Reseach About The Changes Of Aldosterone And Angiotensin Ⅱ In Patients With Severe Head Injury Complicating Hypernatremia

Objective: The goal of this research was to evaluate the changes of sero-aldosterone and plasma-angiotensinⅡin patients with severe head injury complicating hypernatremia, trying to explore the significance of sero-aldoterone and plasma-angiotensinⅡin the mechanisms of severe head injury complicating hypernatremia.Methods: Twenty patients, admitted to SICU, with severe head injury, GCS Score≤8, complicating hypernatremia--defined as a serum sodium concentration of >or=to155 mmol/L or more(hypernatremia cohort)and other twenty patients who were also undergoing severe head injury but without hypernatremia (nonhypernatremia cohort) were studied, excluded hypovolemia hypernatremia and excessive ingestion of natrium. Twenty healthy person (normal controls) were also studied. Radio immunoassay was used to determine the levels of sero-aldosterone and plasma-angiotensinⅡof venous blood from the three Cohorts above. All blood preparation was drawn in decubitus before foodintake. The sexualities, ages, liquid intakes, output volumes, CVPs and GCS Scores of all patients and the controls were also recorded in this study. Measurement datas were denotated with(x±s), ANOVA or Rank-Sum Test or Chi-square Criterion was used when disparations among the three grops were studied. We also applied Linear correlation or Rank correlation to analys the correlations between the levels of sodium and the levels of plasma-angiotensin, the values of plasma-angiotensin and the levels of sero-aldoterone.Results: Compared with the normal controls,the levels of plasma-angioten- sinⅡfrom the hypernatremia cohort and the nonhypernatremia cohort were significantly increased(P<0.01), the levels of plasma-angiotensinⅡfrom the hypernatremia group increased more obviously, about 3～6 times of the normal controls′and 2～3 times of the nonhypernatremia cohort. And a positive correlation(r=0.65, P<0.01) betweet the levels of sodium and the levels of plasma-angiotensin was also observed. But no significant disparation from the levels of sero-aldoterone(P>0.05) could be observed among the three cohorts.Conclusion: Hypernatremia in severe head injury is significantly relevant to the increase in the levels of plasma-angiotensinⅡ, and plasma-angiotensinⅡmay be one of the neurohumor mechanisms of severe head injury complicating hypernatremia. There was a dissociation of between angiotensinⅡand aldosterone that the concentration of aldosterone didn′t elevated with the increase in the concentration of angiotensin in all patients that undergoing severe head injury. Maybe aldosterone was not involed in the neurohumor mechanisms of hypernatremia in severe head-injuried patients.