Name
Abstract | ||
|---|---|---|
The study's goal was to determine if cardiac output (CO), obtained by impedance cardiography (ICG), would be improved by a new equation N, implementing a square root transformation for dZ/dt(max)/Z(0), and a variable magnitude, mass-based volume conductor V-C. Pulmonary artery catheterisation was performed on 106 cardiac surgery patients pre-operatively. Post-operatively, thermodilution cardiac output (TDCO) was simultaneously compared with ICG CO. dZ/dt(max)/Z(0) and Z(0) were obtained from a proprietary bioimpedance device. The impedance variables, in addition to left ventricular ejection time T-LVE and patient height and weight, were input using four stroke volume (SW equations: Kubicek (K), Sramek (S), Sramek- Bernstein (SB), and a new equation N. CO was calculated as SV x heart rate. Data are presented as mean +/- SD. One way repeated measures of ANOVA followed by the Tukey test were used for inter-group comparisons. Bland-Altman methods were used to assess bias, precision and limits of agreement. P < 0.05 was considered statistically significant. CO implementing N (6.06 +/- 1.48 l min(-1)) was not different from TDCO (5.97 +/- 1.41 l min(-1)). By contrast, CO calculated using K (3.70 +/- 1.53 l min(-1)), S (4.16 +/- 1.83 l min(-1)) and SB (4.37 +/- 1.82 l min(-1)) was significantly less than TDCO. Bland-Altman analysis showed poor agreement between TDCO and K, S and SB, but not between TDCO and N. Compared with TDCO, equation N, using a square-root transformation for dZ/dt(max)/Z(0), and a mass-based V-C, was superior to existing transthoracic impedance techniques for SV and CO determination. |
Year | DOI | Venue |
|---|---|---|
2005 | 10.1007/BF02344724 | MEDICAL & BIOLOGICAL ENGINEERING & COMPUTING |
Keywords | DocType | Volume |
stroke volume, cardiac output, impedance cardiography, acceleration, dZ/dt(max) | Journal | 43 |
Issue | ISSN | Citations |
4 | 0140-0118 | 12 |
PageRank | References | Authors |
2.04 | 0 | 2 |
Name | Order | Citations | PageRank |
|---|---|---|---|
| D. P. Bernstein | 1 | 12 | 2.04 |
| H. J. M. Lemmens | 2 | 12 | 2.04 |