Studies on acidosis and dyspnea in renal and cardiac disease / Francis W. Peabody, Boston.

  • Peabody, Francis Weld, 1881-1927
Date:
1914
Catalogue details

Licence: In copyright

Credit: Studies on acidosis and dyspnea in renal and cardiac disease / Francis W. Peabody, Boston. Source: Wellcome Collection.

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    stream of a mixture of carbon dioxid and air. The mixture was analyzed for every experiment, so it was known at what tension of carbon dioxid the blood was saturated. After thorough saturation by running in this mixture for thirty minutes, and after thorough shaking, the blood was transferred by means of a glass syringe, and with con¬ stant care to prevent loss of carbon dioxid, into the electrode vessel. This vessel had previously been filled with the same mixture of car¬ bon dioxid and air, so that there was no opportunity for the blood to lose carbon dioxid while it was being passed into the electrode vessel. The vessel and the side tube were completely filled with blood so that no bubbles of air remained. Then the side tube was connected with the hydrogen apparatus and blood allowed to run out of the lower end of the vessel until the neck of the vessel was filled with hydrogen, and the platinized electrode was just dipping into the blood. After shaking for ten minutes to promote a more rapid diffusion of gases, the electrode was allowed to stand. Readings were then made from time to time until a constant end-point was reached. Sometimes this occurred quickly, but usually it took two or three hours. All obser¬ vations were made in duplicate, and at room temperature. The results were calculated and the temperature corrected to 18 C. (64.4 F.), using the formulas which are given in Sorensen’s article.11 The results are expressed in the now familiar terms of Sorensen as the ph.16 It is to be remembered that the more alkaline a solution, the higher the ph., and the more acid, the lower the ph. When saturated at 40 mm. carbon dioxid the ph. of normal blood is approximately 7.45. Taking the high and low limits the extreme variations are between 7.40 and 7.50. In all instances the ph. of the blood was determined when it had been saturated with a mixture containing carbon dioxid at about 41 mm. tension. This carbon dioxid tension may be considered as that at which the blood is saturated in the body when the alveolar carbon dioxid is normal. In normal individuals, therefore, it gives the actual ph. of the blood. If, however, the carbon dioxid in the alveolar air is below normal, as in cases of acidosis, the saturation at 41 mm. carbon dioxid will give a more acid value for the blood than is actu¬ ally present. This is at least true in the majority of instances, for we 16. “Aus Zweckmassigkeitsgriinden, die besonders bei graphischen Darstel- lungen der Abhangigkeit zwischen dem Verlauf biologischer Prozesse und der Wasserstoffionenkonzentration des Mediums hervortreten hat S. P. L. Sorensen vorgeschlagen als Mass fiir die Grosse der Wasserstoffionenkonzentration einfach der numerischen Wert des Exponenten der oben erwahnten Potenz von 10 zu benutzen und die Bezeichnung PH. anzuwenden. . . .” “Unter dem Wasserstoffionenexponenten, PH., einer Losung ist der Brigg’sche Logarith- mus des reziproken Wertes des auf Wasserstoffionen bezogenen Normalitats- faktors, der Losung zu verstehen.” Sorensen: Ergebn. d. Physiol., 1912, xii, 401.