566 ADVENTURES IN RADIOISOTOPE RESEARCH 



about 15 minutes. During this time, the oxygen taken up by the patient 

 is replaced in the gaseous mixture. Subsequently, a blood sample is 

 secured. 



The determination of CO in the blood sample was carried out by making 

 use of Wennesland's palladium chloride method (1940). Under the 

 action of sulphuric acid, CO is given off by the blood sample placed in 

 a flask. The CO released diffuses into another flask connected with the 

 first one and containing a known amount of palladium chloride. Special 

 precautions are taken to avoid a loss of CO while connecting the flasks. 

 Some palladium chloride is reduced to palladium under the action of CO. 

 When determining the amount of palladium chloride still present at the 

 end of the experiment, we can calculate the amount of CO given off by 

 the blood sample. The determination of the remaining amount of palla- 

 dium chloride was carried out after rotating the blood-sulphuric acid 

 mixture for 3 — 4 hours. 



The blood volume was calculated according to the formula 



-^, , , cm^ CO administered • 100 



Blood volume =: 



volume per cent CO in the blood sample 



RESULTS 



The results from determinations of the corpuscle content by the ^-P 

 method performed on the same subject at different dates is seen in 

 Table 4, while in Table 5 is given a survey of all our determinations 

 carried out with application of the ^^P method. The mean value of the 

 corpuscle content per kgm body weight is found to be 36.0 gm. 



The corpuscle content obtained when applying the CO method is 

 obvious from Table 6 which contains also data found when using the 

 dye method. While the CO method is a direct method of determination 

 of the corpuscle content, the dye method is an indirect one, the corpuscle 

 content being calculated from the plasma volume and the hematocrit 

 value. 



As seen in Table 6, the corpuscle content determined when applying 

 the CO method is larger than the corpuscle content found when making 

 use of the ^'^P method. This discrepancy is possibly due to the uptake 

 of CO by other compounds than by the haemoglobin present in the 

 corpuscles of the circulating blood (comp. Asmussen 1942). 



That the corpuscle content calculated from the plasma (dye) volume 

 and the hematocrit value is larger than the corpuscle content determined 

 when applying the^-P method, can be interpreted in two different ways. 



(a) The plasma volume technique gives a falsely high plasma volume, 



(b) the plasma ratio of the circulating blood is lower than the plasma 



