AEROTHERAPEUTICS. This literal ly means the treatment of disease by air and is usually limited to the supposed value of air in certain chest diseases, notably of tuber culosis, and the use of compressed air for special chest conditions.
This is a difficult subject to treat since there is so much popular tradition and medi cal superstition regarding the of air in the treatment of chest conditions. The gen eral attitude that regards open-air treatment of tuberculosis as of prime importance stands in marked contrast to the position taken by the few that the air per se has little or noth ing to do with the matter. In fact the open air treatment of tuberculosis is a vastly much more organized program than its name would imply. Under the general idea of "open-air" is included exercise, freedom from work, ex tra feeding, psychotherapy, humidity, skin stimulation, etc., etc. The air itself in real ity plays an insignificant part in the therapy. The reason for this is plain. It is well known that the sole stimulus in air is the oxygen contained within it. It is also an axiom of physics that the composition of the air so far as its gases are concerned is constant the world over at the sea-level and under average conditions. There is no more oxygen in one air than another and no less unless in a her metically sealed space specially treated by physi cal procedures. Hence oxygen transfer in the lung is constant under the same barometric pres sures and temperatures. Rarified air in high places contains differing proportions of oxy gen but here the problem is not so much one of the oxygen as of the barometric pressure and the relationships of the tension of oxy gen in the tissues and the external atmos phere and carbon dioxide tensions in the tis sues. Special problems arise here which are in need of special forms of consideration, which cannot be discussed here. Here oxy
want develops a special type of illness — mountain sickness." Water and air (oxygen) are among the most constant things in the environment. They rarely ever change in their gross com position, hence they have built up invariable interactions between the body and the environ ment. The real work of supplying the proper amount of oxygen takes place within the lung tissues and is not dependent upon the exter nal oxygen supply which is always ample and constant under the ordinary conditions of life.
Hence it can be seen that although the physiology of respiration is extremely com plex, there is, properly speaking, no real prob lem of air treatment in the ordinary sense, and the "open-air" treatment of tuberculosis is a misnomer. The largest factor is an elab orate psychotherapy. The oxygen itself plays the least role in the therapy. Popular miscon ceptions regarding air in buildings, in theatres, in subways, etc., etc., are abundant. When the laity speaks of "bad air," it really means foul-smelling humidity, heat and other things. The air, so tar as its oxygen and the respira tory needs are concerned, is not "bad." It is constant all over the world—in the garret or in the cellar, rooms with windows open or windows shut—the oxygen never varies. The aesthetic wishes of individuals vary and make them prefer sleeping porches or inside rooms and thus the psyche is affected. The actual respiratory needs are equal everywhere under similar atmospheric pressures and simi lar temperatures. Consult Bayliss, 'General Physiology' ; Henderson, 'Fitness of the En vironment.'