Gen. Guan Yu from the Records of the Three States was shot by a poisoned arrow and seriously got injured during a battle. A skilled physician named Hua Tuo saved Guan Yu’s life by pulling out the arrow and scraping the poison from the bone. Guan Yu calmly played go during the surgery. This is a fictional story but similar accounts can be found in the stories of great commanders across the ages and in all countries around the world.
Alexander the Great ran into a castle on his own in the last battle of his Indian campaign. During the fight, he was hit by an arrow on his right flank. The tip of the arrow might have touched his artery. When a physician named Cristobulus drew the arrow out, fountain of blood gushed from the wound. His artery could have been ruptured by slight movement but he refused to have others hold his body tight and did not budge an inch during the surgery.
It is not clear whether these stories are real or made up just to make commanders look more charismatic and create a legend. Even if they were true, those emperors and commanders had a rare opportunity of receiving a surgery. Medical treatment in field warfare was almost useless even until in modern warfare. More soldiers died of disease than in action due to ignorance to germs and terrible hygiene. British military in the 18th century lost 10 percent of its troops every month because of diseases.
Treatment of the injured was even more terrible. Soldiers who were shot had to have their body part amputated. There were piles of amputated arms and legs in war hospitals from 18th to late 19th centuries. It is not a treatment from a modern medical perspective. But it was justified during those times: medical treatment at that time was ignorant and incapable. Our society nowadays is using similar measures: When there is a problem, we simply cut it off. This is far from a treatment and also uncivilized and even criminal.