Accuracy assessment of noninvasive cardiac output monitoring in the hemodynamic monitoring in critically ill patients

Abstract

Background: The consistency of cardiac output (CO) measured by noninvasive cardiac output monitoring (NICOM), pulse index continuous cardiac output (PiCCO), and ultrasound in the hemodynamic monitoring of critically ill patients was studied. Using the NICOM built-in passive leg raising (PLR) test, stroke volume index variation (ΔSVI) was calculated and was used to predict volume responsiveness in patients with circulatory shock (excluding cardiogenic shock). Methods: Critically ill patients requiring hemodynamic monitoring were admitted during the study period. The CO of each included patient under hemodynamic monitoring was measured by NICOM plus PiCCO or ultrasound, and the consistency of the measured COs was analyzed. By the NICOM built-in PLR test, ΔSVI was calculated and was used to predict volume responsiveness. Results: The CO of 58 patients was measured by NICOM and ultrasound, and the COs measured by these two methods were consistent. The CO of 40 patients was measured by NICOM and PiCCO, and the COs measured by these two methods were consistent. The volume responsiveness of all 98 patients was assessed by the NICOM built-in PLR test. A total of 60 patients had ΔSVI >10%, so they underwent the fluid challenge. Among them, 43 patients were positive by both the NICOM built-in PLR and fluid challenge. When using ΔSVI to predict volume responsiveness in patients with circulatory shock (excluding cardiogenic shock), the area under the receiver operating characteristic curve was 0.754 (95% confidence interval, 0.626-0.856), and the cut-off value was 18% (sensitivity: 88.37%, specificity: 52.94%), indicating that ΔSVI has value in predicting the volume responsiveness of patients with noncardiogenic circulatory shock. Conclusions: NICOM had good consistency with ultrasound and PiCCO in the hemodynamic monitoring of critically ill patients and can be for hemodynamic monitoring and evaluation in critically ill patients. The ΔSVI obtained by the NICOM built-in PLR test has certain clinical value in predicting the volume responsiveness of patients with circulatory shock (excluding cardiac shock) and provides a method for evaluating the volume responsiveness of critically ill patients.