The peripheral blood flow under basal conditions in normal male subjects in the third decade

Abstract

By means of a method which has been employed by us in other studies, 1–7 seventy-five measurements of the peripheral blood flow in c.c./M 2/Min. were made on thirty-four normal male subjects. In addition, the basal metabolic rates, blood pressures, and pulse rates were recorded. The results may be summarized as follows: 1. 1. The peripheral blood flow under basal conditions at 25° C. room temperature showed a range from 8 to 78 c.c./M 2/Min. in all instances except one, in which it was consistently higher. Peripheral blood flow was usually less with a lower basal metabolic rate and greater with a higher basal metabolic rate. The average for all subjects at this temperature was 52 c.c./M 2/Min. The peripheral blood flow of the subjects who were studied at 27° C. room temperature ranged from 34 to 157 c.c./M 2/Min. except for two instances, in which it was 8 and 13 c.c./M 2/Min., respectively. Again, the peripheral blood flow usually varied in the same direction as the basal metabolic rate. The average for all subjects at this temperature was 73 c.c./M 2/Min. There was overlapping of the level of peripheral blood flow at the two room temperatures, but, on the average, the flow was greater at the higher temperature. In four subjects who were studied at both room temperatures, the peripheral blood flow was greater at the higher room temperature. 2. 2. The average basal metabolic rate was the same in the two groups; that is to say, it was minus 6 per cent at 25° C., and minus 5 per cent at 27° C. Small increases in basal metabolism were recorded in 60 per cent of the experiments at the end of a morning's observations, and small decreases in 40 per cent. These changes were not of sufficient magnitude to be considered significant. 3. 3. The average rectal, skin, hand, and foot temperatures were higher at the higher room temperatures (27° C.). The increase in average surface temperature was approximately 0.4° C. for each degree rise in room temperature. At the same time, the average rise in rectal temperature was small. This constancy in rectal temperature appears to have been brought about by the allocation of more blood to the surface of the body at the higher room temperature. 4. 4. The blood pressure and pulse rate were normal in each instance, and there were essentially no differences in the averages for the subjects who were studied at 25° C. and those at 27° C.