| Popis: |
Although the blood pressure is one of the important criteria in the standardization of hemorrhagic shock in the dog, it has rarely been used for this purpose in the rat. A method resembling the reservoir technique developed by Wiggers and Werle (1942) for the dog using blood pressure as the criterion has been modified for use with the rat. Male Sprague-Dawley rats weighing approximately 400 gm. were used. In the standardization of this technique the blood pressure was reduced to 30 mm. Hg in a 10-min. period of hemorrhage and then maintained at this level by subsequent small hemorrhages into the reservoir until reinfusion indicated the beginning of vascular collapse, at which time all the blood in the reservoir was returned. Considering that those animals which lived longer than 48 hr. were survivors, in a series of 27 animals, 21 died and 6 survived—a mortality rate of 78%.During the hypotensive period there was a consistent and steady drop in the respiratory rate and rectal temperature. The heart rate declined initially and tended to recover as the hypotensive period progressed. After reinfusion the blood pressure rose but. did not reach prehemorrhage levels. Hemorrhage into the bowel and convulsions were significant postreinfusion findings. |
