CARDIAC-OUTPUT MEASUREMENT IN CRITICALLY ILL PATIENTS - COMPARISON OFCONTINUOUS AND CONVENTIONAL THERMODILUTION TECHNIQUES

The purpose of the study was to compare cardiac output (GO) measuremen t by continuous (CTD) with that by conventional thermodilution (TD) in critically ill patients. In 19 of 20 critically ill patients requirin g a pulmonary artery catheterism, 105 paired CO measurements were perf ormed by both CTD and TD. Regression analysis showed that: CTD CO = 1. 18 TD CO - 0.42 Correlation coefficient was 0.96. Bias and limit of ag reement were - 0.8 and 2.4 L . min(-1), respectively. When a Bland and Altman diagram was constructed according to cardiac index ranges, bia ses were -0.2 and -0.3 and -0.8 L . min(-1) . m(-2) and limits of agre ement were 0.3, 0.7 and 1.6 L . min(-1) . m(-2) for low (<2.5 L . min( -1) . m(-2)), normal (between 2.5 and 4.5 L . min(-1) . m(-2)) and hig h (>45 L . min(-1) . m(-2)) cardiac indexes, respectively. It is concl uded that CTD, compared with TD, is a reliable method of measuring CO, especially when cardiac index is less than or equal to 4.5 L . min(-1 ) . m(-2).