Objective To study the effects of hypotensive resuscitation and larger volume fluid resuscitation on uncontrolled hemorrhagic shock and survival in rats with a standardized massive splenic injury model（MSI）.Methods Following the MSI model,fifty Wistar rats were randomly and equally divided into five groups,group 1:sham-operated group,group 2: shock untreated group,group 3:normal MAP resuscitation group（during acute resuscitation phase MAP was kept at 80 mm Hg）,group 4:Hypotensive resuscitation group（during acute resuscitation phase MAP was kept at（60±5） mm Hg）,and group 5:larger volume fluid resuscitation with hypotensive resuscitation group(during acute resuscitation phase MAP was kept at（60±5） mm Hg,simultaneously infused SNP at 5 μg·kg-1·min-1).Results The mean survival time in group 1～5 was 180 min,73.50 min±8.04 min,114.30 min±31.33 min,146.70 min±28.07 min and 171.60 min±15.74 min respectively.Statistic significances were seen in each group（P<0.05）,except between group 1 and group 5（P=0.0671）.The amount of bleeding in group 2～5（during acute resuscitation phase） was 3.79 ml/kg±1.39 ml/kg、17.41 ml/kg±8.88 ml/kg、8.67 ml/kg±4.59 ml/kg and 10.33 ml/kg±4.31 ml/kg respectively.The loss of blood in group 3 was significantly more than other groups（P<0.05）.Group 4 and 5 enhanced the blood loss significantly compared with group 2（P<0.05）.The histopathologic of liver and renal showed that histopathologic injury is severe in group 3 compared with group 4,and histopathologic injury is not in evidence in group 5.Conclusion Hypotensive resuscitation and adding SNP at proper dose additionally could improve tissue metabolism and prolong survival time during hypotensive resuscitation from uncontrolled hemorrhagic shock.It is a more ideal resuscitation method compared with normal blood pressure resuscitation.
Objective To evaluate the influence of hypothermia to Ca 2+/calmodulin-dependent kinase Ⅱ during global brain ischemia in rats. Methods Fifteen male SD rats were randomly divided into 3 groups: control group (group Ⅰ, n=5), hepothermia group (group Ⅱ, n=5) and reperfusion group (group Ⅲ, n=5). Only sugery was performed without hypothermia and clipping bilateral carotids in group Ⅰ. Ice was used covering head of rats in group Ⅱ to get hypothermia around 32℃, and bilateral carotids were clipped 20 min of ischemia followed by 60 min reperfusion keeping tympanum temperature 32℃. Bilateral carotids were clipped 20 min of ischemia followed by 60 min reperfusion without hypothermia in Group Ⅲ. Brain tissues were saved in three groups after experiments for evaluating Ca 2+/calmodulin-dependent kinase Ⅱ. Results Left tympanum temperature in the group Ⅱ is significantly lower than group Ⅰ during global ischemia and reperfusion(p<0.05). Those are no difference between group Ⅰ and group Ⅲ. The activity of Ca 2+/calmodulin-dependent kinase Ⅱ after 60 min reperfusion in both Group Ⅱ and group Ⅲ was significantly lower than those in the group Ⅰ(P<0.05), which is significantly higher in the group Ⅱ than in the group Ⅲ(P<0.05). Conclusion Hypothermia can increase the activity of Ca 2+/calmodulin-dependent kinase Ⅱ after global ischemia reperfusion. Hypothermia has significant protection during ischemia reperfusion injury.
