SubclavianNEJManatIn patients requiring central venous access, which vein do you prefer? In descending order, I prefer subclavians, internal jugulars (IJ), and then femorals.

There is increasing evidence that subclavian central venous lines are superior to femoral lines (JAMA 2001) with respect to iatrogenic infection and thrombosis rates. In 9% of subclavian lines, however, the line tip ends up in the ipsilateral IJ, instead of the superior vena cava (SVC) – see chest xray below. These lines are unusable in the long term because of the risk of cathether thrombosis in this low-flow area. The line must must be rewired.

What’s a common technique to minimize this complication risk?

Insert the guidewire into the needle such that the J-tip of the wire points inferiorly. This will allow the wire to float into the SVC moreso than the IJ.


Trick of the Trade:

Ambesh Maneuver

I use this trick regularly. It is a technique which I read about in the Anesthesia literature (Anesth 2002) published by Dr. Ambesh. The Ambesh Maneuver involves the simple external compression of the IJ vein during guidewire insertion.


Ambesh maneuver: Staged demo on a volunteer.

Don’t worry, the needle was photoshopped to make it look like I punctured the skin. Also in retrospect, I would have draped more sterilely.

Put your a sterile finger at the base of the IJ in the supraclavicular fossa during guidewire insertion. The guidewire will meet resistance if it attempts to cannulate the IJ. This maneuver reduced the incidence of ipsilateral IJ cannulation from 6% (control) to 0% (Ambesh maneuver).


Michelle Lin, MD
ALiEM Founder and CEO
Professor and Digital Innovation Lab Director
Department of Emergency Medicine
University of California, San Francisco
Michelle Lin, MD


Professor of Emerg Med at UCSF-Zuckerberg SF General. ALiEM Founder @aliemteam #PostitPearls at Bio:
Michelle Lin, MD