The Effect on Acute Lung Injury When 7.5% Hypertonic Saline-Hydroxyethyl Starch for Resuscitated Rats after Hemorrhagic Shock

ABSTRACT

PURPOSE: Acute lung injury/acute respiratory distress syndrome is common following major trauma, and is one of the most important causes of mortality and morbidity. Compared with gelatine, resuscitation with hydroxyethyl starch (HES) reduces posttrauma capillary leak. Furthermore, hypertonic saline (HTS) is known as a promising fluid resuscitation therapy with the potential to reduce lung injury caused by severe trauma. The aim of this study was to test the hypothesis that resuscitation with mixed fluids, HTS and HES, will reduce inflammation in hemorrhagic shock induced by acute lung injury compared to control (sham injury) or to either fluid alone. METHODS:Spraque-Dawley (SD) rats were divided into five groups randomly Group I were cannulated but not bled (sham); Group II bled and received Ringer's lactated solution; Group III bled and received 7.5% HTS; Group IV bled and received HES; Group V bled and received a mixeture of HTS and HES (HTS-HES). After anesthetizing the rat, two catheters were inserted into femoral vessels the femoral artery for monitoring blood pressure and pulse rate; the femoral vein for bleeding and fluid resuscitation. Blood sampling was done for arterial blood gas analysis (ABGA), Tumor necrosis factor-alphaTNF-alpha, Interleukin-6 (IL-6) before shock, after fluid resuscitation and after 48 hours of survival. Bronchoalveolar lavage (BAL) and a lung histology study were conducted in surviving rats. RESULTS: Survival rates were as follows; Group I, 80%; Group II, 100%; Group III, 70%; Group IV, 70%; Group V, 100%. There were no significant between group differences in initial ABGA, hemoglobin, or TNF-alpha TNF-alphaevels postresuscitation were significantly higher in group II compared to groups IV and V. After 48 hours of survival, TNF-alphaas higher in groups IV and V than in group II. After survival, The IL-6 level of group V was significantly lower compared to that of the control group. IL-6 levels in BAL fluid were higher in groups IV and V than in groups I and II. Lung injury histology scores were significantly higher in groups IV and V than in the control group. CONCLUSION: After moderate hemorrhagic shock, lung injury is more severe in rats resuscitated with HTS-HES than in the control groups.