Correlation of thermodilution-derived extravascular lung water and ventilation/perfusion-compartments in a porcine model

Purpose This study examines the correlation between the transpulmonary thermodilution derived extravascular lung water content (EVLW) and the ventilation/perfusion-distribution ( ) measured by multiple inert gas elimination (MIGET) in a porcine model. Methods measured by micropore membrane inlet mass spectrometry-MIGET (MMIMS-MIGET) and EVLW were simultaneously measured in twelve pigs in the heathy state, with impaired gas exchange from repetitive lung lavage and after 3 h of ventilation. The relationship between compartments and EVLW was analysed by linear correlation and regression. Results Considerable increases in EVLW and mismatching were induced through the lavage procedure. Significant correlations between the EVLW and the fractions representing pulmonary shunt and low were found. Perfusion to the normal regions was inversely correlated to the EVLW. Conclusions Increased EVLW is associated with increased low and shunt, but not equal to pulmonary shunt alone. Beneath true shunt EVLW can also be associated with low regions.