Figure 1

Illustration of the sequence for the guide wire exchange of central venous catheter. (a) Approximately 5 cm of the catheter external to the entry site are extensively prepared with chlorhexidine solution in 70% alcohol solution. Some parts of the catheter are more difficult to cover with the antiseptic solution. These, including the hub and connecting ports, are covered with drapes and later removed. (b) The skin surrounding the catheter insertion site is also treated with an alcohol and chlorhexidine solution, and sterile drapes are placed appropriately to cover the catheter except for the component under manipulation. The segment of catheter remaining uncovered is then covered with alcohol-chlorhexidine impregnated gauze. (c) The catheter is clamped just above its point of entry in the skin and, using sterile scissors. (d) The CVC is cut below the hub and 3 to 4 cm from the skin. (e) The external cut portion is covered with drapes. The operator then removes his/her gloves and changes to a new pair of sterile gloves. The field is further covered so that only a small skin surface of 3 to 5 cm² is exposed where the CVC enters the skin. (f) The severed cross section of the line shows the various lumens and the soft J tip of the guide wire is then inserted into the largest lumen (distal 16 gauge lumen) until it meets the resistance of the clamp. The clamp is removed with one hand, while the other holds the external part of the CVC. The wire is then advanced to 20 cm and the 'old' CVC is removed over it. (g) The operator now has a wire in place for a new central line insertion. (h) The removed CVC is placed on to the sterile drapes, the distal 5 cm portion is cut with sterile scissors, placed in a sterile container and set for subsequent microbiological culture. (i) A new catheter can now be inserted over the wire and secured to the skin as would be the case for a new CVC.