Circulation Changes Following Intestinal Trauma. 89 



in the leg resulted in a 3 c.c. fall, the blood pressure was 17 mm. 

 Hg lower at the end than at the beginning. 



In the experiment of December 4, where a 2 c.c. fall in leg 

 volume was noted, the blood pressure rose from no mm. Hg at 

 the beginning to 115 mm. Hg at the end of the experiment. 



In the two experiments of November 21 and December 13, 

 the fall of volume was 5 c.c. and 10 c.c, respectively, and the 

 blood pressure was exactly maintained throughout the experi- 

 ments. The time of intestinal handling in the latter experiment 

 was two hours, with forty minutes elapsing before any change in 

 volume was noted. 



In the experiment of March 18, there was a fall in leg volume 

 of 9 c.c. and a gain in blood pressure of 20 mm. Hg. 



In the experiment of January 9, which lasted one hour and 

 thirty-two minutes, the leg volume at the expiration of thirty-one 

 minutes had decreased 5 c.c. and the blood pressure had risen from 

 107 mm. to 118 mm. Hg. There was a gradual loss of vaso-motor 

 tone in the leg vessels from then on, the leg increasing in volume, 

 the blood pressure showing a steady fall. Within a few minutes 

 of death there was a rapid fall of leg volume, the decrease at 

 death being 10 c.c. 



Conclusions. 



Trauma to the exposed intestines brings about a certain vaso- 

 motor response in the blood vessels of the periphery, and this 

 response is a vaso-constriction. This change begins almost im- 

 mediately that the intestines are disturbed and continues as long 

 as the stimulation is applied. 



This reflex vaso-constriction in the peripheral vessels is an 

 important factor in maintaining the blood pressure in cases of 

 gradually developing shock from intestinal trauma, overcoming 

 the blood pressure lowering effect of the splanchnic dilatation. It is 

 shown that whenever the intestinal irritation is not accompanied by 

 vaso-constriction of the peripheral vessels, the blood pressure tends 

 to fall. Whenever the vaso-constriction is present but slightly, 

 the blood pressure shows itself to be better maintained. When the 

 vaso-motor centers can bring about a marked vaso-constriction, 

 the tendency towards the maintenance of the general blood pres- 



