Abstract: SA-PO1026
Beyond Ultrafiltration: Thoracic Fluid Content Index and Intradialytic Blood Pressure Trends in Hemodialysis
Session Information
- Hemodialysis: Risk Factors, Epidemiology, and Outcomes
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Dialysis
- 801 Dialysis: Hemodialysis and Frequent Dialysis
Authors
- Jumani, Muhammed Yaseen, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
- Van Buren, Peter N., The University of Texas Southwestern Medical Center, Dallas, Texas, United States
Background
Bioimpedance spectroscopy (BIS) can assess volume status in hemodialysis (HD), but use is limited by implanted cardiac devices, implanted hardware, and amputations.. Thoracic fluid content index (TFCI), measured by impedance cardiography, may provide an alternative marker. We examined associations between TFCI, BIS-derived volume metrics, and intradialytic blood pressure (BP) trends.
Methods
We retrospectively analyzed 75 HD patients with pre- and post-midweek HD BIS and impedance cardiography. Pearson correlation compared pre/post-HD TFCI with total body water (TBW), extracellular water (ECW), intracellular water (ICW), ECW/TBW, ECW/weight, and calculated fluid overload (FO) [1.136(ECW)-0.43(ICW)-0.114(weight)]. Multivariable linear regression tested whether percent reduction in TFCI predicted intradialytic BP slope, adjusting for age, sex, race, diabetes, and percent body weight removed with ultrafiltration.
Results
Mean age was 49.4±12 years; 61% were men, 60% Black, and 59% had diabetes. Mean pre/post-HD TFCI were 21.9±6.8 and 20.7±7.0 (kΩ)-1*m-2. TFCI did not significantly correlate with absolute TBW, ECW, ICW, or ECW/TBW. TFCI correlated strongly with ECW/weight and moderately with FO (Table). In adjusted regression, greater percent reduction in TFCI was independently associated with more negative intradialytic BP slope (standardized β=-0.3, p=.03).
Conclusion
TFCI correlated with BIS-derived relative volume overload markers, particularly ECW/weight and calculated FO, but not absolute body water compartments. Greater reductions in TFCI during HD were associated with steeper intradialytic BP declines. TFCI may serve as an adjunctive marker for volume assessment and dry weight management when BIS is unavailable or limited.
Correlation of Thoracic Fluid Content Index With Bioimpedance-Derived Volume Overload Metrics
| Bioimpedance metric | Pre-HD TFCI | Post-HD TFCI |
| Pre-HD ECW/weight Post-HD ECW/weight | 0.7 (<.0001) 0.7 (<.0001) | 0.6 (<.0001) 0.7 (<.0001) |
| Pre-HD fluid overload Post-HD fluid overload | 0.4 (.0001) 0.4 (.0002) | 0.4 (.0004) 0.5 (<.0001) |