The pathogenesis and treatment of lung oedema in critical illness

Experiments were performed at the Waikato Institute of Technology (Wintec) using an isolated perfused rat lung preparation. The first set of experiments examined the influence of administration of mesenteric lymph from donor animals induced with acute pancreatitis or sepsis on respiratory function. Consistent evidence of respiratory deterioration was not able to be demonstrated. The second component of the project investigated whether deterioration in lung function could be slowed or prevented by pharmacological treatments acting to reduce the development of inflammation in response to over-inflation of lung tissue. A model of lung deterioration was developed in which lung function deteriorated during a 1-hour period of hyperinflation using higher-than-normal positive pressure ventilation. Lung inflammation, as assessed by oedemic weight gain, was reduced by administration of pharmacological agents- Drug A and Drug B. Animals treated with Drug A also had higher tidal volume over the first 40 min after cessation of hyperinflation demonstrating that there was less damage in these lungs. These exciting results have provided a foundation for ongoing testing of drugs with a view to eventual clinical treatment for a range of conditions that cause airway inflammation