Patient positioning and technique

The patients are positioned in the supine position with the left arm abducted (between 45–80°) on the swivel arm board (Figure 1a,b). The swivel arm board is a commercially available, radio-lucent accessory consisting of an arm board capable of 360° rotation mounted by a hinge joint onto a baseplate. The baseplate is positioned under the patient’s torso/left shoulder and the left arm position is fixed by taping the patient’s supinated and dorsiflexed hand to the distal end of the arm board.

(a) Picture of the swivel arm board consisting of a base plate (black), which is positioned under the patient’s torso/left shoulder and an arm board (white) connected by a rotating hinge joint. The arm board is capable of 360° rotation. (b) the arm board rotated 90° to illustrate the pivot point between the baseplate and the white arm board.

After cleaning the forearm in the sterile fashion, a sterile lithotomy drape is used to cover the mid-upper arm down to the hand, with exposure over the designated puncture site. A long sterile drape is then used to cover the patient’s body from the neck down to the feet, overlapping with the lithotomy drape over the upper left arm. This fashion of draping is important as it allows the drape on the left arm to move independently from the main drape covering the patient when the arm board is rotated.

Radial access was obtained using standard technique and medications (“radial cocktail”) as described elsewhere,^1,2 and hydrophilic 5F transradial sheaths were used (Prelude, Merit Medical Systems, Inc., South Jordan, Utah) or Radifocus (Terumo, Tokyo, Japan). Patients were eligible for transradial access if the left radial artery was >2 mm in diameter and had a Barbeau type A-C waveform.

In our practice, 45–80° abduction is the main “working” position throughout the procedure (e.g. catheter manipulation and embolic delivery) and swiveled into “hyperabduction” (>90−135°) by rotating the arm board only for CBCT acquisition (Figure 2). Typically, once the catheter/microcatheter is in position, the arm is hyperabducted for the dual phase CBCT angiography. The arm is rotated back into the working position for delivery of the embolic. After complete delivery of embolic, the arm is again swiveled into a hyperabducted position to allow completion of CBCT acquisition and then returned to the working position for hemostasis of the access site.

Mock-up pictures without the sterile drapes to show the arm positions: (a) working arm position; 45–80° abduction, (b) CBCT arm position; >90−135° “hyperabduction”. CBCT, cone-beam CT.