LUNG BACTERIAL CLEARANCE FOLLOWING PULMONARY CONTUSION

  • 1 January 1979
    • journal article
    • research article
    • Vol. 86  (5) , 730-735
Abstract
Bacterial infections frequently complicate pulmonary contusion and are the leading cause of death in such patients. This study evaluated effects of pulmonary contusion alone and contusion associated with other factors on the ability to clear aerosolized bacteria from the lung. Lung bacterial clearance of Staphylococcus aureus and Klebsiella pneumoniae was studied in animals with isolated pulmonary contusion or contusion associated with blood loss, rapid crystalloid infusion or steroid administration. An isolated pulmonary contusion produced no impairment of the ability of the contused lung to clear gram-negative or gram-positive organisms. Addition of acute blood loss and crystalloid infusion resulted in decreased clearance from the contused lung; steroid administration caused marked depression in lung bacterial clearance from the non-injured lung. The canine model described allowed for study of regional differences in bacterial clearance. The contused lung is not more susceptible to bacterial infection than the normal lung. Acute blood loss renders the contused lung less able to clear bacteria. Crystalloid infusion markedly depresses lung bacterial clearance. Steroids have a deleterious anti-bacterial effect on contused and non-contused lungs.