Esophageal Doppler and thermodilution are not interchangeable for determination of cardiac output

Abstract

Purpose: This study compares thermodilution cardiac output (TD-CO) and esophageal Doppler cardiac output (ED-CO) during periods of hemodynamic stability and after heart stabilization during off-pump coronary artery bypass (OPCAB) surgery. Methods:After Institutional Review Board approval, 58 patients undergoing OPCAB had simultaneous comparison of TD-CO and ED-CO at three time periods. Measurements were recorded, in a blinded manner, after probe insertion (T0), immediately before and after (T1,T2) heart displacement and before starting any pharmacological treatment (if needed) to maintain systolic blood pressure to its value before heart mobilization. Measurements were also taken before sternal closure (Tfinal).Results: Three hundred and two pairs of data were analyzed using the Bland and Altman method. Bias, standard deviation (SD) of the bias (precision), and degree of agreement (bias ± 2 SD) were calculated. Based on published literature, we considered that the highest degree of agreement should be < 0.5 L·min -1 to consider both methods as interchangeable. At T0, bias and SD of bias between TD-CO and ED-CO were -0.1 ± 1.0 L·min -1 . Immediately before heart stabilization, bias ± SD was 0.6 ± 1.0 L·min -1 and after heart displacement, 0.5 ± 0.8 L·min Conclusion:Because the degree of agreement was > 0.5 L·min -1 at all measurement periods except T0, we conclude that TD and ED are not interchangeable at any time during OPCAB surgery. Objectif : Comparer le débit cardiaque obtenu par thermodilution (DC-TD) à celui du Doppler oesophagien (DC-DO) pendant la stabilité hémodynamique et après la stabilisation cardiaque au cours d'un pontage aortocoronarien à coeur battant (PACCB). Méthode : Avec l'approbation du Comité de révision, nous avons recruté 58 patients devant subir un PACCB pour une comparaison simultanée du DC-TD et DC-DO à trois moments différents. Les mesures ont été enregistrées à l'aveugle, après l'insertion de la sonde (T0), immédiatement avant et après (T1,T2) le déplacement

Reply to Letter: Agreed: “PRAM May be Useful to Assess the Cardiovascular Changes in Obese Patients During Laparoscopy”

“…Indeed, using TEE and transesophageal echo-Doppler techniques, values similar to those obtained by PRAM are reported [7,8]. Unfortunately, however, intracardiac volumes using TEE and SV determined by the echoDoppler-velocimetry method underestimate by 20-30% SV obtained by magnetic resonance imaging, cineventriculography, and TDCO [11][12][13][14][15][16]. With respect to CI/CO determination by means of ICG in the morbidly obese patient during ppn, Aloni et al [9] reported values essentially equivalent to the TDCO studies of Nguyen et al and Artuso et al Review of the literature, however, shows that ICG systematically underestimates TDCO/ TDCI in the morbidly obese and critically ill patient by 15-20% [17,18].…”

The Accuracy and Reliability of Cardiac Output Assessment by Measuring Descending Aortic Blood Flow in Patients Undergoing Cardiac Surgery

“…Previous studies found that hypovolemia and severe hypotension could reduce the blood ow of renal and gastrointestinal to change the distribution of blood ow between upper and lower body [12,13]. Low CO, which was fairly common during off-pump coronary artery bypass graft, leaded to the upper body blood ow probably higher than 30% of CO [13].…”

Minimally Invasive Monitoring of Cardiac Output in the Cardiac Surgery Intensive Care Unit

“…However, these studies generally were performed in patients under stable hemodynamic conditions. In contrast, esophageal Doppler had poor agreement with PAC in patients undergoing off-pump coronary artery bypass surgery [19,20]. Based on these inherent limitations of esophageal Doppler devices, their utility appears to be limited to patients in the cardiac surgery population who are hemodynamically stable and in the presence of skilled operators.…”