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Central Venous Access

(At any time you can rotate the image or add or subtract structures. Clicking the link will always bring you back to a starting point. Remember to use rollovers to see the labels for the various structures. Also, by moving the axial plane to any point in the image on the right, you can see the cross-section on the lower left. Any coloration in the right image will be shown in the cross-sections.)

The goal of a central line is to gain rapid access to the right side of the heart, so that drugs can be rapidly delivered to the rest of the body.

Let's begin with the skeleton. We've omitted the clavicles and sternum and included only rib 1. From the first and second costocartilages you can infer the position of the manubrium and the Angle of Louis. (Use the index to add these in if you don't recall your landmarks.) At any time, feel free to add back skin (slider lower left) or rotate the image (wheel between the sliders). Remember to use rollovers to identify things.

Let's look at the major viens that lead to the superior vena cava. The subclavian viens and internal jugular veins are commonly used.

Part I: Subclavian vein lines (Lab 4)

We will work on the left side. To give an unobstructed view when you choose to rotate the image, we'll omit the right-side structures. Add in the clavicle. Your target is the subclavian vien, between the clavicle and first rib. Rotate the image to 305 degrees to see the flight path of your needle into the vien. Add back some skin to see where you are.

Now lets add some structures you want to avoid. First the arteries. (Remember to use rollovers to identify them) Rotate the image through 360 degrees to confirm that the axillary artery and vien are very close together throughout their course. Where do you see a gap between the subclavian vien and artery? Right! when you rotate the image to 95 degrees. Look where the vessels cross the rib.

A muscle attaches to the first rib in this gap. Add in the anterior scalene muscle . Rotate to 250 and 280 degrees to confirm how the anterior scalene separates the two vessels. Now look at 0 degrees as we remove the clavicle and then remove the subclavian vein. Mouse over the axial image to see the relationship of the clavicle, vein, muscle and artery. Therefore, you can inject the vien where it crosses the first rib and the anterior scalene muscle will protect the artery from you needle, if you should go too deep.

What else would be protected? Add in the brachial nerve plexus. These nerves supply the arm and shoulder. Your patient will let you know if you hit it!

What is near by that is at risk of injury? Add in the phrenic nerve (controls the phrenic diaphragm and one's ability to breathe). See it coursing along the anterior scalene muscle. See how the Lung extends above the first rib. It your needle goes deep you can enter the pleural cavity and cause a pneumothorax. Lastly, note a major lymphatic vessel that drains most of the body, the thoracic duct.

Let's add back the entire skeleton for one final look. Rotate this around as much as you like!

Part II: Jugular vein lines (Lab 17)

Let's begin with the bones and the sternocleiodomastoid muscle on one side. Now, we'll add the internal jugular vein and common carotid artery on both sides. Note the medial/lateral relationships of the artery and vein in the axial image. Note also the close relationship of the jugular vein and the sternocleidomastoid m.

There are several ways to locate the internal jugular vein.

You can feel the pulse of the carotid artery near the medial border of the sternocleidomastoid at the level of the hyoid bone and thyroid cartilage. The vein lies lateral to this.
You could draw a line from the mastoid process to the groove between the sternal and claviclar heads of the sternocleidomastoid muscle. The vein lies just deep to the muscle, where the heads split.
You could find the groove between the lateral border of sternocleidomastoid and the anterior scalene. (Clavicle removed for clarity.) Note that the vein is close by. What lies in the groove posterior to that (between the middle and anterior scalene muscles)? (Scapula removed for clarity). Right! the brachial plexus.