Indications: 1. Acute urinary retention, unsuccessful catheterization or no catheterization. 2. Special surgery requiring puncture to establish a cystostomy. Contraindications: 1, the bladder is not filled. 2, those with a history of lower abdominal surgery, peritoneal reflexion and pubic bone adhesions fixed. Preparation: Preparation of instruments: cystocentesis kit (F14 open-sided cystocentesis needle puncture and F14 female latex balloon catheter instead of cystostomy tube), 2 pairs of gloves, treatment tray (0.5% iodophor or 2% iodine, 75% ethanol and adhesive tape, local anesthetic, sterile paraffin oil, 10 ml syringe, vial of saline), drainage bag. Operation method: l. Supine position, without shaving. The lower abdomen is disinfected with 0.5% iodophor or 2% iodine, 75% ethanol, the operator wears gloves, spreads a towel and checks the instruments. 2.Before puncture, touch the distended bladder above the pubic symphysis. If the bladder is not distended, sterile saline must be instilled into the bladder from the urethra until it is distended. 3, Local anesthesia with 1% lidocaine is applied to the bladder wall at the midline of 2 transverse fingers above the pubic symphysis. 4, Use a fine needle or a common lumbar puncture needle at the point of local anesthesia and the abdominal wall at an angle of 45?downward and backward to pierce the bladder. There was a feeling of emptiness into the bladder and urine was withdrawn. The fine needle is withdrawn and the depth of skin to bladder is measured. 5, then make a skin incision at the puncture site about 0.5cm long, use F14 open-sided cystocentesis needle (F14 balloon catheter is put in the sheath in advance) and the abdominal wall into the bladder at a 45?angle downward and backward, after there is urine overflow, then insert the catheter downward 3~4cm. remove the puncture needle, the balloon position in the bladder, inject 10ml of water to prevent the catheter from slipping out, and connect the end of the catheter to the drainage bag. The incision does not need to be sutured, covered with a dressing and fixed with adhesive tape. This cystostomy has the following advantages: ① avoid surgery and achieve the same effect as surgical fistula; ② easy method, less pain, the patient can walk on the floor after surgery, no hospitalization; ③ if the tube is placed for a short period of time, the fistula will be closed after extraction, no leakage; if the tube is placed for a long period of time, the tube can be changed once every 2-4 weeks, easy method; ④ during the period with the tube, the tube can be clamped periodically to train the bladder; ⑤ avoid the discomfort of urethral tube placement ⑤ avoid the discomfort of urethral placement, and men can also avoid acute testicular epididymitis caused by urethral placement. It should be noted that when the bladder is not full, such as puncture can accidentally enter the abdominal cavity or puncture the intestinal canal, so it must be punctured when the bladder is full, and the puncture point should not be too high. Q & A: 1. How should the bladder puncture needle and catheter be handled without urinary overflow? First of all, we should consider whether the puncture needle has entered the bladder, and then enter a certain depth or adjust the position of the puncture needle appropriately if necessary; if there is still no urine, we should consider that the needle hole is blocked by a blood clot and can be flushed with sterile saline; for bladder contusion or hemorrhagic cystitis, if the bladder is full of blood clots, the puncture should be abandoned and suprapubic cystostomy should be performed instead. 2.What are the precautions for suprapubic cystocentesis? ① Strictly grasp the indications and contraindications; ② Make sure the bladder is extremely full before puncture. ③ Strictly aseptic operation to prevent the occurrence of infection. ④The puncture point must not be too high to avoid accidental puncture into the abdominal cavity. ⑤The direction of the puncture needle must be oblique downward and posterior, and should not be too deep to avoid accidental injury to the intestinal canal. ⑥When suctioning urine, the puncture needle should be fixed to prevent swinging and maintain the depth to reduce bladder injury and ensure suction effect. (7) After bladder puncture, if no drainage tube is left in place, further treatment of lower urinary tract obstruction should be arranged promptly to prevent extravasation of urine at the eye of the needle when the bladder is full. (8) Try to avoid repeated simple cystocentesis to draw urine. Excessive punctures can lead to bladder bleeding and intravesical infection. ⑨ After cystocentesis, urinary tract anti-inflammatory medication should be used appropriately.