Cardiac index assessment using bioreactance in patients undergoing cytoreductive surgery in ovarian carcinoma

This clinical study compared the cardiac index (CI) assessed by the totally non-invasive method of bioreactance (CI_BR) (NICOM?, Cheetah Medical, Vancouver, USA) to transpulmonary thermodilution (CI_TD) during cytoreductive surgery in ovarian carcinoma. The hypothesis was that CI could be assessed by bioreactance in an accurate and precise manner including accurate trending ability when compared to transpulmonary thermodilution. In 15 patients CI_BR and CI_TD were assessed after induction of anesthesia, after opening of the peritoneum, hourly during the operative procedure, and 30 min after extubation. Trending ability was assessed between the described timepoints. In total 84 points of measurement were analyzed. Concordance correlation coefficient for repeated measures correlating the CI_BR and CI_TD was 0.32. Bias was 0.26 l/min/m² (limits of agreement ?1.39 and 1.92 l/min/m²). The percentage error was 50.7 %. Trending ability quantified by the mean of angles θ which are made by the ΔCI vector and the line of identity (y = x) showed a value for CI_BR of θ = 23.4°. CI assessment by bioreactance showed acceptable accuracy and trending ability. However, its precision was poor. Therefore, CI measurement can not be solely based on bioreactance in patients undergoing cytoreductive surgery in ovarian carcinoma.