1 Department of General Surgery, Affiliated Hospital of Jiangsu University, Zhenjiang, China.
2 Division of Gastrointestinal Surgery, Department of General Surgery, The Affiliated Huai'an Hospital of Xuzhou Medical University, Huai'an Second People's Hospital, Huai'an, China.
3 Department of Anesthesiology, People's Hospital of Lianshui County, Huai'an, China.
4 Department of General Surgery, Affiliated Hospital of Jiangsu University, Zhenjiang, China. zhouqingzy@163.com.