Mapping the danger zones: new ultrasound study aims to make vein access safer

This study uses ultrasound to measure the distance between the subclavian vein and nearby risky structures like the lung and artery. Researchers will compare two ultrasound probe positions (above vs below the collarbone) and check if arm position changes the safety margins. About 55 adults scheduled for surgery will have a quick, non-invasive scan after falling asleep. The goal is to provide clear anatomical data to help doctors avoid complications when placing central lines.