What was Pirogov’s contribution to the development of domestic and world medicine during the Crimean War?

In November 1854, at the very beginning of the Crimean War, Pirogov went to the front with a team of doctors and nurses. Performing operations on the wounded, he was the first in Russia to use a plaster cast, which reduced the number of amputations. Earlier, while serving in the Caucasus, he was the first in Russian surgery to apply anesthesia (etheric) during an operation. He continued this during the Crimean War. In addition, Pirogov is considered the founder of military field surgery, since during the Crimean War he introduced new orders: he sorted the wounded according to the severity of their injuries. Some relied on an on-site operation, while others were taken to hospitals in the rear.