Pulmonary artery vs. transpulmonary thermodilution for the assessment of cardiac output in mitral regurgitation: a prospective observational study
European Journal of Anaesthesiology, 08/10/2012
Staier K et al. – The results suggest that even severe mitral regurgitation has no significant impact on the accuracy of cardiac output (CO) measured by transpulmonary thermodilution (COTP). The precision of COTP was reduced under the condition of mitral regurgitation.Methods
- Thirty patients with mitral regurgitation undergoing elective mitral valve repair.
- COTP and COPAC were determined in triplicate after induction of anaesthesia, and at the end of surgery after closure of the chest.
- The methods were compared using bias and precision statistics.
- Echocardiography revealed severe mitral regurgitation in most patients (n=27) after induction of anaesthesia.
- The least significant change in COTP (the minimum change in COTP required to detect a real change with a probability of 95%) was increased under the condition of mitral regurgitation (15.4±10.2% after anaesthesia induction vs. 9.3±5.9% after valve repair, P=0.008), whereas it remained constant in COPAC (9.6±5.4 vs. 8.5±7.2%, P=0.55).
- There was no significant bias between COTP and COPAC after anaesthesia induction [mean CO, 4.03±0.92lmin-1; bias 0.12lmin-1 (95% confidence interval, CI,-0.073 to 0.311)], and after valve repair [mean CO 7.47±1.44lmin-1; bias 0.045lmin-1 (95% CI,-0.147 to 0.237)].
- The percentage error was 28.4 and 13.6%, respectively.