Instructed patient Wipe the connecting ends of the drainage bag with alcohol or iodine before you reconnect the bag to the tube. This helps prevent infection. Instructed patient check the catheter to be sure it is in place after you change your clothes or do other activities. Do not wear tight clothing over the tube. Place the tubing over your thigh rather than under it when you are sitting down. Be sure that nothing is pulling on the nephrostomy tube when you move around.