Feasibility Study of “Snuffbox” Radial Access for Visceral Interventions
This report represents a feasibility study of the use of “snuffbox” radial access in the visceral interventions. “Snuffbox” radial access refers to access of the dorsal radial branch located on the dorsum of the hand between the first and second digits. Its use has been recently reported in cardiology literature for patients with limited mobility, operator positioning convenience, and for use as an alternative access due to radial artery limitations.
The authors retrospectively report 50 snuffbox accesses in 31 patients, the majority of which were for hepatic oncologic interventions. The access was performed under ultrasound guidance with a micropuncture set. A size cutoff of 16 mm was utilized for slender 5-F sheaths (48 accesses) and 20 mm for slender 6-F sheaths (2 accesses). 3,000 IU heparin were given after access as well as 200 µg of nitroglycerin at the beginning and end of the case.
Technical success rate was 100%, defined as ability to use the intended access for the visceral intervention, and there was one access site complication that required no intervention (2-mm pseudoaneurysm, self-resolving). The average vessel size was 2.1 mm, and there was a mean of 1.6 accesses per patient.
Overall, the authors found this access point to be successful. Intra-procedurally, it allowed for subjectively more ergonomic patient positioning, but the added length to the access did necessitate most cases be done with 110-cm length catheters. Hemostasis required more diligence due to the mobility of this anatomic region.
Access needle inserted under US guidance with a guide wire inserted. (Inset) US of the access site in the distal radial artery in the anatomic snuffbox over the trapezium.
This report represents an early evaluation of the use of the dorsal radial artery branch (“snuffbox”) for use in visceral interventions. Radial access has increased in popularity and frequency with visceral interventions, piggy-backing on the large coronary literature. Its safety and efficacy are well documented, especially in anticoagulated patients and those necessitating early ambulation.
The use of the snuffbox for access is relatively new in both the coronary and visceral angiography literature. The authors demonstrate its high technical success rate in this report. The advantages of this access are at this point theoretical. The dominant finding thus far has been a subjective increase in patient and operator preference for positioning, as the hand is not supinated for this access. Additional theoretical advantages are preservation of the palmar radial artery branch to the hand and sparing of direct access of the radial artery proper (and associated risks).
At this point, snuffbox access has been demonstrated to be technically feasible and can be viewed as an alternative or bail-out option in the appropriate patient. Further research in larger cohorts will be necessary to allow for evaluation of the safety and efficacy for visceral interventions, especially given the proven safety and efficacy of traditional radial and femoral artery access.
Click here for abstract
Pua U, Sim JZT, Quek LHH et al. Feasibility Study of “Snuffbox” Radial Access for Visceral Interventions. J Vasc Interv Radiol. 2018; 29(9): 1276-1280.
Daniel P. Sheeran, MD
Department of Radiology and Medical Imaging
Division of Vascular and Interventional Radiology
University of Virginia