Correlation between changes in carotid Doppler and in cardiac output measurements
The linear correlation coefficient r between the percentage changes in CDPV and CI during EEOt was 0.52 [0.26–0.71]. A significant but lower correlation was found for cFT (On rmcorr, the percentage changes in CDPV vs. the percentage changes in CI were significantly correlated across EEOt and fluid challenge in responders (The clinical concordance plot showed that the overall fraction of concordant changes (CDPV or cFT vs. CI) was greater for cFT than for CDPV at EEOt (Additional file 