Does general anesthesia require a catheter?

Does general anesthesia operation need to insert urethral catheter? We determine according to the type of operation and the operation time. If the operation time is short, no more than one hour, we can not do catheterization treatment, because catheterization will cause certain pain to the patient, but if the operation time is long, more than two hours, then we need to calculate the fluid replacement of the patient during the operation, and catheterization is needed. General anesthesia relaxes the muscles of the whole body, the bladder detrusor muscle is also relaxed, and urine is stored in the bladder. After the patient wakes up after surgery, if the urine accumulated during the operation is full of bladder, it will cause pain in bladder due to detrusor relaxation, which will bring pain to the patient. In addition, the catheter also plays a monitoring role under general anesthesia. It is inevitable to observe urine volume during the operation, which can prompt the patient whether there are shock signs.