text: injury causes 800ml of bloodloss-how would heartrate, arteriole diameter, capillary beds maintain blood pressu injury causes 800ml of bloodloss-how would 1.heartrate, 2.arteriole diameter, 3.capillary beds respond to maintain blood pressure? please help! i guess the body would try the following: a) try and get more water to increase blood volume to the possible extent b) collapse (decrease diameter of) the blood vessels to a small extent to decrease the overall volume available for the blood