Abstract: AIM: To investigate the effects of arginine vasopressin (AVP) on uncontrolled hemorrhagic shock in rats when used during the pre-hospital period.METHODS: One hundred and twenty SD rats were divided into 5 groups: hypotensive resuscitation control group, AVP (1×10^-4, 5×10^-4, 1×10^-3 and 5×10^-3 U/mL) with hypotensive resuscitation groups. Uncontrolled hemorrhagic shock model was adopted, then shock rats were resuscitated with lactated Ringer's solution/hydroxyethyl starch with or without four doses of AVP (the blood pressure was maintained at 50 mm Hg for 3 h, to mimic the pre-hospital treatment period). At the end of hypotensive resuscitation stage, the bleeding was controlled and rats received fluid resuscitation to maintain the blood pressure at 80 mm Hg for 2 h (the definitive treatment period). The effects of early treatment with AVP on blood loss, fluid requirement, animal survival and hemodynamics in uncontrolled hemorrhagic shock rats were observed.RESULTS: As compared with the hypotensive resuscitation control group, application of AVP reduced the blood loss and fluid requirement during the entire treatment period. And AVP also increased the survival time and 24-h survival rate of shock rats, and improved the hemodynamic parameter of shock rats including left intraventricular systolic pressure (LVSP) and maximal change rate of left intraventricular pressure (±dp/dt_max). The best effect was shown with 5×10^-4 U/mL of AVP.CONCLUSION: Early administration of AVP to maintain the blood pressure during the pre-hospital period has good beneficial effect on uncontrolled hemorrhagic shock rats.

Key words: uncontrolled hemorrhagic shock, arginine vasopressin, hypotensive resuscitation, pre-hospital treatment