Nikolay's father also worked as an estate manager for the major general Vladimir Voeykov (ru) who served in the Svita of Nicholas II and was close to the Emperor's family.

Once again, he became involved with the student protest movement and had to spend a year in the Kherson Governorate treating children with typhus, tuberculosis and other epidemic diseases.

During that time he worked a lot as a surgeon and took part in medical expeditions around the country to fight epidemics of typhus, smallpox and scarlet fever.

He served in the field ambulance detachment in Manchuria and was shot in the arm while saving wounded under hostile fire during the Battle of Te-li-Ssu.

[3] With the start of the World War I in 1914, Burdenko once again volunteered for the frontline and joined the Red Cross detachment of the Northwestern Front, taking part in the East Prussian Operation and the Battle of the Vistula River.

In March 1917, he was appointed the Main Battlefield Medical Inspector, but left the post on May due to disagreements with the Russian Provisional Government and returned to front.

Following the occupation of Yuryev by German forces Burdenko was suggested to continue to carry out his duties under the new power, but he declined the offer and in June 1918 evacuated to Voronezh along with other professors.

His researches concerned shock prevention, healing of wounds and infections, surgical treatment of tuberculosis, anesthesia, blood transfusion and so on.

[4][8] Burdenko was among the first to introduce surgery of the central and peripheral nervous system to clinical practice; he investigated the reasons behind the appearance of shock and the methods of treating it, made a large contribution to the study of the processes which appear in the central and peripheral nervous system in connection with the surgical operation in the case of sharp injuries; he developed the bulbotomy — operation on the upper division of the spinal cord.

He also headed the All-Union Association of Surgeons and became a member of the USSR Academy of Sciences in 1938, the same year he joined the Communist Party of the Soviet Union.

With the start of the Great Patriotic War in 1941, he was appointed the Main Surgeon of the Red Army and participated in some of the first battles that took place near Yartsevo and Vyazma.

[4][7] During one of the Nazi bombings, Burdenko survived another heavy concussion which led to a stroke; he also completely lost ability to talk and had to train hard to regain it.

[7] He investigated various Nazi crimes, including attacks on medical personnel, hospital trains and Red Cross units.

He also headed the special commission of forensic medical examination that revealed atrocities committed during the Nazi occupation of the Smolensk and Oryol Oblast where over 215 000 Soviet civilians were murdered.

[9] The commission's report assigned Nazi Germany the responsibility for the massacre,[9] factually carried out by the NKVD (People's Commissariat for Internal Affairs), the Soviet secret police.

Based on the autopsy performed by 75 doctors, evidences found on corpses and testimony collected from witnesses, the commission reported that the massacre happened during the autumn of 1941 and that methods used to kill Polish officers were identical to those used by German forces during occupation of Soviet cities.