Influence of different volumes of fluid resuscitation on systemic oxygen metabolism and gastrointestinal oxygenation after hemorrhagic shock in dogs first entering high altitude

Objective:To evaluate the effect of fluid resuscitation of different volumes on DO2,VO2 and pHi after hemorrhagic shock in dogs at high altitude.Methods: A total of 18 adult dogs,first transported to the place of 3 780 meters above the sea level,were randomly divided into three groups(n = 6): group I underwent hemorrhagic shock,group II and III were infused the lactated Ringer's solution(LR) with 1.5,3 fold volume of blood loss respectively after hemorrhagic shock.The DO2I,VO2I,O2ER,pHi and PgCO2 were measured before and after blood letting,1 h after hemorrhagic shock and 20,60,120 min after fluid resuscitation,respectively.Results: To compare with the basic value,DO2I decreased 70% and VO2I decreased 60% at 1 h after the shock.The VO2I and DO2I were significantly increased after fluid resuscitation in group II and III,but the DO2I and VO2I were significantly lower in group III compared with that in group II at 2 h after fluid resuscitation(P0.05).The PgCO2 gradually increased and pHi reduced after hemorrhagic shock.PgCO2 and pHi recovered to the value before the shock at 20 min after fluid resuscitation.But the pHi was significantly lower at 60,120 min after fluid resuscitation in group II and III compared with the basic value.The pHi was significantly lower in group III compared with that in group II(P0.05).Conclusion: To improve systemic oxygen delivery and visceral perfusion,1.5 fold volume of fluid resuscitation is better than 3 fold.