The Naval Order of the United States will commemorate the 100th year of (U S) naval aviation, and naval aviation medicine, at its 2010 Congress in October. This event got me to thinking about the history of aviation medicine, and led to what will be a series of short jottings on the topic.
Long before the invention of aircraft, men–landlubbers all: naval aviation will have to wait a few centuries to emerge–observed the human effects of altitude. J. A. de Acosta, a Jesuit, described as “mountain sickness” the hypoxia symptoms he experienced during his 16th century sojourn in the Andes mountains. Descriptions exist of mountain sickness symptoms suffered by Chinese traders during their journeys through the Hindukush and Karokorum mountains of Pakistan and Afghanistan 1600 years earlier still.
Robert Boyle (of Boyle’s Law of gases), through self-experimentation in a barrel-vacuum chamber of his own design, was able to establish some notions about altitude physiology in 1677. But it wasn’t until the 19th century that French physiologist Paul Bert, again by means of self-experimentation, laid down the foundation of modern altitude physiology and elucidated the cause of altitude and decompression sickness. Berg actually used his own altitude chamber to systematically chart the physiological effects of altitude up to 8800 meters.
The field of aviation dates its beginning from the first flight of de Rozier and Laurent, who ascended in a Montgolfier brothers balloon on 1 November 1783. They reached an altitude of 900 meters. An American physician, John Jeffries of Boston, is given credit for being the first true “flight surgeon” based on his undertaking a “full investigation of the nature and properties of the atmosphere which surrounds us” in his first ascent, 1784. This was only the beginning.
Jacques A C Charles reached >8200 m in a hydrogen balloon of his design, in 1783. From this flight we also have Charles’s description of ear pain caused by pressure change. Etienne-Gaspar Robert and M. Lhoest attained 7000 meters in 1803 and described tachycardia and general lethargy at altitude. A year later, Andreoli, Brasette and Zambeccary suffered frostbite, nausea and dizziness in their ascent to 7000 m, while in 1862 Glaisher and Coxwell rose to 8800 m, and despite fainting, lived to tell of the palpitations, difficulty breathing, cyanosis and difficulty reading their instruments as they ascended. Spinelli and Sivel, however, died from effects of hypoxia in an ascent to 8000 m in 1875; they carried oxygen with them, but not enough to support them during their flight. In 1901, German meteorologists Berson and Süring survived reaching the height of 10500 m. by breathing supplemental oxygen. These men reported that the oxygen relieved their difficulties in breathing, and their feelings of fear disappeared; yet Süring lost consciousness, and only by luck was Berson able to initiate their descent from danger.
These experimenters chronicled the serious symptoms of breathlessness, lethargy, cognitive difficulty and other effects of hypoxia. Clearly, the advancing science of physiology needed to be applied to the study of the effects of altitude, and means of preventing altitude sickness found if safe flight was to become a possibility. Austrian physiologist von Schrötter was an important early contributor to our scientific knowledge, and in 1894 started a series of balloon studies at high altitude using oxygen equipment of his design; he also developed the first oxygen mask for aviation use. Other scientific efforts–like the 1911 Pikes Peak (4300 m) Expedition led by Oxford scientists C Gordon Douglas and J S Haldane and Yale trained researchers Yandell Henderson and Edward Schneider–with systematic examination and documentation of the physiology of altitude adaptation, would add to this essential knowledge.
To be continued. My references for this little exploration are the chapter on the history of aviation medicine by Viktor Harsch in Principles and Practice of Aviation Medicine, Claus Curdt-Christiansen, Jörg Draeger and Jürgen Kriebel, Eds., and Aviation Medicine from the Aeronauts to the Eve of the Astronauts, an exhibit at the National Library of Medicine, 7 Feb – 18 May 1979.