title: Mediastinal micro-vessels clipping during lymph node dissection may contribute to reduce postoperative pleural drainage.
abstract: BACKGROUND
  Postoperative pleural drainage markedly influences the length of postoperative stay and financial costs of medical care. The aim of this study is to retrospectively investigate potentially predisposing factors related to pleural drainage after curative thoracic surgery and to explore the impact of mediastinal micro-vessels clipping on pleural drainage control after lymph node dissection.
  
  
  METHODS
  From February 2012 to November 2013, 322 consecutive cases of operable non-small cell lung cancers (NSCLC) undergoing lobectomy and mediastinal lymph node dissection with or without application of clipping were collected. Total and daily postoperative pleural drainage were recorded. Propensity score matching (1:2) was applied to balance variables potentially impacting pleural drainage between group clip and group control. Analyses were performed to compare drainage volume, duration of chest tube and postoperative hospital stay between the two groups. Variables linked with pleural drainage in whole cohort were assessed using multivariable logistic regression analysis.
  
  
  RESULTS
  Propensity score matching resulted in 197 patients (matched cohort). Baseline patient characteristics were matched between two groups. Group clip showed less cumulative drainage volume (P=0.020), shorter duration of chest tube (P=0.031) and postoperative hospital stay (P=0.022) compared with group control. Risk factors significantly associated with high-output drainage in multivariable logistic regression analysis were being male, age >60 years, bilobectomy/sleeve lobectomy, pleural adhesion, the application of clip applier, duration of operation ≥220 minutes and chylothorax (P<0.05).
  
  
  CONCLUSIONS
  This study suggests that mediastinal micro-vessels clipping during lymph node dissection may reduce postoperative pleural drainage and thus shorten hospital stay.
authors.affiliation: 1 Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Thoracic Surgery II, Peking University Cancer Hospital & Institute, Beijing 100142, China ; 2 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia.
authors.forename: Shi
authors.initials: S
authors.lastname: Yan
authors.affiliation: 1 Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Thoracic Surgery II, Peking University Cancer Hospital & Institute, Beijing 100142, China ; 2 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia.
authors.forename: Xing
authors.initials: X
authors.lastname: Wang
authors.affiliation: 1 Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Thoracic Surgery II, Peking University Cancer Hospital & Institute, Beijing 100142, China ; 2 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia.
authors.forename: Chao
authors.initials: C
authors.lastname: Lv
authors.affiliation: 1 Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Thoracic Surgery II, Peking University Cancer Hospital & Institute, Beijing 100142, China ; 2 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia.
authors.forename: Kevin
authors.initials: K
authors.lastname: Phan
authors.affiliation: 1 Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Thoracic Surgery II, Peking University Cancer Hospital & Institute, Beijing 100142, China ; 2 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia.
authors.forename: Yuzhao
authors.initials: Y
authors.lastname: Wang
authors.affiliation: 1 Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Thoracic Surgery II, Peking University Cancer Hospital & Institute, Beijing 100142, China ; 2 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia.
authors.forename: Jia
authors.initials: J
authors.lastname: Wang
authors.affiliation: 1 Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Thoracic Surgery II, Peking University Cancer Hospital & Institute, Beijing 100142, China ; 2 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia.
authors.forename: Yue
authors.initials: Y
authors.lastname: Yang
authors.affiliation: 1 Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Thoracic Surgery II, Peking University Cancer Hospital & Institute, Beijing 100142, China ; 2 The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia.
authors.forename: Nan
authors.initials: N
authors.lastname: Wu
keywords: Lung cancer; cumulative drainage volume; postoperative