Impact of Fluid Management on Outcomes in Sequential Extracorporeal Support: A Post Hoc Analysis

Abstract

Introduction: Sepsis is a life-threatening condition characterized by dysregulated inflammatory responses, often leading to multiple organ dysfunction and high mortality rates. Continuous renal replacement therapy (CRRT) and extracorporeal blood purification therapies have emerged as vital adjuncts to manage fluid overload and modulate immune responses in septic shock. This study evaluates the impact of daily fluid balance variation on 90-day mortality and hospital length of stay in ICU patients undergoing CRRT for septic shock with endotoxin activity.

Methods: A post hoc analysis of the EUPHAS 2 project was conducted on 61 ICU patients with nonresponsive endotoxin shock at San Bortolo Hospital (2016-2021). Bayesian joint models assessed the relationship between fluid balance and mortality. Mediation analysis explored the impact of CRRT on mechanical ventilation duration and hospital stay.

Results: Fluid overload and excessive ultrafiltration were associated with prolonged mechanical ventilation and extended hospital stays. Targeted fluid balance management reduced 90-day mortality risk by 50%. CRRT reduced hospital length of stay directly by 5.31 days but indirectly extended it by 11.78 days due to mechanical ventilation. Optimal fluid balance was critical for minimizing mortality and complications.

Conclusions: Careful and tailored fluid management in CRRT is essential for improving survival rates and clinical outcomes in septic shock patients. Continuous monitoring of fluid dynamics is necessary to optimize hemodynamic stability and avoid complications. Future multicenter studies are needed to validate these findings and refine fluid management protocols.

Keywords: Continuous renal replacement therapy; Extracorporeal blood purification; Fluid balance; Hemodynamic stability; Septic shock; Ultrafiltration.