title: Systemic and alveolar inflammatory response in the dependent and nondependent lung in patients undergoing lung resection surgery: A prospective observational study.
abstract: BACKGROUND
  Measurement of inflammatory mediators in bronchoalveolar lavage (BAL) during lung resection surgery with periods of one-lung ventilation (OLV) has revealed an intense local pulmonary response. The role of each lung in the inflammation that occurs during this procedure has never been investigated.
  
  
  OBJECTIVE
  The primary objective of our study was to compare the inflammatory response in the dependent lung with that of the nondependent lung by measuring inflammatory markers in BAL. Our secondary objective was to assess the behaviour of these inflammatory mediators in patients with and without postoperative pulmonary complications (PPCs).
  
  
  METHODS
  A prospective, observational study.
  
  
  METHODS
  Department of Anaesthesiology in a university hospital.
  
  
  METHODS
  Forty-six consecutive patients undergoing lung resection surgery.
  
  
  METHODS
  BAL samples were taken from dependent and nondependent lung 10 min before initiating OLV and at the end of OLV (once two-lung ventilation was established). All patients were followed up until 30 days after surgery.
  
  
  METHODS
  The concentration of cytokines [interleukin (IL)-1, IL-2, IL-6, IL-10, tumour necrosis factor-alpha (TNF-α)], nitric oxide, carbon monoxide and matrix metalloproteinase 2 (MMP-2) was analysed in both lungs before and after OLV. PPCs were recorded.
  
  
  RESULTS
  In BAL fluid, all measured biomarkers, apart from IL-10, were significantly greater (P < 0.05) at the end of OLV than those obtained before OLV, both for the dependent and nondependent lung. The increase in measured biomarkers was similar in both lungs. Eight patients developed PPC. Patients who developed PPC had higher levels of TNF-α (P < 0.05) in BAL from the nondependent lung before and after OLV than patients who did not have PPC. Patients who developed PPC had a smaller increase in MMP-2 levels (P < 0.05) in the dependent lung than patients who did not have PPC.
  
  
  CONCLUSIONS
  In lung resection surgery, the inflammatory response is similar in both lungs. However, the greater increase in TNF-α levels in the nondependent lung and the smaller increase of MMP-2 concentration in the dependent lung may increase the susceptibility to develop PPC.
authors.affiliation: From the Department of Anaesthesiology, Gregorio Marañón University General Hospital (FDLA, PP, IG, AR, LO, PC, PD, JC, PB), and Department of Biochemistry and Molecular Biology III, Medical Faculty, Complutense University of Madrid, Madrid, Spain (LR, EV).
authors.forename: Francisco
authors.initials: F
authors.lastname: de la Gala
authors.forename: Patricia
authors.initials: P
authors.lastname: Piñeiro
authors.forename: Ignacio
authors.initials: I
authors.lastname: Garutti
authors.forename: Almudena
authors.initials: A
authors.lastname: Reyes
authors.forename: Luis
authors.initials: L
authors.lastname: Olmedilla
authors.forename: Patricia
authors.initials: P
authors.lastname: Cruz
authors.forename: Patricia
authors.initials: P
authors.lastname: Duque
authors.forename: Javier
authors.initials: J
authors.lastname: Casanova
authors.forename: Lisa
authors.initials: L
authors.lastname: Rancan
authors.forename: Pilar
authors.initials: P
authors.lastname: Benito
authors.forename: Elena
authors.initials: E
authors.lastname: Vara
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D018836:Inflammation Mediators / Q000378:metabolism; D008168:Lung / Q000378:metabolism / Q000601:surgery; D011183:Postoperative Complications / Q000175:diagnosis / Q000378:metabolism; D011446:Prospective Studies; D011650:Pulmonary Alveoli / Q000378:metabolism
chemical_list: D018836:Inflammation Mediators