Indwelling subclavian catheters and a visit with the "pinched-off sign"

Percutaneously inserted indwelling subclavian vein silastic catheters have revolutionized the administration of chemotherapeutic agents. Complications associated with insertion of such lines have always included bleeding, pneumothorax, haemothorax, arterial cannulation, and catheter displacement. Recently a patient receiving 5-fluorouracil and folinic acid for 11 months for small bowel carcinoma experienced a catheter fracture with distal segment embolization in the right atrium. A literature survey revealed 13 cases where mechanical shearing forces on the catheter caused by compression of the catheter between the clavicle and first rib were thought to be the cause for this complication. Interestingly all cases involved patients receiving chemotherapy. Radiologically, potential candidates for catheter fracture can be identified by the pinched-off sign with bending and pinching of the catheter at the thoracic inlet. Recommendations are for more lateral insertions of such percutaneously placed catheters and if the pinched-off sign is seen, then said catheters should be followed radiologically and probably should not remain in situ for longer than 6 months.