Transrectum Endoscopic Surgery Of Hirschsprung’s Disease With Traditional Colonoscope In A Porcine Survival Model

ObjectiveHirschsprung’s disease（HD）is a common congenital gastrointestinal malformation disease in children,with a prevalence of 1:500¹:2000,male and female ratio of 4:1.Once HD is diagnosed,the conservative treatment always fail,most of which require surgical treatment.But all kinds of surgical methods have specific defects and complications,and the postoperative complications are as high as 20%³0%.Along with the development of surgical instruments,a large number of scholars and experts engaged in reducing the occurrence of surgical complications by improving all kinds of operation methods,including transanal pull-through surgery,laparoscopic pull-through procedure and Natural Orifice Transluminal Endoscopic Surgery（NOTES）and single-incision laparoscopic surgery（SILS）^[1-2].Among these operative methods,Natural Orifice Transluminal Endoscopic surgery（NOTES）is regarded as an excellent progress in the development of minimally invasive surgery.Most pediatric surgerons are demonstrating for their best efforts at this hotspot because of no management of anterior abdominal wall,easy to care,more efficient for society and other potential advantages comparing to traditional surgery and laparoscopic surgery^[3-5].This study is based on the mini porcine survival model to compare the outcome of colon resection operation,postoperative recovery and the cardiopulmonary function of experimental animals and the effects of immunological stress between transrectum endoscopic procedure and laparoscopic prodedure promoted.Then we evaluate the feasibility of the interest operation method,and analyze the physiologic impact of NOTES.It provides practical experience,theoretical basis and clinical application for the further development of NOTES in the treatment of children with Hirschsprung’s Disease.MethodIn this experiment,20 female minipigs in the age of 3-6 months were selected,and their weights between 25kg and 30kg.The minipigs were divided into two groups randomly,Group A and Group B.Transrectum endoscopic procedure with traditional colonoscope was implemented in the experimental animals of Group A,and laparoscopic procedure implemented in the minipigs of Group B.We record the operation time,the length of colon resected and dissociated（the ratio which were calculated according to the length）,preoperative,intraoperative and postoperative electrocardiogram parameters.We extract the venous blood of fasting animals preoperatively,postoperatively,at the first,second,third 24-hour postoperatively.The stress and immune indicator of these blood sample were detected,which included white blood cells,neutrophils ratio,cortisol,tumor necrosis factor（TNF）,interleukin–1（IL-1）,and immune indexes（IgA,IgG,IgM,C3 and C4）.ResultsAll operation procedure were accomplished successful.All of the 20 experimental animals survived without serious postoperative complications.In both groups,the colons were resected and pulled down to the anus without tension,and then anastomosis were accomplished.There was no significant difference between the two groups in the length of colon resected and dissociated（P>0.05）,and it was not significantly different that include the ratio of colon resected,colon dissociated to total colon,and in the ratio of colon resected to colon dissociated（P>0.05）.The second phase operative time have obvious difference between two groups（P<0.05）,and the time for mesocolon-excision procedure,the dissociating-rectal time per centimeter were significantly different between the two groups（P<0.05）.There was no significant difference between the two groups in cardiopulmonary function index each time node.The cardiac rhythm and respiratory rhythm of all experimental animals were stable during the perioperative period.The white blood cells,neutrophils,tumor necrosis factor and interleukin-1,cortisol and other stress indexes of experimental animals rise rapidly,and cortisol peaks appear immediately after surgery.Other indicators peak appeared on postoperative days 1,then fell back quickly.There was significant difference in tumor necrosis factor in perioperative stress index（P<0.05）.The immune index of the experimental animals immediately dropped to the lowest level after the operation,and then began to recover.Conclusion1.Transrectum endoscopic surgery with traditional colonoscope and megacolon radical laparoscopic procedure can complete megacolon radical operation,but during operation process,part of the colonoscopic procedure expended more time significantly,and they were more difficult to operate.2.The immune function of the body is inhibited by the radical operation of colonic colonoscopy.Compared with laparoscopic assisted operation,immune stress index of experimental animal between groups almost did not have obvious difference.It suggests that the endoscopic procedure did not reduce the trauma of experimental animals,but perioperative complications of the experimental animal and mortality is not increased.3.The perioperative tumor necrosis factor and operation time was significantly higher than laparoscopic assisted group.It may have to do with the bigger pneumoperitoneum pressure fluctuation established by endoscope,difficult spatial orientation,and lack of special equipment and so on.