Sacral canal anesthesia is not harmful if the doctor operates in strict accordance with the operating procedures. However, there are several defects in the working process of sacral anesthesia that can cause human hazards: 1. The puncture rate of sacral anesthesia is very low, and the normal human anatomical structure changes greatly, so in many cases the sacral canal is closed and sacral anesthesia cannot be performed, so the success rate of sacral anesthesia is only about 70%. The success rate of lumbar anesthesia and epidural anesthesia is about 90% or more; 2. The blood vessels around the sacral canal are richer, and poisoning may easily occur during the anesthesia process; 3. The nerves may be damaged during the whole puncture process.