烫伤大鼠休克期内不同时间切痂对心肌损伤的影响

Effects of escharectomy at different time points on myocardial damages in scalded rats during shock stage

目的 探讨烧伤后休克期内不同时间切痂对心肌损害的影响。方法 以大鼠 3 0 %TBSAⅢ度烫伤为模型 ,动物随机分为正常对照组 (N组 ,n =6) ,烧伤对照组 (C组 ,n =6) ,1、3、6、12、2 4和 3 6h切痂组 (n =6) ,各切痂组于伤后各时相点切痂 ,伤后 72h行血清肌酸激酶同工酶MB(CKMB)、天冬氨酸氨基转换酶 (AST)检测和心肌组织病理观察。结果 C组血清CKMB、AST浓度显著高于其余各组 ,心肌组织病理变化程度重 ,各切痂组血清CKMB、AST浓度随伤后切痂时间延长而逐渐升高 ,心肌病理改变逐渐加重 ,而l、3h切痂组与正常对照组比较改变不明显。结论 休克期切痂能有效防治烧伤后心肌损害 ,且切痂越早 ,效果越好。

Objective To investigate the effects of escharectomy at different time points on myocardial damages in scalded rats during shock stage. Methods A total of 42 rats were inflicted with 30% TBSA Ⅲ scalding on their backs and then randomly and equally divided into 7 groups: burned control group (C) and escharectomy groups at hour 1, 3, 6, 12, 24 and 36 postburn. Another 6 rats were employed as normal control (N). The serum levels of creatine kinase isoenzymes MB (CKMB), aspartate aminotransferase (AST) were determined and morphological changes in myocardial tissues were observed 72 hours after the burn. Results The serum levels of CKMB and AST were higher in the C group than in other groups, and the levels in escharectomy groups were increased along with the prolongation of scar cutting. Pathologically, the myocardial tissues were severely damaged in C group, and the later the scars were cut, the severe the damages were in the escharectomy groups except the 2 groups with scars cut at hour 1 and 3. Conclusion Escharectomy in shock stage can effectively prevent the damage of the myocardial tissues from postburn injury and the earlier it is performed, the better the result is.