Central Venous Catheter Placement With Thoracic Ultrasound and Intracavity ECG Positioning

The goal of this interventional study is to assess the feasibility of two bedside techniques for confirming central venous catheter (CVC) placement and detecting complications: * Intracavity ECG monitoring to confirm internal jugular vein CVC tip position. * Thoracic point-of-care ultrasound (POCUS) to rule out pneumothorax following CVC insertion. Participants who require an internal jugular CVC as part of their routine care and meet all inclusion and no exclusion criteria will be randomised to receive either: * Standard care, or * The intervention, consisting of intracavity ECG guidance and thoracic POCUS. The CVC will be inserted either on the left or right side of the neck. All participants will undergo a post-procedure chest X-ray regardless of study arm, to allow comparison of the intervention methods with standard care.