Sepsis is one of the systemic inflammatory responses, and it can cause acute respiratory distress syndrome (ARDS). Mechanical ventilation (MV) is one of the best treatments in patients with sepsis related to ARDS. However, mechanical ventilation itself can cause lung injury through various mechanisms. In this study, we applied mouse cecal ligation and puncture (CLP) model of sepsis with subsequent injurious ventilation to determine if sepsis could affect the development of ventilator-induced lung injury (VILI). To evaluate lung injury caused by sepsis, mild, moderate, and severe CLPs were induced. To evaluate lung injury caused by MV with or without sepsis, tidal volume (7 mL/kg, 10 mL/kg, or 24 mL/kg) was maintained for 3 h with or without septic insult (mild sepsis for 72 h). Lung compliance was then determined and biochemical evaluations were performed. Results showed that lung compliance was lower in the severe sepsis group compared to that in the mild or moderate sepsis group. MV alone decreased lung compliance in a tidal volume dependent manner. Both CLP and VILI groups showed significant decrease in lung compliance and increase in total cell count upon bronchoalveolar lavage fluid. These results confirm that ventilation can affect lung injury in mouse sepsis model.

Introduction
Materials and Methods
    Animal preparation
    Cecal ligation and puncture (CLP)
    Ventilation condition
    Lung function test
    Bronchoalveolar lavage (BAL) analysis
    Statistical analysis
Results
    CLP induces lung injury
    Ventilation induces lung injury
    CLP accelerates VILI
Discussion
References

• Sookhan Jung(Division of Animal Diseases and Health, National Institute of Animal Science, Rural Development Administration)
• Suhee Kim(Division of Animal Diseases and Health, National Institute of Animal Science, Rural Development Administration)
• Hwajin Cho(Department of Pediatrics, Chonnam National University Children's Hospital and Medical School)
• Inseok Jeong(Department of Thoracic and Cardiovascular Surgery, Chonnam National University Hospital)
• Jinho Park(College of Veterinary Medicine, Chonbuk National University)
• Dong-In Jung(Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University)
• DoHyeon Yu(Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University) Corresponding author