If you wish to respond to a paper or other item already published in the BJA, please go to the abstract/full text version of that item and click on the link "E-Letters: Submit a response to the article".
Electronic Letters to:
|
|
E-letters: Electronic letters published:
-
![[Read E-letter]](/icons/misc/sectionDOWN.gif)
Evaluation of FloTrac/VigileoTM in patients undergoing liver transplantation
- Matthieu Biais, Karine Nouette-Gaulain, and François Sztark (22 December 2008)
|
|
|||
|
Matthieu Biais , Karine Nouette-Gaulain, and François Sztark
Send letter to journal:
|
Editor- We read with great interest the study by Biancofiore and colleagues comparing cardiac output obtained with pulmonary artery thermodilution (CO-PAC) and the uncalibrated pulse contour derived cardiac output (FloTrac/VigileoTM, CO-FloTrac) in patients undergoing liver transplantation (1). The authors showed (i) that the percentage error between the two methods was 54%, exceeding a 30% limit of acceptance, (ii) a log-linear relation between systemic vascular resistances (SVR) and the bias between both methods and (iii) that the CO-FloTrac was unable to track changes in cardiac index. While we agree with the main finding of this study, we would like to add some comments. These results are concordant with previously published data. We already compared CO-PAC and CO-FloTrac in 20 patients undergoing liver transplantation and found a percentage error of 43% and, most interestingly, a significant log-linear correlation between the SVR and the bias between the two methods (2). The impact of low SVR on CO-FloTrac determination is supported by the study published by Sakka and colleagues who found a percentage error of 35% between CO-FloTrac and CO obtained with transpulmonary thermodilution (CO-TPT) in septic patients with low SVR (3). A third generation of the FloTrac/VigileoTM system that is currently undergoing clinical validation has been designed to address the underestimation of cardiac output in patients with low SVR. Biancofiore and colleagues claim that the FloTrac/VigileoTM is unable to track changes in CO. In their study, the poor correlation between changes in CO-PAC and CO-FloTrac may be due to the substantial changes in SVR that occurred between two CO measurements, particularly in the peroperative period. Sakka and colleagues already found a poor correlation between changes in CO-TPT and CO-FloTrac after norepinephrine-induced changes in SVR (3). However, we recently showed that the FloTrac/VigileoTM is able to track changes in CO induced by fluid administration in the postoperative period of liver transplantation (4). SVR was unchanged before and after volume expansion perfomed over 20 minutes. Changes in CO-FloTrac correlated well with changes in CO-PAC (r²=0.77, P<0.0001). Cannesson and colleagues found similar results in patients undergoing cardiac surgery (5). In conclusion, we agree with the main finding of this study which confirms our previously published data. However, the authors should add that the FloTrac/VigileoTM can usually track changes in cardiac output except when large variations in SVR occur. Matthieu Biais* Karine Nouette-Gaulain François Sztark University Hospital of Bordeaux, France *Email : matthieu.biais@chu-bordeaux.fr 1 Biancofiore G, Critchley LA, Lee A, et al., Evaluation of an uncalibrated arterial pulse contour cardiac output monitoring system in cirrhotic patients undergoing liver surgery. Br J Anaesth 2009; 102: 47-54 2 Biais M, Nouette-Gaulain K, Cottenceau V, et al., Cardiac output measurement in patients undergoing liver transplantation: pulmonary artery catheter versus uncalibrated arterial pressure waveform analysis. Anesth Analg 2008; 106: 1480-6 3 Sakka SG, Kozieras J, Thuemer O and van Hout N, Measurement of cardiac output: a comparison between transpulmonary thermodilution and uncalibrated pulse contour analysis. Br J Anaesth 2007; 99: 337-42 4 Biais M, Nouette-Gaulain K, Cottenceau V, Revel P and Sztark F, Uncalibrated pulse contour-derived stroke volume variation predicts fluid responsiveness in mechanically ventilated patients undergoing liver transplantation. Br J Anaesth 2008; 101: 761-8 5 Cannesson M, Attof Y, Rosamel P, et al., Comparison of FloTrac cardiac output monitoring system in patients undergoing coronary artery bypass grafting with pulmonary artery cardiac output measurements. Eur J Anaesthesiol 2007; 24: 832-9 Conflict of Interest:None declared |
|||