[Determination of extravascular lung water in critical patients: comparison with radiological, hemodynamic and...

Measurement of extravascular lung water (EVLW) was performed by the thermal-dye technique in 55 critically ill patients. The EVLW values were compared with the corresponding radiographic, hemodynamic and functional pulmonary data. EVLW values revealed a positive correlation with the chest X-ray score (CXR) (r = 0.836; p less than 0.001), mean pulmonary artery pressure (PP) (r = 0.414; p less than 0.01), pulmonary capillary wedge pressure (PCWP) (r = 0.353; p less than 0.01), venous admixture (Qs/Qt) (r = 0.288; p less than 0.05), and alveo-arterial oxygen difference/fraction of inspired oxygen (AaDO2/FiO2) (r = 0.441; p less than 0.001). No correlation was found between EVLW values and colloid-osmotic pressure minus PCWP (COP-PCWP) (r = 0.221). Though different positive correlations between EVLW values and these parameters were found, they cannot replace EVLW measurement. Rather, EVLW measurement provides additional information on the degree of pulmonary edema which is useful in differentiating between cardiac and non-cardiac pulmonary edema and in states of radiologic over- or underestimation of EVLW.