Pre-stress carbohydrate solution prevents fatal outcome after hemorrhage in 24-hour food-deprived rats

Twenty-four-hour food deprivation increases mortality after experimental hemorrhage. Survival after hemorrhage is closely related to the capacity of the animal to develop hyperglycemia. In this study, 24-h food-deprived rats were subjected to hemorrhage over a period of 75 min, standardized to reach a final blood pressure of 45 mmHg. Just prior to hemorrhage, the rats ingested a carbohydrate solution (n = 8) 2.16 mL/100 g body weight (b.wt.) or the same volume of water sweetened with sodiumsaccarinate (n = 7). A third group (n = 8) received an i.v. infusion of 5% glucose 0.5 mL/100 g b. wt. to mimic the hyperglycemia during hemorrhage of rats taking carbohydrates before stress. During hemorrhage rats treated with oral carbohydrate and i.v. glucose developed moderate hyperglycemia while glucose levels fell in water-treated rats (P < 0.001). Concomitant developments in hematocrits indicated improved plasma refill in carbohydrate- and glucose-treated animals versus controls (P < 0.05). There were no significant differences in blood pressure by the end of hemorrhage. Six of the seven animals treated with water died within 2 h of bleeding. In both the carbohydrate- and the glucose-treated groups 7 of 8 animals recovered and survived the 7-d observation period (P < 0.05 versus controls). It is concluded that oral carbohydrate solution before hemorrhage can alter the outcome after experimental hemorrhage. The similar finding in rats given i.v. glucose suggests that the key factor for survival was the capacity to mount a state of hyperglycemia during hemorrhage.