to the break, cleaned with alcohol and covered with sterile dressing until repaired Optimally, a person familiar with the procedure will be available within a short time of clamping the catheter or folding the catheter on itself, or, if feasible, tying the broken end into a knot If the externalized portion is too small to clamp, hemostasis may be achieved by putting pressure on the site of venous entry A scar is usually apparent at this site However, if the scar is not apparent, the catheter should be palpated from the exit site on the skin to the location at which it can no longer be palpated and pressure should be applied at that site Repair kits are available for each catheter size ( Fig 135.9 ) These kits contain a new external catheter segment with a hollow male connector that fits into a cleanly sliced proximal end The kits also contain a syringe and needle to apply the glue to the male connector If an implantable catheter leaks, fluid or blood that collects subcutaneously may cause a bulge or painful swelling at the site A broken implanted catheter must undergo prompt surgical management The broken segment can often be easily visualized by chest radiography Catheter Displacement Occasionally, the patient or caregiver inadvertently pulls on the externalized portion of a tunneled catheter, and can be noted by visualization of the cuff at or outside of the exit site The venous portion of the catheter may eventually be displaced from the venous system Externalized catheters are at higher risk for dislodgment within a few weeks of insertion, because the cuff is not fully anchored by fibrosis Exsanguination after catheter dislodgment is a rare event because of the advancement of the tip inside the vein and the natural tendency toward venous hemostasis However, children with clotting disorders are at increased risk of life-threatening blood loss after catheter displacement Totally implanted devices are at risk of dislodgment at both ends; however, few events apart from major thoracic trauma place enough tension on the catheter to dislodge it from the vein Migration of the venous catheter tip is rare but can lead to cardiac arrhythmias, pneumothorax, cardiac tamponade, and superior vena cava syndrome