The two ends of the nerve that feels pain are in the skin and the brain respectively. To feel pain, it is necessary to ensure that the nerve endings of the skin can transmit pain signals to the brain. If the brain doesn't receive feedback from the skin, even if you see a knife wound on your body, you won't feel pain.

Anesthesia is to block the transmission of signals in the nerve through drugs. Anesthetic drugs are generally harmful to nerves, and general anesthesia will affect brain nerves. In short, it is best not to do general anesthesia.