Influence of species,age and weight on the establishment of a murine model of brachial plexus root avulsion

BACKGROUND： Animal models of brachial plexus root avulsion are required for the study of brachial plexus root injuries. The established ventral approach results in slight injuries, and is similar to mechanisms underlying human brachial plexus root avulsion.OBJECTIVE： To analyze the effects of weight, age, and species on the success rate of brachial plexus root avulsion, and to determine the perfect method for establishing models of brachial plexus root avulsion.DESIGN, TIME AND SETTING： A randomized, block design was performed at the Laboratory of Professor Lihua Zhou, Zhongshan School of Medicine, Sun Yat-sen University, China from June 2008 to June 2009.MATERIALS： Sprague Dawley （SD） rats, golden hamsters, and BALb/C mice were used in the present study.METHODS： All animals were randomly subjected to classical brachial plexus root avulsion and modified brachial plexus root avulsion.MAIN OUTCOME MEASURES： Success rate of brachial plexus root avulsion. RESULTS： The success rate of brachial plexus root avulsion was greater in the modified group than in the classical group （P〈0.01）. Moreover, the difference was significant in 15-day-old SD rats, 5-week-old SD rats, and 3-month-old BALb/C mice （P〈0.01）. The success rate of brachial plexus root avulsion was greater in the same weight, 15-day-old juvenile SD rats, than in the 3-month-old BALb/C mice （classical group, P〈0.01; modified group, P〈0.05）. The success rate of brachial plexus root avulsion was significantly greater in 3-month-old golden hamsters than in 5-week-old SD rats in the classical group （P〈0.05）. The success rate of brachial plexus root avulsion was significantly lower in the 15-day-old SD rats compared with the 5-week-old and 3-month-old SD rats in the classical group （P〈0.01）. However, there was no significant difference in the success rate of brachial plexus root avulsion between various ages of SD rats in the modified group （P〉0.05）.CONCLUSION： Modified surgery to induce brachial plexus root avulsion significantly increases the success rate of model establishment. Species, age, and weight affect the success rate of brachial plexus root avulsion, and species plays an important role in the success rate.

Anesthetic management of a child with double outlet right ventricle and severe polycythemia: A case report

BACKGROUND Double outlet right ventricle(DORV)is a rare and complex congenital heart defect,and the surgical repairs vary with type and pathophysiology consequences.Due to prolonged progressive hypoxemia,severe polycythemia is common in patients with DORV,which ultimately leads to coagulation dysfunction and increases the risk of thrombosis and infarction.Consequently,the anesthetic management is challenging and how to manage severe polycythemia and avoid hypoxia-related complications in such patients is of great significance.CASE SUMMARY Herein,we report the anesthetic management of a 10-year-old female patient with a DORV.She lived in the low-oxygen Qinghai-Tibet Plateau,and presented with severe polycythemia(hemoglobin,24.8 g/dL;hematocrit,75%).She underwent a modified Fontan surgery,which was satisfactory and without any perioperative complications.Our anesthetic management highlights the importance of perioperative hemodilution in decreasing the risk of thromboembolism and the importance of correcting coagulopathy in preventing hemorrhage.CONCLUSION Anesthetic management is challenging in rare cyanotic congenital heart disease patients with severe polycythemia.It is important to adopt perioperative hemodilution and correction of coagulopathy in preventing thrombosis and hemorrhage.