Abstract
Central venous catheter (CVC) placement using the Seldinger technique represents a routine procedure in intensive care units; however, it is still burdened by a non-negligible risk of mechanical complications, often underestimated in clinical practice. Guidewire malposition is a rare event, but it may lead to unpredictable consequences when the course occurs in extravascular locations adjacent to osteomuscular structures. We report the case of a patient with severe cerebral hemorrhage in whom, during CVC insertion, the formation of a guidewire loop in the subclavian region occurred. The loop was completely extravascular and became entrapped in the clavicle-first rib space, making removal impossible during the procedure. This event provides an opportunity to discuss the anatomical mechanisms of malposition, the importance of early recognition, and the multidisciplinary management required to prevent iatrogenic injury.