Effect of cervical sympathetic ganglia block on the mortality of mice with combined radiation and burn injury and its possible mechanism / 中国组织工程研究

ABSTRACT

BACKGROUND: Cervical sympathetic ganglia block accelerates the re covery of the homeostasis of organic nervous-endocrine-immune system, butit is still unclear whether it can suppress the imbalance of homeostasis in duced by post-traumatic stress disorder. OBJECTIVE: To observe the effect of cervical sympathetic ganglia blockon the mortality of mice with combined radiation and burn injury, andwhether it can become an easy and effective method to treat secondarydamage after serious trauma. DESIGN: A randomized grouping design, an animal controlled experiment. SETTING: Department of Anesthesiology, Guangzhou General Hospital, Guangzhou Military Area Command of Chinese PLA.MATERIALS The experiments were carried out in the Institute of Combined Injury, the Third Military Medical University of Chinese PLA between February 2004 and July 2005. Totally 160 Kunming mice were randomly divided into control group (n=50) and cervical sympathetic ganglia block group (n=50). In the control group, the mice were only induced to models of combined radiation and bum injury, and treated with injection of 0.3 mL saline at cervical part. In the cervical sympathetic ganglia block group, the mice were induced to models of combined radiation and burn injury, and then treated with cervical sympathetic ganglia block, once a day for 14 days continuously.METHODS: Methods to induce injury in the animals ① Radiation injury The mice were given even radiation of 60Coγ ray (5 Gy) at a distance of 1.5 m to the whole body, the rate of absorptive dosage was (5.17-5.33) mGy/s. ② Burn injury After the radiation injury, coagulated gasoline was smeared on the back and burnt for 8 s to induce degree Ⅲ burn injury of 15% of the total body surface, which was proved by the pathological section. Methods of cervical sympathetic ganglia block Cervical sympathetic ganglia block was given bilaterally, and then the mice were injected with 0.2 mL lidocaine (5 g/L), and it was observed whether the symptoms similar to Horner syndrome (hyperemia of conjunctiva, drooping eyelid,blushing, smaller eyeslit) occurred or not at 5 minutes after injection.MAIN OUTCOME MEASURES: The mortality at 2, 5, 7, 10, 20 and30 days after injury and the changes of the numbers of red blood cells,white blood cells and blood platelet in peripheral blood at 7, 14 and 21 days after injury were observed in both groups. The effects of cervical sympathetic ganglia block on the levels of tumor necrosis factor-alpha (TNF-α),interleukin-1β (IL-1β) and interleukin-6 (IL-6) in serum at 3, 6 and 14days after combined radiation and burn injury were also observed.RESULTS: All the 160 mice were involved in the analysis of results without deletion. ① Compared with the control group, the mortalities at 5,7, 10, 15, 20 and 30 days in the cervical sympathetic ganglia block group were significantly decreased [control group 8%, 22%, 32%, 54%, 74%,82%, 90%; cervical sympathetic ganglia block group 8%, 14%, 16%, 22%,28%, 34%, 56%]. ② Compared with the control group, the numbers of red blood cells, white blood cells and blood platelets in peripheral blood at 7,14 and 21 days after injury in the cervical sympathetic ganglia block group were significantly increased [at 21 days red blood cells 23.21×1012 L-1, 14.58×1012 L-1; blood platelet 16.87×1011 L-1, 12.57×1011 L-1; white blood cells 20.65×109 L-1, 14.58×109 L-1]. ③ The levels of TNF-α, IL-1β andIL-6 in serum at 3, 6 and 14 days after injury in the cervical sympathetic ganglia block group were significantly decreased as compared with those in the control group [at 14 days TNF-α 189, 365 ng/L; IL-1β 14, 23 ng/L;IL-6 70, 132 ng/L].CONCLUSION: Cervical sympathetic ganglia block can significantly decrease the mortality of animals with combined radiation and burn injury,and it is an easy and effective method to treat serious trauma, and the mechanism may be realized through accelerating the recovery of hematopoietic function and suppressing the excessive inflammatory reaction.