Due to the pulling, squeezing, and injury of anal surgery, it leads to local edema and severe pain, which stimulates the sympathetic nerve and causes spasmodic contraction of the bladder neck sphincter, thus making it easy for urinary retention to occur. Causes: ① Patients have difficulty in urination due to excessive mental tension after surgery or unaccustomed to bedside urination; ② Patients have pain in the anus and spasm of the sphincter muscle, causing spasm of the bladder and urethral sphincter muscle and resulting in inability to urinate; ③ Surgical operations are rough, local damage is too heavy and the anorectal dressing is overfilled and too tight, compressing the urethra and affecting urination; ④ Old and weak, bladder smooth muscle contraction weakness or male elderly ⑤ Insufficient anesthesia causes spasm of the urethral sphincter, which reflexively causes difficulty in urination. Treatment: ① Do the ideological work of the patient after surgery to relieve concerns, eliminate tension, choose a suitable environment for urination; 6h after surgery can not urinate on their own, with small abdominal distension and discomfort, diuretic measures should be taken in a timely manner, generally can be given bladder area heat, water flow sound to induce urination; ② pain caused by urination available analgesics, if the anorectal dressing is too tight, can be removed or reduce the dressing, in order to reduce the urethral If the anorectal dressing is too tightly packed, the dressing can be removed or reduced to reduce the pressure on the urethra; ③ Acupressure massage or acupuncture in the middle area of the four cross fingers below the umbilicus; ④ Neostigmine 0.5mg intramuscular injection can promote urination; ⑤ Furosemide injection 20mg orally can promote urination; ⑥ Indwelling catheter.