title: Effect of hypertonic saline treatment on the inflammatory response after hydrochloric acid-induced lung injury in pigs.
abstract: OBJECTIVE
  Hypertonic saline has been proposed to modulate the inflammatory cascade in certain experimental conditions, including pulmonary inflammation caused by inhaled gastric contents. The present study aimed to assess the potential anti-inflammatory effects of administering a single intravenous dose of 7.5% hypertonic saline in an experimental model of acute lung injury induced by hydrochloric acid.
  
  
  METHODS
  Thirty-two pigs were anesthetized and randomly allocated into the following four groups: Sham, which received anesthesia and were observed; HS, which received intravenous 7.5% hypertonic saline solution (4 ml/kg); acute lung injury, which were subjected to acute lung injury with intratracheal hydrochloric acid; and acute lung injury + hypertonic saline, which were subjected to acute lung injury with hydrochloric acid and treated with hypertonic saline. Hemodynamic and ventilatory parameters were recorded over four hours. Subsequently, bronchoalveolar lavage samples were collected at the end of the observation period to measure cytokine levels using an oxidative burst analysis, and lung tissue was collected for a histological analysis.
  
  
  RESULTS
  Hydrochloric acid instillation caused marked changes in respiratory mechanics as well as blood gas and lung parenchyma parameters. Despite the absence of a significant difference between the acute lung injury and acute lung injury + hypertonic saline groups, the acute lung injury animals presented higher neutrophil and tumor necrosis factor alpha (TNF-α), interleukin (IL)-6 and IL-8 levels in the bronchoalveolar lavage analysis. The histopathological analysis revealed pulmonary edema, congestion and alveolar collapse in both groups; however, the differences between groups were not significant. Despite the lower cytokine and neutrophil levels observed in the acute lung injury + hypertonic saline group, significant differences were not observed among the treated and non-treated groups.
  
  
  CONCLUSIONS
  Hypertonic saline infusion after intratracheal hydrochloric acid instillation does not have an effect on inflammatory biomarkers or respiratory gas exchange.
authors.affiliation: Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Carla Augusto
authors.initials: CA
authors.lastname: Holms
authors.affiliation: Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Denise Aya
authors.initials: DA
authors.lastname: Otsuki
authors.affiliation: Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Marcia
authors.initials: M
authors.lastname: Kahvegian
authors.affiliation: Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Cristina Oliveira
authors.initials: CO
authors.lastname: Massoco
authors.affiliation: Department of Surgery, São Paulo, SP, Brazil.
authors.forename: Denise Tabacchi
authors.initials: DT
authors.lastname: Fantoni
authors.affiliation: Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Paulo Sampaio
authors.initials: PS
authors.lastname: Gutierrez
authors.affiliation: Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Jose Otavio Costa
authors.initials: JO
authors.lastname: Auler Junior
mesh_terms: D055371:Acute Lung Injury / Q000188:drug therapy* / Q000473:pathology; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001772:Blood Cell Count; D016207:Cytokines / Q000032:analysis / Q000187:drug effects; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006851:Hydrochloric Acid; D009504:Neutrophils / Q000187:drug effects; D011897:Random Allocation; D015203:Reproducibility of Results; D012462:Saline Solution, Hypertonic / Q000494:pharmacology / Q000627:therapeutic use*; D013552:Swine; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000893:Anti-Inflammatory Agents; D016207:Cytokines; D012462:Saline Solution, Hypertonic; D006851:Hydrochloric Acid