Prognostic value of electrical cardiometry–derived thoracic fluid content in respiratory intensive care unit patients: a prospective observational study

Abstract

Background
Electrical cardiometry (EC) is a noninvasive method that continuously measures thoracic fluid content (TFC), providing real-time assessment of fluid status. This study evaluated the prognostic value of EC-derived TFC in predicting outcomes among critically ill respiratory patients.


Methods
A prospective observational study was conducted on 130 adult patients admitted to the RICU of Mansoura University Hospitals. Daily hemodynamic measurements were obtained using the ICON™ noninvasive cardiometer. Primary outcomes included duration of invasive mechanical ventilation (MV) and RICU stay, while in-hospital mortality was the secondary endpoint. Correlations between TFC and clinical, hemodynamic, and biochemical parameters were analyzed.


Results

Pneumonia was the most frequent diagnosis (65.4%), followed by COPD (15.4%). Non-survivors had significantly higher mean TFC values across all follow-up days compared with survivors (
p
 < 0.001). TFC correlated positively with RICU stay and serum lactate levels and negatively with mean arterial pressure. At a cutoff value of 43 kΩ⁻¹, TFC predicted mortality with an AUC of 0.656, sensitivity of 85.7%, and specificity of 67.3%. Elevated TFC values were also significantly associated with the need for mechanical ventilation and vasopressor use (
p
 < 0.001). At a cutoff value of 43 kΩ⁻¹, TFC predicted in-hospital mortality with a sensitivity of 85.7%, specificity of 67.3%, and an area under the curve (AUC) of 0.656.



Conclusion
Electrical cardiometry provides a reliable, noninvasive technique for continuous hemodynamic monitoring in respiratory critical care. Elevated TFC values were independently associated with higher mortality, prolonged mechanical ventilation, and extended RICU stay.


Trial registration
ClinicalTrials.gov identifier NCT07100821.