[Correlation between slopes of pulmonary blood flow-driving pressure curve and routine pulmonary function]

In 91 preoperative cases of lung cancer, an attempt was made to correlate the slopes of pulmonary blood flow-driving pressure curve (delta DP/delta CI), as constructed from unilateral pulmonary arterial occlusion (UPAO) test values and pulmonary blood flow fraction values as measured by scintigraphy, with total pulmonary vascular resistance index (TPVRI) and pulmonary vascular resistance index (PVRI) and routine pulmonary function. FVC and FEV per unit body surface (BSA) were found to correlate, to same degree, with delta DP/delta CI, TPVRI and PVRI (p less than 0.05). delta DP/delta CI correlated significantly with FRC/BSA, whereas TPVRI and PVRI did not. 3) The inverse of the cardiac index (1/cardiac index) was shown to significantly correlate with TPVRI and PVRI (r = 0.64, 0.48), but poorly with delta DP/delta CI (r = 0.32). These results suggest that delta DP/delta CI might possibly provide a more useful quantitative index for the pulmonary vascular bed than TPVRI and PVRI.