无静脉补液条件下失血性休克犬早期口服补液对循环氧动力学指标的影响

目的研究犬40%血容量失血后早期口服补液对循环氧动力学指标的影响。方法毕格犬20只,先期无菌手术行颈动、静脉置管,24小时后按全身血容量的40%放血制作失血性休克模型。随机分为不补液组(n=8)、口服补液组(n=6)和静脉补液组(n=6)。失血后第1个24小时不补液组无治疗,口服补液组和静脉补液组分别从胃内或静脉输入3倍失血量的葡萄糖-电解质溶液。失血后24小时起3组均给予静脉补液。测定动物非麻醉状态下的平均动脉压(MAP)和血细胞比容(HCT),抽取动脉和混合静脉血测定动、静脉氧分压和血氧含量(CvO2)、计算氧供量(DO2)和氧耗量(VO2),并统计3天死亡数。结果失血后3组犬MAP、PaO2、DO2和VO2均显著降低,PaCO2显著升高。两补液组上述指标迅速恢复,失血后72小时PaO2、PaCO2和pH均恢复至失血前(0小时)水平,但DO2和VO2仍低于0小时水平。口服补液组MAP、PaO2和pH恢复明显优于不补液组,但差于静脉补液组;PaCO2的变化与之相反。口服补液组DO2失血后4、8、24小时显著高于不补液组,但24小时后低于静脉补液组(均P0.05);VO2失血后4小时起显著高于不补液组,但低于静脉补液组(均P0.05)。不补液组8只犬72小时死亡5只,口服补液组6只犬死亡2只,而静脉补液组无一死亡。结论40%血容量失血后早期口服补液能显著改善循环氧动力学指标,减轻组织低氧和代谢障碍,有助于改善动物的早期存活。

Effects of early oral fluid resuscitation on circulatory oxygen dynamic parameters in dogs subjected to loss of 40% total blood volume

Objective To investigate the effect of early oral fluid resuscitation on circulatory oxygen dynamic parameters in dogs subjected to loss of 40% total blood volume. Methods Twenty Beagle dogs with intubation of carotid artery and jugular vein for 24 hours were subjected to loss of 40% total blood volume, then were divided into non fluid resuscitation （ NR, n = 8 ） , oral resuscitation （ OR, n = 6 ） and intravenous resuscitation （ IR, n = 6 ） groups. Dogs in IR and OR groups were given 3 times volume of blood loss of glucose-electrolyte solution （ GES ） by gastric or intravenous infusion in the first 24 hours after bleeding, while those in NR group were not given any treatment. Dogs in each group were given intravenous fluid resuscitation 24 hours post hemorrhage （ PH ）. The mean arterial pressure （MAP） was determined. Blood gas analysis was evaluated for PaO2 ,PaCO,oxygen delivery（ DO2 ） and ox- ygen consumption （ V02 ） before 0 hours and at 2,4,8,24,48 and 72 hours post hemorrhage. Results Hemorrhage resulted in a significant decrease in MAP, PaO2 , DO2 and VO2, and an increase in PaCOz of three groups （ P 〈 0. 05 ）. The measurements of two resuscitation groups returned gradually to the pre-hemorrhage levels at 72 hours, while DO2 and V02 still lowered compared with those at 0 hours（ P 〈0.05）. The measurements of MAP,PaO2 and pH of OR group were significantly superior to those of NR group,but inferior to those of IR group. DO2 levels of OR group were significantly higher than those of NR group at 4,8 and 24 hours, but lower than those of IR group （ all P 〈 0.05 ）. VO2 levels of OR group were markedly higher than those of NR group 4 hours following hemorrhage, but lower than those of IR group （ P 〈 0.05 ）. At 72 hours after hemorrhage, five of 8 dogs died in NR group, two of 6 in OR group and none in VR group. Conclusion The results indicate that early oral fluid resuscitation improves oxy- gen dynamic parameters,alleviates tissue hypoxia and promotes early survival of animals subjected to severe hemorrhagic shock.