Epidural spread of injectate from a costoclavicular catheter due to selective lodging in the middle trunk

While catastrophic complications related to interscalene catheters are well-documented, we illustrate the potential for epidural spread associated with a costoclavicular catheter.

A fluoroscopic image was obtained following the injection of 3 ml of iohexol through a 20G epidural catheter placed in the costoclavicular space under ultrasound guidance using an out-of-plane approach. This was done to determine the pattern of drug spread and guide the volume of local anaesthetic to be infused for postoperative pain relief. Rather than a diffuse spread in the costoclavicular space, a tubular pattern of contrast spread was noted with spillage into the epidural space at the level of C6 and C7, indicating a spread confined to the middle trunk (Fig. 1A; Supporting Information, Video S1).

We hypothesise that the catheter entered the sub-epineural space at either the lateral or posterior cord and travelled along the relevant division of the middle trunk (Fig. 1B). With this spread, continuous infusion of local anaesthetic could have resulted in bilateral phrenic nerve palsy, hypotension and bradycardia. Identification of epidural spread led us to remove the catheter promptly, averting potentially life-threatening complications [1, 2]. Fluoroscopy is an established technique in performing perineural injections [3]. We propose that it may be a similarly useful method to understand the course of perineural catheters.