I remember a time before the ultrasound when all the central lines I would do (except for coagulopathic patients) were subclavian lines. I had a real concern about the rate of pneumothoraces using the internal jugular approach. Now, they are all I will do. Thanks to the ultrasound. You don’t have to be an ultrasound expert to do this, just know how to hold a vascular probe over the neck and press a little. The vein compresses the artery doesn’t.
Why is it so important to use? The Internal Jugular Vein lies antero-laterally to the common carotid artery in most cases. However in about 25% of cases, it lies anterior to the common carotid, thus making it more likely to puncture the artery, when using the traditional technique (Cardiovasc Intervent Radiol. 2005;28:303–306). With ultrasound the needle can be visualised at all times, ie., we can see the needle passing through tissue and into the vessel, minimising the risk of arterial puncture.
In the second image, the large vein has been compressed, however the artery due to its muscular walls is not compressible. This allows us to differentiate vein from artery.