Prognostic Value of Electrical Cardiometry–Derived Thoracic Fluid Content in Respiratory Intensive Care Unit Patients: A Prospective Observational Study

Background : Hemodynamic instability is common among respiratory intensive care unit (RICU) patients and is associated with multi-organ dysfunction and high mortality. 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 showed significantly higher mean TFC values on 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 mechanical ventilation and vasopressor use (p < 0.001). 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. Routine TFC monitoring may assist in early detection of fluid overload and guide individualized fluid management. Trial registration : ClinicalTrials.gov identifier: NCT07100821