Document Xz6rEk7KjkvDeqjVZRQ8JNza4

588 HEINZ SPECHT TABLE 2 Solubility of Atmospheric Gases in Water and Olive Oil at 28 C." Solubility (ml./ml.) Oil-water Gas Water Olive oil ratio Oxygen Nitrogen Helium Argon 0.023 0.0127 0.0087 0.026 0.112 0.0667 0.0148 0.1395 4.9 :1 5.24:1 1.7 :1 5.32:1 equilibrium a large amount of gas may be stored in the fatty tissues. The,r^l fat in aeroembolism is similar to that in decompression sickness. More will said of it in the following sections. As far as other substances in the body? concerned, the capacity of the body for simple solution of gases is almost j due to the water or fat content, and no further distinction need be made her! this property. The solution of gases in the body, including oxygen and carbon dioxidj not readily analyzed by experiment until recently, although much work^ use of gases for estimating cardiac output and lung function is in the lite^aiS The converse, or desaturation, has been studied intensively in devel(fpm|| means of obviating caisson disease and aeroembolism. Data on nitrogen fijHB tion16'18 are shown graphically in Figure 2 and indicate the involvemeiiff system of at least two components; fat and water, for which an empirical mation was developed. It has been shown further by Smith and Morales1 700- |i420- / Woter,Nitrogen _____ i?l------ f 5) l-""?" s280- Fol Nitrogen 140 40 SO 120 160 200 240 280 320 360 ......... ... ....... TIME.-MIN.-------------- vVkjjr Figure 2. Elimination curve for nitrogen." Total nitrogen (A) represents the"fff^jAgc the values for nitrogen elimination from three men (average weight 64 kg.) who breathe^ oxygen at atmospheric pressure. Water nitrogen (B) and fat nitrogen (C) are hypb^hetT curves showing the absorption or elimination of nitrogen by the body so1vents.'The Valujl^fc? -nitrogen-on-fAi-are-npproximate'ly-the-sum-of-correspbnding-values-'oiH'S-lF-and-Ie )--~z "L. A. Shaw, A. R. Behnke, A. C. Messer, R. M. Thomson, and E. P. Motley, Physiol, 112, 545 (1935). "R. E. Smith and M. F. Morales, Bull. Math. Biophys., 6, 125 (1944). "R. E. Smith and M. F. Morales, Bull. Math. Biophys., 6, 133 (1944). EFFECTS OF ABNORMAL ATMOSPHERIC PRESSURE 589 sfflSwii pfmements in the consideration of physical constants of the various media ^fnw'tflS'tklcumulation of gases, the avenues of saturation and desaturation, and ^ffPioiSWtjable them to set up a general theoretical expression for the gain or mm* from the whole or any portion of the body. They consider the. effects #^Jliolume' kld flow, tissue volume, surface presented, permeability, i gas concentration. This analysis is shown in Figure 3 to fit well mm Theory Experiment 40 BO too 120 140 160 t SJS iTfital nitrogen gas uptake by limb tissues." <t>, a function of total nitrogen absorbed time t, is the counts of radioactive krypton at one minute intervals. rimental data, and it is apparent that a rational and basically sound ,'iuft,ioa|i,bfinjleveloped. WhTemperature of the Atmosphere, Its Origin and Variation pplllfre are dealing generally with body temperature under conditions of ^functional integrity, it would not seem that the environmental tem- jays any major role in the response to atmospheric pressure change. [gijSfi%tTyariation in body temperature lies probably between 28 and 40 C. ^^^^^^P^'the solubility of gases generally falls with increased temperature, BpprcpjM^^iagnitude of the change is relatively small. The temperature co- chemical reactions in vivo is found to be of a moderate order ^anaS^ciyehilby the Arrhenius relation, which states that the rate of reaction is 8wS.<glCT8^febled for every 10 C. rise.21 .. .................... ttfier hand, certain physiological responses to temperature changes of are exceedingly marked and important to the economy of l^gjipjthorjbody, though by indirection. A consideration of atmospheric tem- be included here to be drawn upon later in explanation of ^^j^n^esponses-fe-alteraribnsrihT3ressure-a1rffltitade'^2------------------------------------ %Su10i1 . Blum, Photodynamic Action and Diseases Caused by Light. Reinhold, New York1 IArmstrong, Military Surgeon, 79, 133 (1936). H. G. Armstrong, Principles and' viation Medicine. Williams & Wilkins, Baltimore, 1938.