
- Rotate head contralateral to compress ipsilateral IJ & improve wire advancement to SVC.
- Access to the vein occurs just beneath the clavicle, but it may be several centimeters below skin.