Owen, Robert L.

We describe an unpredictable clinical scenario involving an intraoperative vascular injury during an elective total shoulder arthroplasty. Shortly into the procedure, the patient became acutely hypotensive due to frank hemorrhage. The patient experienced a complete transection of the third segment of the axillary artery caused by an unrecognized bone fragment, suspected to have dislodged into the joint space following a traumatic ground-level fall 12 months prior. Emergency vascular surgical intervention was required for hemostasis.

The interscalene brachial plexus block is a well-described and widely used peripheral nerve block effective for regional anesthesia and analgesia in orthopedic surgical procedures of the shoulder, upper arm, and clavicle. Conventionally, an in-plane ultrasound-guided approach has been the technique of choice, while the out-of-plane approach, though less described, has been gaining anecdotal momentum among a growing number of proceduralists. This pro-con discussion highlights the out-of-plane approach’s goal of avoiding needle injuries to nerves that course through the middle scalene muscle and the in-plane approach’s benefit of whole-shaft needle visualization and increased distance away from the plexus on entry. We aim to provide a comprehensive comparison to guide proceduralists in their clinical decision-making.