To the Edltor:
We detected an intravascular injection by ultrasound during performance of a supraclavicular brachial plexus block. A desirable view of the subclavian artery, first rib, and brachial plexus1 was obtained at a depth of approximately 4.0 cm (Fig 1A). When the needle tip was thought to be near the plexus (by visual evidence on the ultrasound screen and elicitation of a distal muscular twitch response), an initial injection was begun after a negative aspiration. A grayish blush was immediately noted on the ultrasound screen within the subclavian artery upon injection of the first mL of local anesthetic. The injection was stopped and blood was seen entering the tubing connected to ...