Prospective Evaluation of a Multibeat Analysis Cardiac Index Estimation in Patients With Cardiogenic Shock

• Published in: Journal of cardiothoracic and vascular anesthesia Vol. 37; no. 8; pp. 1377 - 1381
• Main Authors: Kee, Abigail, Kirchhoff, Brian, Grigsby, Joel, Proch, Katherine, Ji, Yoon, Agashe, Harshavardhan, Flynn, Brigid C.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.08.2023
• Subjects: arterial pulse contour; cardiac index; Cardiac Output; cardiogenic shock; Catheterization, Swan-Ganz; Coronary Artery Bypass; hemodynamic device; Humans; monitor; Reproducibility of Results; Shock, Cardiogenic - diagnosis; Shock, Cardiogenic - therapy; Thermodilution - methods; cardiac index; cardiogenic shock; monitor; hemodynamic device; arterial pulse contour
• ISSN: 1053-0770; 1532-8422; 1532-8422
• DOI: 10.1053/j.jvca.2023.04.003

The decision algorithm for managing patients in cardiogenic shock depends on cardiac index (CI) estimates. Cardiac index estimation via thermodilution (CI-TD) using a pulmonary artery catheter is used commonly for obtaining CI in these patients. Minimally invasive methods of estimating CI, such as multibeat analysis (CI-MBA), may be an alternative in this population. A prospective, observational study. Cardiac intensive care unit. Twenty-two subjects in cardiogenic shock provided 101 paired CI measurements. Measurements were obtained concomitantly by intermittent CI-TD and CI-MBA (Argos Cardiac Output Monitor; Retia Medical, Valhalla, NY). For each CI-TD, CI-MBA estimates were averaged over 1 minute to provide paired values. Bland-Altman and 4-quadrant analyses were performed by plotting changes between successive CI measurements (ΔCI) from each of the 2 methods. Concordance was calculated as a percentage using ΔCI data points from the 2 methods, outside an exclusion zone of 15%. The correlation coefficient between CI-MBA and CI-TD was 0.78 across patients. Mean CI-TD was 2.19 ± 0.46 L/min/m2 and mean CI-MBA was 2.38 ± 0.59 L/min/m2. The mean difference between CI-MBA and CI-TD (bias ± SD) was 0.20 ± 0.47 L/min/m2, and the limits of agreement were –0.72 to 1.11 L/min/m2. The percentage error was 40.0%. The concordance rate was 94%. A secondary analysis of a subgroup of patients during periods of arrhythmia demonstrated a similar accuracy of performance of CI-MBA. Cardiac index–MBA is not interchangeable with CI-TD. However, CI-MBA provides reasonable correlation and clinically acceptable trending ability compared with CI-TD. Cardiac output–MBA may be useful in trending changes in CI in patients with cardiogenic shock, especially in those whose pulmonary artery catheterization placement carries a high risk or is unobtainable.