Clean catheterization, also known as intermittent catheterization, is a method of catheterization without an indwelling catheter that can be performed by non-medical personnel (the patient, a relative or a companion) to reduce the patient’s dependence on medical personnel and to increase the patient’s independence. It has been commonly used internationally for patients with spinal cord injury and other neurological paralysis. Indications】 Patients with spinal cord injury or other neuropathies who cannot urinate on their own or have inadequate voluntary urination (residual urine more than 80~100 ml), are clear and cooperate actively. Contraindications】 1.Severe injury or infection of the urethra, and pressure sores in the urethra. 2.The patient is confused or uncooperative. 3.Receiving large amounts of infusion. 4, systemic infection or extremely low immunity. 5.There is a significant bleeding tendency. 6.Significant prostate hypertrophy or tumor. Instruments and equipment] No special equipment is needed. You can use the thinnest catheter of sufficient length. Operation procedure】 1. Clean the catheter with 0.9% sodium chloride solution or other medical disinfectant without mucosal irritation (Neosporin, etc.) and set aside. 2.Clean the patient’s perineum locally with soap or cleaning solution. Wash the operator’s hands (can be the patient or the escort). 3.Insert the catheter into the urethra and push it in slowly until the urine is discharged from the catheter. In male patients, note that the urethral opening is directed towards the abdomen to avoid injury to the urethral isthmus. Before insertion, lubricant (e.g. paraffin oil) can be applied to the outside of the catheter to reduce insertion resistance. 4.Remove the catheter immediately after the catheterization is completed. 5.Wash the catheter with water after removal, and then put it into medical disinfectant solution without mucosal irritation or 0.9% sodium chloride solution for storage. Boiling disinfection can also be used. 6.Frequency of use If the patient is completely unable to urinate on his own, the frequency of use can be 3~4 times/day; if he can partially urinate, the frequency of use can be 1~2 times/day. The urine coming out of each catheterization is usually about 400 ml (physiological bladder capacity). Clean catheterization can be stopped when the residual urine is less than 80~100 ml. Precautions] 1. Patients must have a system of regular and quantitative drinking and urination so that the timing of catheterization can be reasonably selected. 2.Patients generally do not need to consume more than 2000 ml of water daily and keep the urine volume around 800~1000 ml/d. 3.Although the catheter does not emphasize strict sterilization, it is still important to emphasize adequate cleaning and reasonable preservation. 4, The insertion action must be gentle and non-violent to avoid urethral injury.