Solves the mystery of decompression sickness: Who is Paul Bert, the Father of Aviation Medicine?

(1833-1886) French physiologist and politician. He has worked on respiratory physiology and tissue transplantation in animals. He was born on 18 October 1833 in Auxerre. He went to Paris in 1853 to study law, then medicine and natural sciences. He started working under Claude Bernard at the College de France, earning his degree in law in 1857 and natural sciences in 1860, and his postgraduate degree in 1863 with a thesis on tissue transplantation in animals. After completing his doctorate in natural sciences in 1866 with his thesis titled De Li vualıte propre des tissus animaux (“On the Essence Vitality of Animal Tissues”), he became a professor of zoology and physiology at the University of Bordeaux in the same year, and in 1868 comparative physiology at the Museum Histoire Naturelle. brought to the chair. Bert, who took over the chair of physiology vacated by Bernard at the Sorbonne the following year, took a break from his scientific studies and entered politics in 1870 when the Franco-Prussian War began. He became governor of the Northern provinces in January 1871, was elected a deputy in 1872, and served as education minister for a short time between 1881 and 1882. Bert, who was appointed as the governor-general of Annam and Tonkin in 1886 to suppress the uprisings against the French colonial regime in Indochina, died of dysentery on 11 November 1886 in Hanoi, a few months after he took office.

Paul Bert (17 October 1833 – 11 November 1886) was a French zoologist, physiologist and politician. He is sometimes given the sobriquet "Father of Aviation Medicine".

After the defeat of the French army in Sedan against Prussia and the dethronement of Napoleon III in September 1870, Bert joined the national resistance movement led by Leon Gambetta, the interior minister and close friend of the newly formed Government of National Defense. He continued his political activity, which started at that time, until his death. After the end of the Prussian War, he became the most ardent representative of the wing that advocated the retake of Alsace and Lorraine, the rich mining regions that France left to Prussia, in the Assembly, where he joined as a deputy from the Liberal Republican Party in 1872. During the revolts against the French rule in Indochina in 1885, he was one of the leading supporters of his country's expansion policy in that region and argued that his colonies should definitely not be disposed of. The following year, when he was sent to Indochina as the first civilian governor, he maintained peace in the region by preventing military forces from interfering in the administration, although his administration was short-lived. He spearheaded the founding of the Tonkin Academy.

In contrast, he is best known for his education policy when he was minister of education in the Gambetta Cabinet between November 1881 and January 1882. Bert, who sees education as the basis of political, economic, and cultural development, supported liberal lawmaker Jules Ferry's bills on education reform and advocated free and compulsory primary education, especially the establishment of a secular education system based on science. Hauling the necessity of secondary education for girls and giving biology and zoology lessons to female students at the Sorbonne for years, Bert also assumed the editorship of the journal Revues between 1879 and 1885, as he advocated reflecting all scientific developments to the public.

Bert's work in the field of physiology was greatly influenced by his teacher Bernard, especially the experimental physiology methods he developed and the concept of the "internal environment". In the 1860s, the subject of Bernard's first studies, which he continued as a student and assistant, was tissue grafting and organ transplantation methods in animals and the properties of preserving the vitality of tissues. Bert, who examined the adaptability of the tissues and organs that he grafted or transplanted to the new "environment" with his experiments on mice, came to the conclusion that tissues and cells could survive in a suitable environment while maintaining their viability.

Beginning in the 1870s, he focused his research more on comparative physiology, especially respiratory physiology. He studied the respiratory organs of vertebrates and invertebrates, and the differences between the respiratory mechanisms of aquatic and airborne creatures; As a result of his experiments on skin respiration, he came to the conclusion that the amount of oxygen in the blood changes according to the outside air pressure. In those years, in France, which started a major reconstruction movement, deaths of unknown origin began to be seen among workers working in the construction of underwater tunnels or bridge foundations. Bert, who started to investigate how external environment changes such as atmospheric pressure affect the organism and what changes low and high pressures cause in the indoor environment, when Bernard was a student, attributed this "highlight" to the relationship between the amount of dissolved gas in the blood and air pressure. According to their research, an increase in the partial pressure of oxygen in the blood at higher than normal air pressure or a decrease at low pressure causes death in both cases. Like the workers working in the deep, when the pressure was changed from high pressure to low pressure, the organism could not adapt to this situation, and the nitrogen, which was more easily dissolved in the tissues at high pressure, was released when the pressure suddenly decreased and made bubbles in the blood and tissues.

In his work ("Barometric Pressure"), published in 1878, Bert proposed a gradual transition from high pressure to normal pressure in order to avoid this "high pressure" phenomenon. In the same work, he gave the results of his experiments on both animals and himself, examining the physiological effects of low and high pressure in terms of adapting to the environment, and he claimed that those living in high areas had more than normal red blood cells in their blood. This assertion was later confirmed by studies of Peruvian inhabitants. It was Bert who suggested the use of an oxygen cylinder against oxygen deficiency caused by low pressure. Inspired by the relationship between the air pressure and the gas pressure in the blood, he thought that the pressure should be kept a little high in order for nitrogen monoxide to be used as an anesthetic, but considering that pure nitrogen monoxide creates oxygen deficiency (asphyxia), he decided to use a ratio of 1/6 oxygen to 5/6 nitrogen monoxide. He had success by testing a mixture on a dog at 1/5 atmospheres of pressure. With all this work, Bert is considered a pioneer of respiratory physiology and aviation medicine.