HEMORRHAGIC SHOCK— OVERTON and Dk BAKEY 



385 



90 



80 



70 



60 



ti 50 



40 



30 



20 



86% 



50 



11 

 46 



_8_ 

 20 



64% 



29 



45 



' No survivors 

 No. cnlmals 



ontrol Cooling Chlorpromozine ChiorpromazineChlorpromazineChlorpromozine 



5mg. 5mg 50mg. 50mg. 



+ Cooling + Cooling 



Fig. 3. — Experimental hemorrhagic shock, number of animals tolerating hypotension eight hours. 



is the decreased rate of the blood loss in the dogs receiving the drug in large doses 

 (table I). This decrease in amount and rapidity of bleeding in these animals may 

 be a reflection of the initial hypotension. The average blood pressure at the be- 

 ginning of the experiment was 93 mm. Hg in the control dogs ; 94 mm. Hg in 

 the hypothermic dogs ; 84 mm. in the 5 mg. chlorpromazine-treated ; 90 mm. in the 

 5 mg. of chlorpromazine and cooled group and 73 and 80 mm. Hg, respectively, in 

 the group receiving the larger dosage of drug alone or in combination. The better 

 survival rates in the 50 mg. chlorpromazine and cooled dogs as compared with those 

 receiving the drug in large dosage alone is not entirely explained on this basis, for 

 despite the lower initial blood pressure, both groups were bled almost identical 

 amounts and in essentially the same period of time. This would suggest an actual 

 augmentation of effect when surface cooling was combined with the drug. Other 

 workers have pointed out the apparent better tolerance of the organism to hypo- 

 tension produced by sympathectomy, anesthesia or autonoinic blocking agents than 

 to hypotension mediated entirely by acute hypovolemia, and perhaps the beneficial 

 effects reflect a lesser volume of the hemorrhage.^* This does not mean that the 

 drug in large dosage had no beneficial effect on the shock experiment, but the results 

 must be interpreted cautiously. Hypothermia and the smaller dosage of drug, 

 however, augment compensation in another fashion, since the volume and rapidity 

 of loss of blood in these animals closely approximated those of the controls. 



