Supposed Presence of Carbon Monoxide in Normal Blood, etc. 515 



definite information on this point, and we hope to make the subject of a 

 communication in the near future. 



The expenses in connection with this work were defrayed by means of a 

 ! grant made by the Government Grant Committee of the Boyal Society, for 

 which we take the opportunity of expressing our thanks. 



On the Supposed Presence of Carbon Monoxide in Normal Blood 

 and in the Blood of Animals ancesthetised with Chloroform. 

 By G. A. Buckmaster and J. A. Gardner. 



(Communicated by A. D. Waller, M.D., F.E.S. Beceived August 12, 1909.) 

 (From the Physiological Laboratory of the University of London.) 



While engaged in the study of the gases of the blood during the various 

 stages of anaesthesia by chloroform, we found after absorption of the carbon 

 dioxide and oxygen extracted by the blood pump an amount of residual gas 

 far in excess of any amount that could be regarded as nitrogen remainder plus 

 leak of apparatus.* We have found as the result of many experiments, 

 carried out to determine this particular point, that practically all the chloro- 

 form present in the blood of anaesthetised animals comes off with the gases 

 •of the blood when these are extracted at 40° C, so that the excessive residual 

 gas is in large part chloroform vapour, or its decomposition products. The 

 exact method of procedure of analysis of these gases and the effects of the 

 presence of this chloroform on the methods of analysis will form the subject 

 of a forthcoming paper, but we quote the following experiments to show what 

 percentages of chloroform may be present : 



Cat, weight 3 kilos. ; chloroformed for one hour with an air-chloroform 

 mixture 2 — 3 per cent., 54 c.c. of dark blood withdrawn from carotid artery. 



The gases extracted with the pump at 40° C. were mixed with excess of 

 pure moist oxygen and passed through red-hot spiral platinum tubes. The 

 products of combustion were collected in ammonia. This was exactly 

 neutralised with nitric acid and titrated with silver nitrate (1 c.c. = O'OOl CI) ; 

 17 c.c. of silver nitrate were required = - 01986 gramme CHC13 = 3"7 c.c. of 

 chloroform vapour at 0° and 760 mm. 



* The blood pump employed was the Tcepler as modified by Barcroft ('.Journal of 

 Physiology,' vol. 25, p. 265), with certain modifications for this particular work. These 

 'will be described in our paper on the blood gases in chloroform anaesthesia. 



