In 1936 Leslie and one of us1 reported the quantitative and qualitative platelet values in the blood of 40 normal newborn infants. Since this time we have shortened and simplified the method used until we now believe that it may be easily and simply employed in any laboratory. As one of the principal changes from our original method is the shortening of the plasma centrifugation, which will conversely reduce the coagulation time of the plasma fractions, the following study was made.
The method of qualitative and quantitative platelet analysis was used as formerly described.2 Blood was withdrawn directly from a vein in chilled oiled syringes, and any sample containing cerebrospinal or tissue fluid was discarded.It must be emphasized that if any difficulty is encountered in obtaining the blood so that there is addition of tissue fluid or cerebrospinal fluid, the results will be unreliable. This can