ABSTRACT
To study the role of endothelin(ET) in the pathogenesis of traumatic shock. Multiple injuries involving the leg bones, the soft tissue and hemorrhage in Sprague Daulay rat were produced by smashing its legs on both sides to induce traumatic shock. Dynamic changes in plasma ET, arterial blood gas analysis (ABGA) and oxygen partial pressure in tissues including skeletal muscles,liver and small intestine were detected at pre trauma and post shock periods. Meanwhile, hemodynamic parametars of the rats and their survival time were monitored and recorded. The data showed that plasma ET levels increased significantly after traumatic shock, reaching a peak of about 2 5 times of normal levels. There was statistically significant difference of ABGA values and tissues oxygen partial pressure between pre trauma and post shock periods. Metabolic acidosis appeared during traumatic shock. The changes in oxygen partial pressure in liver and small intestine were more significant than that of skeletal muscles. The data suggested that the significant increase in plasma ET contents after traumatic shock, might plays an important role in maintaining the blood pressure in the earty stage of shock, but might be an important cause of death in the late stage. The irreversible decrease in oxygen partial pressure in internal organs might be the key factor of refractoriness to resuscitation in an late stage of shock
ABSTRACT
The aim of this study was to investigate the significance of low blood pressure (permissive hypotension) resuscitation in the treatment of uncontrolled traumatic shock. A traumatic shock animal model was replicated in Sprague Dawlay rats, the animals were randomly devided into non resuscitation group, traditional resuscitation group and low blood pressure resuscitation group. Prothrombin time(PT), activated pactial thromboplastin time(APTT) and oxygen partial pressure in tissues, including skeletal muscles, liver and small intestine, were determined before and after shock. Meanwhile, hemodynamic parameters of the rats and their survival time were monitored and recorded. The data showed that there were statistically significante difference in PT, APTT and amount of blood loss during shock between traditional resuscitation group and the other two groups. Low blood pressure (permissive hypotension) resuscitation could significantly improve oxygen partial pressure in tissues and prolong the mean survival time. The data suggested that low blood pressure resuscitation was a more rational strategy to improve the prognosis in rats with uncontrolled traumatic shock than traditional resuscitation strategy.
ABSTRACT
In order to investigate the dynamic changes in nitric oxide synthase (NOS) activity in organs during traumatic shock and to evaluate the effects of inhibitor of NOS and L Arginine (L Arg) on traumatic shock, rat model of traumatic shock was established, and the constitutive NOS and inducible NOS in the heart, small intestine, liver, lung , spleen were measured 0 5h, 3h, 5h after traumatic shock. Followed by intravenous injection with aminoguanidine (AG ), N G nitro L arginine methyl ester (L NAME), or L Arg, NOS were again measured, and the survival time and 24h survival rate were recorded. It was found that in normal rats cNOS was expressed in all organs, but only a weak iNOS expression in lung and liver. Half an hour after shock, cNOS was elevated in almost all organs in various degrees but there was no change in iNOS. 3h after shock, an increase in iNOS activity and a decrease in cNOS were observed. The iNOS was synthesized in large quantity 5h after shock. AG and L Arg markedly prolonged the survival time but L NAME did not in shock rats. AG inhibited the activity of iNOS but promoted the synthesis of cNOS, and both NOS were inhibited in L NAME group, but not in L Arg group. The results that iNOS was synthesized in large quantity only at later period of traumatic shock. To treat shock, the inhibitors of NOS and L Arg should be given according to the degree of shock, the dosage of drugs, and the time of administration
ABSTRACT
To study the dynamic changes and the significance of oxygen partial pressure in tissues in rats with traumatic shock, a traumatic shock model in Sprague Dawley rats were reproduced by limbs wounding, and oxygen partial pressure in tissues, including skeletal muscles,liver and small intestine, were assayed before trauma and after shock based on oxygen dependent quenching. Meanwhile, hemodynamic parameters of the rats were monitored. The results showed that oxygen partial pressure in tissues decreased significantly after traumatic shock( P