There are many gospels in medicine that are taught but have not received close scientific scrutiny. Just look at the latest ACLS protocol for resuscitation. Quickly, before they change it again in a year and you have to pay more money to renew your certification and memorize new algorithms.
In the latest issue of Anesthesiology, a study has come out that puts to rest one dogma that has been taught to anesthesiologists since the start of invasive monitoring was invented: never cannulate the brachial artery. We usually try to monitor the patient through the radial artery because it is superficial and relatively easy to access. However, sometimes the patient has had too many ABG's drawn from that site or patient has poorly palpable radial pulses. Then it is always tempting to go to the brachial artery.
But, no, no, no, we were told never to insert a catheter into the brachial artery. The main offense is that there is little collateral circulation to the upper extremity if the catheter reduces the blood flow to the arm or the artery becomes thrombosed. Then you're dealing with an ischemic dead arm that may require surgery to correct.
In the article from the Cleveland Clinic, the researchers evaluated over 21,000 patients from 2007 to 2015 who had brachial artery catheters. The looked for complication over the subsequent six months. The authors found that there were only 41, or 0.19%, patients who had complications that could be attributed directly to the catheter. Of those, only 33 were considered vascular complications. Eight had infection at the site of the catheter. They did not record any neurologic injury from brachial artery catheters.
Overall, the authors state that brachial artery catheterization does not have any more rates of complications than radial artery monitoring. One more "truth" that has been debunked.