P007: IF YOU HIT THAT VEIN, BE READY FOR SOME SERIOUS SPURTIN'!! ABERRANT, VENOUS-APPEARING RADIAL ARTERY IN A CARDIAC SURGICAL PATIENT.
Keya A Locke, Geetha Kannan, Zachary Deutch, Adrriene Warrick; University of Florida-Jacksonville
Background: Arterial cannulation for monitoring beat-to-beat blood pressure is essential in cardiac surgery, as well as other high risk cases. Various techniques are used to cannulate the radial artery, which is generally easy to access. Normal anatomical location of the radial artery (and its pulsation) is on ventral aspect of the wrist.
Case description: A 56 year old male with history of hypertension and coronary artery disease was scheduled to undergo CABG, and presented in the preoperative holding area. A perioperative nurse approached the patient to start an intravenous line and was told, “Do not stick me there, that is not a vein, it is my radial artery.” When patient was interviewed by the anesthesia team, he reported that during a prior operative intervention, he was told that large, classically venous-appearing vessel on the dorsomedial aspect of his left hand was discovered to be his radial artery, not a vein (figure 1). This vessel was palpated and a strong pulse was appreciated, while ultrasound images were also taken of it, which confirmed pulsatile flow (figure 2). A large-bore intravenous catheter was placed elsewhere on the extremity, and a 20-gauge radial arterial line was placed in this vessel without problem and was used for duration of the case with no complications. The arterial line was discontinued on post-op day 3, with no reported complications.
Discussion: The radial artery arises from the bifurcation of the brachial artery in the antecubital fossa, and courses distally on the anterior part of the forearm, where it serves as a landmark for the division of anterior and posterior compartments. The artery winds laterally around the wrist, passing through the anatomical snuff box and between the heads of the first dorsal interosseous muscle. It then passes between the heads of the adductor pollicis and becomes the deep palmar arch, which joins the deep branch of the ulnar artery (9).
Numerous sources in the anatomy and plastic surgery literature have reported varieties of aberrant radial artery. There is a wide range of reported incidences, from 1:56,000 to 1:3,440 (8, 13). A study by McCormack et al in 1953 involved the dissection of 750 cadavers, and is likely the largest examination of anatomical specimens to date (15.) This study reported that the incidence of aberrant radial artery to be 0.8%.
There have been instances in which the artery is accidentally cannulated, and injection of various medications given. This can lead to ischemia of the hand and tissue necrosis, especially when there is poor ulnar collateralization. However, in this case, we were fortunately able to avoid this pitfall, based on the patient’s enlightened self-advocacy (i.e. telling us what not to do!). When such foreknowledge is not available, and intra-arterial injection occurs, treatment recommendations include: leave the catheter in place, consider performing sympathetic block of affected extremity, heparinization via the catheter, Phentolamine 5mg with Papaverine 30-65 mg (may be repeated every 3 hours), elevation of affected extremity, and careful monitoring for regional perfusion defects.