Perioperative Clinical Considerations in a Patient With Carotid Agenesis: A Case Report.

An 86-year-old female with previously diagnosed congenitally absent right internal carotid artery presented for total shoulder arthroplasty. Bedside ultrasonography confirmed the anomaly and identified several arterial collateral vessels. No aberrant vessels were seen traversing the brachial plexus. The patient received brachial plexus blockade and general anesthesia for the procedure. Carotid agenesis is associated with increased prevalence of intracranial aneurysm. Patients are often asymptomatic due to adequate blood supply from collateral vessels. Ultrasonography for brachial plexus blockade or central line access may yield initial diagnosis or confirm a preexisting anomaly that has anesthetic implications. These prospects encourage vigilance in perioperative imaging.