67. BLOOD CO2 ABSORPTION AS FUNCTION OF CO2 PRESSURE: MAN 



Data are for normal blood at temperatures corrected to 37°C. [l] Values for oxygenated blood are means of values 

 in the literature, the 100% range being approximately ± 5 ml gas per 100 ml blood; other data are calculations based 

 upon these means. [2-11] Major factors which influence CO^ absorption include state of oxygenation, temperature, 

 hemoglobin concentration, and alkali reserve. [1,6-9,11-13] 



III Calculated by equation: [ H2CO3] = 100QpCO2/760. where [H^COsJ = vol % of free CO^, and alpha is the solu- 

 bility coefficient for CO2 with the values at 37°C of 0.490 for whole blood, 0.440 for cells, and 0.531 for plasma. 

 [ 13-15] HI Includes both HCO3- and NHCOO^ as the rounded difference between total and free CO2. /3/ Reduced 

 blood values calculated from: [ C02]0 + [ C02]b = [ CO2IR, where [ C02]0 = total CO2 of oxygenated blood at a 

 given CO2 pressure, [ C02]b = average increase in bound CO2 with complete reduction, and ( C02]R = total CO2 

 of reduced blood. [2-12] /4/ For cells in contact with plasma at equilibration. Calculations based upon assumed 

 mean cell volume of 45 ml/100 ml arterial blood (corrected for pH and oxygenation), and derived by equation: 

 [C02]c = ([C02]b-[C02lp x [l-h]) 1/h, where CO2 is in ml/ 100 ml of cells (c), blood (b), or plasma (p), and h is the 

 cell volume as a decimal fraction of blood volume for any given pH and oxygenation. [ 13, 16-18] /5/ For plasma in 

 contact with cells at equilibration. Calculations are based upon CO2 of whole blood using "f" values of Van Slyke, 

 Sendroy, and Liu, and an estimated O2 capacity, pH, and state of oxygenation. O2 capacity estimated from CO2 

 absorption curve of oxygenated whole blood using Cartesian nomogram of Henderson, Bock, Dill and Edwards. 



Plasma CO2 = [ C02]b x "f". [ 18, 19] /6/ Calculated from equation: pH = pKj + logt '''°^J^7q|^cO^ P?22. where 



[ CO2JP is total vol % of plasma CO2, and 0.0699 (the factor, op/7.6) expresses dissolved CO2 in vol % of plasma. 

 pK|, taken as equal to 6.11 at 37°C, is the Hastings, Sendroy, and Van Slyke average for human serum at 38°C plus 

 a temperature correction of 0.005 at 37°C. [13, 15, 20] 

 Contributor : Root, R. W. 



References : [ l] Eisenmann, A. J., J. Biol. Chem. 99:359, 1932. [2] Means. J. H. 

 33:201, 1921. [3] Liljestrand, G., and Linhard, J., J. Physiol., 



L. , ibid 54:32, 1920-21. [ 5] 

 Dill, D. B., Vancaulaert, C. 



1927. [7] Parsons, T. R., J. Physiol., Lond. 51^:440, 1917. 

 S., ibid 48:244, 1914. [9] Joffe, J., and Poulton, E. P., 

 Hall, F. G., and Robinson, S., J. Biol. Chem. 136:449,1940. 



[T2] Bock, 

 D. D., "Quant- 



Bock, A. v., 

 Lond. 53:420, 

 Peters. J. P., 



Hurxthal. L. 



and Woodwell, 

 1919-20. 



Barr, D. P.. 

 M., Stoddard. 



M. N.. J. Exp. M 



[4] Davies, H. W., Haldane. J. S., and Kennaway, E. 



and Rule, F. D.. J. Biol. Chem. 45:489, 1920-21. [6] 



J. L., Bock, A. v., and Henderson. L. J., ibid 7 3:251 



[8] Christiansen, J.. Douglas, C. G., and Haldane. J 



ibid 54:129. 1920-21. [10] Dill. D. B., Wilson, J. W. 



[ 11] Henderson, L. J., "Blood: A Study in General Physiology," New Haven: Yale Univ. Press, 1928 



A. v.. Field, H.. and Adair, G. S., J. Biol. Chem. 59:353, 1924. [ 13] Peters. J. P.. and Van Slyke 



itative Clinical Chemistry," vol II, Baltimore: Williams and Wilkins. 1931. [ 14] Van Slyke, D. D., Sendroy, J., Jr. 



Hastings, A. B.. and Weill. J. M.. J. Biol. Chem. 78:765, 1928. [15] Dill, D. B.. Edwards. H. T., and Consolazio. 



W. v., ibid 1_1J:635, 1937. [16] Dill. D. B.. ibid 76:543. 1928. [17] Albritton, E. C, "Standard Values in Blood," 



Philadelphia: W. B. Saunders Co., 1952 (value from Table 94). ( 18] Henderson, L. J., Bock, A. V.. Dill, D. B., 



and Edwards. H. T., J. Biol. Chem. 87:181. 1930. [ 19) Van Slyke. D. D.. Sendroy. J.. Jr., and Liu, S. H.. ibid 



9^:547, 1932. [20] Hastings. A. B., Sendroy. J., Jr., and Van Slyke. D. D.. ibid 79:183, 1928. 



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