放射损伤、烧伤与放烧复合伤早期心功能变化的离体实验研究

Experimental Studies on the Cardiac Function in Vitro in the Early Stage of Radiation, Burn and Combined Radiation burn Injuries

目的：探讨放射损伤复合烧伤心功能抑制加重的机理．方法：采用离体心脏灌流法，测定伤后６小时离体心脏固有收缩功能的变化及伤后血清对正常离体心功能的影响．结果：（１）放烧复合伤后离体心功能收缩与舒张功能的抑制轻于烧伤，与复合伤后在体心功能抑制重于烧伤的复合效应不一致；（２）伤后补液可在一定程度上缓解心脏固有收缩功能降低的程度；（３）伤后加维拉帕米对烧伤与复合伤后心肌固有收缩功能的影响不一致；（４）复合伤血清对正常离体心功能的抑制强于单一伤血清，且强于烧伤血清及放射伤血清混合的作用．结论：放烧复合伤对在体心功能抑制加重的复合效应与复合伤后血容量丧失更重及血清成分对心功能抑制强于单一伤有关，而与伤后心肌固有收缩功能的影响关系不大．

Aim: To explore the mechanism of cardiac function supression following radiation, burn and combined radiation burn injuries. Methods: Changes of cardiac intrinsic contractility six hours after radiation, burn and combined radiation burn injury and the effects of serum from the injury groups on the normal heart in vitro were studied by cardiac perfusion in vitro. Results: (1)Burn or combined radiation burn injury caused the decrease of cardiac intrinsic contractility. Opposite to the combined effect in vivo, the depress of cardiac function in vitro following combined radiation burn injury was not as severe as that after burn. (2)With replenishing fluid, the cardiac intrinsic contractility was improved to a certain degree in the burn and combined radiation burn group. (3) Verapamil improved the cardiac function in vitro after burn, but had no effect in the combined radiation burn group. (4)Serum from the burn and combined radiation burn injury groups depressed cardiac function in vitro. The effect of serum from combined radiation burn injury was stronger than that from burn. It was also stronger than the admixture of serum from irradiation and burn injuries. Conclusion: The components of serums from different groups are different, and the components of serum from combined injury is not equal to that from radiation injury and burn. The changes of serum components is likely to be one of the main causes of combined effect in cardiovascular function following combined radiation burn injury, and the changes of intrinsic contractility may not be the main reason in exaggerating depress of cardiac function in vivo postinjury.