The Red Cell Volume in a Hospital Population

INTRODUCTION The normal values for red cell volume have been widely accepted as 26 to 33 ml/kg in males and 22 to 29 ml/ ^9 in females (Dacie and Lewis 1966) and Mollison (1967) quotes figures of about 30 ml/kg in males and 23.4 to 27 ml/kg in females, referring to five papers reporting investigations with radioactive iron (55Fe and 59Fe) or radioactive phosphorous (32P). Using radioactive chromium (51Cr), Retzlaff, Tauxe, Kiely and Stroebel (1969) found values which give approximately the following: in 40 "normal" males 26.8 ml/kg; in 38 normal" females 23.2 ml/kg; and in 12 "obese" females 17.3 ml/kg. The mean weight of the latter was 86.2 kg (189.6 lb.). The present study was undertaken to determine the red cell volume in the normal subject using 51Cr. In view of the difficulties in obtaining large numbers of healthy volunteers, some patients who were willing to volunteer for the test were investigated. These were all Patients who were about to be discharged from hospital and had been up and about in the wards for at 'east seven days, and who had no clinical evidence of ar,y heart failure, bleeding or abnormality of fluid balance or active infection.