Preventive measures for catheter-associated urinary tract infections: First, if the condition permits, shorten the duration of catheterization as much as possible so as to reduce the probability of catheter-associated infections. Second, good care of the urinary catheter is required, and local disinfection with iodophor is needed daily. Before disinfection, squeeze the urethra to promote the discharge of urethral secretions, and disinfect 1-2 times a day. Third, regular bladder irrigation is required, and saline can be used for bladder irrigation to reduce the probability of catheter-associated infections. At the same time, patients need to maintain a certain amount of water during the indwelling catheter. Fourth, the catheter or drainage bag needs to be changed regularly. For patients with long-term indwelling catheters, the drainage bag needs to be changed at intervals of about 1 week and the catheter needs to be changed at intervals of about 2-4 weeks to reduce the probability of catheter-associated urinary tract infections.