THE VELOCITY OF BLOOD FLOW IN INFANTS AND YOUNG CHILDREN, DETERMINED BY RADIOACTIVE SODIUM 1

Abstract

The velocity of blood flow in infants and young children was measured objectively by using radio-active Na. Na, activated by cyclotron bombardment, was made into a neutral, sterile soln. of NaCl. At a conc. of 2%-5% NaCl, the test dose of 2-5 microcuries/kg of body wt. was contained in less than 1.0 cc. The circulation rate was detd. by recording the time elapsed between the inj. of the test dose into one arm and its arrival in the opposite hand. The latter was signalled by a Geiger counter from which a circuit was arranged to record the sudden increase in count on a waxed tape running at constant speed. By this method, the rate in 22 children between 2 and 12 yrs. averaged 11 sec. with a range of 5-17 sec. The rates of 14 infants between 6 wks. and 22 mos. of age averaged 7 sec. with a range of 3-12 sec.