78 INFLUENCES AFFECTING THE LEUCOCYTES 



sonic substance that produces a leucocytosis allowance in inter- 

 preting the results must be made for the effect of the substance 

 administered. 



Post hemorrhagic leucocytosis. A distinct leucocytosis occurs 

 following hemorrhage (after traumatism or other causes). Huncr- 

 lauth found in six dogs with a loss of blood amounting to about 

 4% of the body weight that there was first a slight decrease 

 in the number of leucocytes after operation followed by a 

 marked increase on the following day (maximum 43,700) which 

 persisted two or three weeks. Lyon in experimental hemorrhage 

 in dogs found that there was an initial decrease within a few min- 

 utes after operation, followed soon by a marked increase which 

 reached a maximum in six to eight hours, decreased rapidly after 

 three to four days but persisted in moderate degree for days or 

 weeks. The majority of the leucocytes during leucocytosis Rieder 

 found to be polynuclear, as high as 97%. Rieder repeated the 

 experiments on three dogs, finding a leucocytosis except in one 

 case where there was no increase. In Rieder's cases the amount 

 of blood lost had been replaced by injections of an equal volume 

 of sterile salt solution. In general the transfusion of salt solution 

 seems to increase the amount of the leucocytosis. The grade of 

 leucocytosis varies with the amount of blood lost, there being a 

 greater increase with a greater loss of blood. It varies with the 

 powers of regeneration of the individual and is greater with severe 

 than mild hemorrhage and with rapid than slow loss of blood. 



