[Cave: interscalene catheters].

Interscalene regional anesthesia is an established and highly effective procedure; however, it represents an increased level of risk due to the close proximity of anatomical structures, such as the cervical spinal cord and many vessels. Furthermore, due to inadvertent placement of a catheter close to the cervical spinal cord or into a vessel, as opposed to a single shot injection technique, it remains a latent danger until it is removed. This article describes seven  cases of misplaced catheters. The etiology and symptoms are discussed as well as recommendations regarding the prevention of catastrophic complications. As a result, internal practice guidelines are recommended for anesthesia departments in order to enhance the safety and quality of regional anesthesia.