Сardiac index and stroke volume variation estimated by the pulse wave transit time analysis in comparison with variables derived by pulse contour analysis after coronary revascularization on a beating heart

Abstract

The objective was to validate cardiac index (CI) and stroke volume variation (SVV) measured by pulse wave transit time (PWTT) technology  using estimated continuous cardiac output (esCCO) technique, with pulse contour analysis (PCA) after off-pump coronary artery bypass grafting  (OPCAB)Materials and methods. The study involved 21 patients after elective OPCAB. In all patients, CI and SVV were measured with both esCCO technique  (CIesCCO and esSVV) and PCA (CIPCA and SVVPCA). The agreement between methods was analyzed using correlation analysis and Bland-Altman  analysis. In addition, the trending ability of esCCO technique to control changes in CI during dynamic tests was investigated.  Results. During the study, 178 pairs for CI and 174 pairs for SVV were collected. The mean bias between CIesCCO and CIPCA was 0.06 L·min–1 m–2 with limits of agreement of ± 0.92 L·min–1 m–2 and a percentage error of 35.3%. The concordance rate of CIesCCO was 70%. The mean bias between  esSVV and SVVPCA achieved – 6.1% with limits of agreement of ± 15.5% and percentage error of 137%.Conclusions. The coherence of CIesCCO and esSVV based on PWTT in comparison with PCA is not appropriate. Further development of this  monitoring algorithm may be required for more correct measurement of cardiac output and fluid responsiveness