Is catheterization harmful? Catheterization is a treatment used to relieve urinary retention and can also be used during general anesthesia surgery to measure the amount of urine that the patient will urinate during the procedure and as a treatment. The main complications of catheterization are: one is damage to the urethra, and the other is internal infection of the urethra, and rarely these complications occur such as postoperative urethral stricture. If the hard cut with the help of the urethra may cause puncture of the prostate, or for rectal damage, the probability of this are almost none.