title: Incidence of mortality and morbidity related to postoperative lung injury in patients who have undergone abdominal or thoracic surgery: a systematic review and meta-analysis.
abstract: BACKGROUND
  Lung injury is a serious complication of surgery. We did a systematic review and meta-analysis to assess whether incidence, morbidity, and in-hospital mortality associated with postoperative lung injury are affected by type of surgery and whether outcomes are dependent on type of ventilation.
  
  
  METHODS
  We searched MEDLINE, CINAHL, Web of Science, and Cochrane Central Register of Controlled Trials for observational studies and randomised controlled trials published up to April, 2014, comparing lung-protective mechanical ventilation with conventional mechanical ventilation during abdominal or thoracic surgery in adults. Individual patients' data were assessed. Attributable mortality was calculated by subtracting the in-hospital mortality of patients without postoperative lung injury from that of patients with postoperative lung injury.
  
  
  RESULTS
  We identified 12 investigations involving 3365 patients. The total incidence of postoperative lung injury was similar for abdominal and thoracic surgery (3·4% vs 4·3%, p=0·198). Patients who developed postoperative lung injury were older, had higher American Society of Anesthesiology scores and prevalence of sepsis or pneumonia, more frequently had received blood transfusions during surgery, and received ventilation with higher tidal volumes, lower positive end-expiratory pressure levels, or both, than patients who did not. Patients with postoperative lung injury spent longer in intensive care (8·0 [SD 12·4] vs 1·1 [3·7] days, p<0·0001) and hospital (20·9 [18·1] vs 14·7 [14·3] days, p<0·0001) and had higher in-hospital mortality (20·3% vs 1·4% p<0·0001) than those without injury. Overall attributable mortality for postoperative lung injury was 19% (95% CI 18-19), and differed significantly between abdominal and thoracic surgery patients (12·2%, 95% CI 12·0-12·6 vs 26·5%, 26·2-27·0, p=0·0008). The risk of in-hospital mortality was independent of ventilation strategy (adjusted HR 0·71, 95% CI 0·41-1·22).
  
  
  CONCLUSIONS
  Postoperative lung injury is associated with increases in in-hospital mortality and durations of stay in intensive care and hospital. Attributable mortality due to postoperative lung injury is higher after thoracic surgery than after abdominal surgery. Lung-protective mechanical ventilation strategies reduce incidence of postoperative lung injury but does not improve mortality.
  
  
  BACKGROUND
  None.
authors.affiliation: Department of Intensive Care, Academic Medical Centre, University of Amsterdam, Amsterdam, Netherlands; Medical Intensive Care Unit, ABC Medical School (FMABC), Santo André, Brazil; Department of Critical Care Medicine, Hospital Israelita Albert Einstein, São Paulo, Brazil. Electronic address: aryserpa@terra.com.br.
authors.forename: Ary
authors.initials: A
authors.lastname: Serpa Neto
authors.affiliation: Department of Intensive Care, Academic Medical Centre, University of Amsterdam, Amsterdam, Netherlands; Department of Anaesthesiology, Academic Medical Centre, University of Amsterdam, Amsterdam, Netherlands.
authors.forename: Sabrine N T
authors.initials: SN
authors.lastname: Hemmes
authors.affiliation: Department of Critical Care Medicine, Hospital Israelita Albert Einstein, São Paulo, Brazil.
authors.forename: Carmen S V
authors.initials: CS
authors.lastname: Barbas
authors.affiliation: Department of Anaesthesiology, Düsseldorf University Hospital, Heinrich-Heine University, Düsseldorf, Germany; Department of Anaesthesiology, Marienhospital Osnabrück, Osnabrück, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Beiderlinden
authors.affiliation: Department of Anesthesiology, University of Colorado, Aurora, CO, USA.
authors.forename: Ana
authors.initials: A
authors.lastname: Fernandez-Bustamante
authors.affiliation: Department of Aneasthesiology and Critical Care Medicine, Estaing University Hospital, Clermont-Ferrand, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Futier
authors.affiliation: Department of Intensive Care, Academic Medical Centre, University of Amsterdam, Amsterdam, Netherlands.
authors.forename: Markus W
authors.initials: MW
authors.lastname: Hollmann
authors.affiliation: Department of Critical Care Medicine and Anaesthesiology (SAR B), Saint Eloi University Hospital, Montpellier, France.
authors.forename: Samir
authors.initials: S
authors.lastname: Jaber
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Alf
authors.initials: A
authors.lastname: Kozian
authors.affiliation: Department of Anaesthesiology, Pharmacology and Intensive Care, Faculty of Medicine, University Hospital of Geneva, Geneva, Switzerland.
authors.forename: Marc
authors.initials: M
authors.lastname: Licker
authors.affiliation: State Key Laboratory of Oncology of South China, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, China.
authors.forename: Wen-Qian
authors.initials: WQ
authors.lastname: Lin
authors.affiliation: Department of Anesthesiology, University of Colorado, Aurora, CO, USA.
authors.forename: Pierre
authors.initials: P
authors.lastname: Moine
authors.affiliation: Department of Anesthesiology and Anesthesia Clinical Research Unit, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Federica
authors.initials: F
authors.lastname: Scavonetto
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Schilling
authors.affiliation: Department of Anaesthesia, Azienda Ospedaliera Fondazione Macchi, Ospedale di Circolo, Varese, Italy.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Selmo
authors.affiliation: Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Severgnini
authors.affiliation: Department of Anesthesiology and Anesthesia Clinical Research Unit, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Juraj
authors.initials: J
authors.lastname: Sprung
authors.affiliation: Department of Anaesthesiology, Düsseldorf University Hospital, Heinrich-Heine University, Düsseldorf, Germany.
authors.forename: Tanja
authors.initials: T
authors.lastname: Treschan
authors.affiliation: Department of Anaesthesiology, Hospital de Sant Pau, Barcelona, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Unzueta
authors.affiliation: Department of Anesthesiology and Anesthesia Clinical Research Unit, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, USA.
authors.forename: Toby N
authors.initials: TN
authors.lastname: Weingarten
authors.affiliation: Department of Intensive Care, Academic Medical Centre, University of Amsterdam, Amsterdam, Netherlands.
authors.forename: Esther K
authors.initials: EK
authors.lastname: Wolthuis
authors.affiliation: Department Anaesthesiology and Intensive Care Medicine, University of Leipzig, Leipzig, Germany.
authors.forename: Hermann
authors.initials: H
authors.lastname: Wrigge
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, University Hospital Carl Gustav Carus, Dresden, Germany.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Gama de Abreu
authors.affiliation: Department of Surgical Sciences and Integrated Diagnostics, IRCCS San Martino IST, University of Genoa, Genoa, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Pelosi
authors.affiliation: Department of Intensive Care, Academic Medical Centre, University of Amsterdam, Amsterdam, Netherlands; Department of Anaesthesiology, Academic Medical Centre, University of Amsterdam, Amsterdam, Netherlands; Laboratory of Experimental Intensive Care and Anaesthesiology, Academic Medical Centre, University of Amsterdam, Amsterdam, Netherlands.
authors.forename: Marcus J
authors.initials: MJ
authors.lastname: Schultz
mesh_terms: D000005:Abdomen / Q000601:surgery*; D000368:Aged; D005260:Female; D006801:Humans; D007902:Length of Stay; D055370:Lung Injury / Q000209:etiology / Q000401:mortality* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration / Q000401:mortality; D011183:Postoperative Complications / Q000209:etiology / Q000401:mortality; D016032:Randomized Controlled Trials as Topic; D019616:Thoracic Surgical Procedures / Q000009:adverse effects* / Q000401:mortality