Validation of cardiac output estimation using the fourth-generation FloTrac/EV1000™ system in patients undergoing robotic-assisted off-pump coronary artery bypass surgery

• Published in: Heart and vessels Vol. 38; no. 3; pp. 341 - 347
• Main Authors: Wu, Nien-Hsun, Hsieh, Tsung-Han, Chang, Chun-Yu, Shih, Ping-Chen, Kao, Ming‐Chang, Lin, Han-Yu
• Format: Journal Article
• Language: English
• Published: Tokyo Springer Japan 01.03.2023; Springer Nature B.V
• Subjects: Algorithms; Anesthesia; Bias; Biomedical Engineering and Bioengineering; Blood pressure; Calibration; Cardiac Output; Cardiac Surgery; Cardiology; Coronary artery; Coronary Artery Bypass, Off-Pump - adverse effects; Coronary vessels; Error analysis; External pressure; Heart; Heart surgery; Hemodynamics; Humans; Invasiveness; Medical instruments; Medicine; Medicine & Public Health; Monitoring, Intraoperative - methods; Original Article; Ostomy; Pulmonary arteries; Pulmonary artery; Pulmonary Artery - surgery; Regression analysis; Reliability analysis; Reproducibility of Results; Robotic Surgical Procedures - adverse effects; Robotics; Software reliability; Surgery; Thermodilution - methods; Upgrading; Vascular Surgery; Veins & arteries; Waveforms; Thermodilution; Cardiac output; Arterial pressure waveform analysis; Off-pump coronary artery bypass; Robotic-assisted cardiac surgery
• ISSN: 0910-8327; 1615-2573
• DOI: 10.1007/s00380-022-02177-x

The pulmonary artery catheter (PAC)—despite its invasiveness—remains the gold standard for cardiac output (CO) monitoring. The FloTrac system, a less invasive hemodynamic monitor has been developed, which estimates CO using arterial pressure waveform analysis without external calibration. Recently, an upgraded version of FloTrac system with improved algorithm to follow changes in vascular resistance was introduced into the market. The aim of this study was to assess the reliability of the CO estimated from the fourth-generation FloTrac/EV1000 system (CO FT ) compared to that measured with PAC using the thermodilution method (CO PAC ) during robotic-assisted off-pump coronary artery bypass (OPCAB) surgery. CO FT and CO PAC were obtained simultaneously at 4 predefined time points during robotic-assisted OPCAB: 5 min after the induction of general anesthesia (T1), after starting one-lung ventilation (T2), after capnothorax (T3), and after mini-thoracotomy was performed (T4). The agreement of data was investigated by Bland–Altman analysis. Thirty-four patients were initially enrolled. After exclusion, 32 patients and a total of 128 paired CO measurements were obtained. The overall bias was 1.46 L/min, the 95% limits of agreements were − 3.40 to 6.33 L/min, and the percentage error was 72.98%. Regression analysis of the systemic vascular resistance index (SVRI) and the bias between CO PAC and CO FT showed that the bias was moderately correlated with the SVRI ( r 2  = 0.43; p  < 0.0001). Despite a software upgrade, the reliability of the fourth-generation FloTrac/EV1000™ system during robotic-assisted OPCAB to estimate CO was not acceptable, especially in patients with low SVRI.