LIU Yin-Qiu, LI Bing-Cang,LI Shu-Guang
(Department of Aeronautic Dynamics, Faculty of Aerospace and Aviation Medicine, Fourth Military Medical University, Xi'an 710033, China)
SUN Xi-Qing
(Institute of FieldSurgery, Third Military Medical University, Chongqing 400042, China)

CLC number: R826.63 Document code: A
Article ID：1000-2790(2000)05-Cover2-01

INTRODUCTION

With thedevelopment of modern weapons, there have been an increasing number of wounds of shell,grenade and landmine. It has been reported that in modern wars thoracic shell wounds weremore frequently seen than thoracic gunshot wounds. Of the former, 80% resulted in earlydeath^[1,2] . Therefore, it isextremely important to strengthen the research on early treatment of thoracic shell woundsso as to improve field trauma treatment. Up to now, there have been no big animal model ofthoracic shell wounds and little literature of experiments on thoracic shell wounds^[1,2] for researchers and surgeons to takeadvantage of. Based on our previous research^[3] , we have constructed three different dog models ofthoracic shell wounds and investigated the causes of the early death and the effects ofthe early treatment of the models.

MATERIALS AND METHODS

Thirty-eighthybrid dogs were selected as experimental animals. After anesthetization, a 0.4 g steelball was shot with a musket into each dog's right lower chest, causing a wound perforatingits right chest. The dogs were randomized into three groups depending on their differentdosages of filling: Group A (n=8), group B (n=17) and group C (n=13), with an inletvelocity (m^. s^-1 ) of 983±87, 827±78 and 649±92 respectively. Eachgroup was further divided into a model group and a treated group.

RESULTS

①The transferring energies of groups A, B and C were found to be 176, 92 and 64 Joules respectively. However, with the decline in the inlet velocity and transfer-ring calories, the average survival time after the wound prolonged and curability increased (Tab 1). ②There was an increase in the instantaneous pressure at all the groups' air passage, trachea, pleural cavity, abdominal cavity, cardiac chambers, blood vessels including thoracic aorta, abdominal aorta and artery and superior vena cava. A direct ratio was observed of the incidence and the degree of traumatic shock to transferring energy. ③Hi-speed X-ray photography indicated a small and cast-shaped instantaneous cavity in the thoracic cavity and some splash at the inlet. ④Intercostal artery bleedingquickly resulted in massive hemorrhage and finally death. ⑤Early and extensive pulmonary hemorrhage and pneumochysistended to be the major causes of death 4～6 h after the wounding. Despite the removal of the woundedlung half an hour after the wounding, the occurrence and development of ALI, ARDS couldn'tbe prevented. The occurrence of pneumonic ARDS was characterized by its latency,progressiveness and involvement of the contralateral lungs. ⑥Early cardiac insufficiency and failure were also obvious, which was related to hemorrhage but not significantly.

Tab 1 Survival time of dogs of the groups after wounding

DISCUSSION

In thepresent study, we have constructed three dog models of thoracic shell wounds. Group Abeing the fatal model; Groups B and C, curable models. They might reflect a dose-effectrelationship between energy and the wounds^[4] . The major causes of early death of the wounded dogsincluded hemorrhagic and traumatic shocks; death after primary recovery was usually causedby respiratory failure and cardiac failure, the pathogenesis of which remains to beexplored. Early treatment can significantly extend the survival time of the wounded dogsbut the equipment and plans for the early treatment have to be further improved andperfected.

Editor YUAN Tian-Feng

Foundation Item: A key research project of the Army during the 9th Five-Year Plan period (96L046)
Biography: CAI Jian-hui (male, born in 1964), M.D., a resident physician in Department of Cardiothoracic Surgery, Xijing Hospital, Fourth Military Medical University. Tel. (029)3375311 Email. jianhui@hrd.xaonline.com

REFERENCES：

[1] 王正国， 朱佩芳. 第31届国际军事医学会议战伤论文综述[J]. 中华创伤杂志, 1997;13(1):55-56.
[2] 刘维永, 刘荫秋. 胸部火器伤实验与临床研究进展[J]. 中国胸心血管外科临床杂志, 1998;5(2):121-123.
[3] 郭建军, 刘维永, 蔡建辉. 家兔胸部火器伤实验模型建立及早期死亡原因探讨[J]. 中国胸心血管外科临床杂志, 1998;5(2):73-75.
[4] Fackler ML. Gunshot wound review[J]. Ann Emerg Med, 1996; 28(1):2-6.

Received date: 2000-02-08 ; Revised date: 2000-02-23 (CAI Jian-Hui,LIU Wei-Yong,GUO Jian-Jun；LIU Yin-Qiu, LI Bing-Cang,LI Shu-Guang；SUN Xi-Qing)