Mechanisms in fluid retention - towards a mutual concept

Area of Science:

• Nephrology
• Cardiology
• Hepatology
• Obstetrics

Background:

• Fluid retention is a complex clinical challenge affecting multiple organ systems.
• Normal fluid homeostasis relies on balanced physiological mechanisms.
• Compromised fluid retention occurs in conditions like liver cirrhosis, heart failure, kidney failure, and preeclampsia.

Purpose of the Study:

• To review the similarities and differences in pathophysiological mechanisms of fluid retention.
• To identify shared elements like functional arterial underfilling across various conditions.
• To highlight knowledge gaps regarding the initiating factors of fluid retention.

Main Methods:

• Literature review focusing on fluid retention and homeostasis.
• Comparative analysis of pathophysiological mechanisms in different disease states.
• Identification of common and distinct features in water-retaining conditions.

Main Results:

• Functional arterial underfilling is a potential shared mechanism in cirrhosis, cardiac failure, cardiorenal/hepatorenal syndromes, and pregnancy.
• Distinct differences exist between these conditions, indicating varied underlying causes.
• The precise initiating factor (kidney dysfunction vs. arterial underfilling) remains unclear.

Conclusions:

• Understanding the interplay between kidney function and arterial underfilling is crucial for managing fluid retention.
• Further research is needed to elucidate the causal relationships in water-retaining states.
• Addressing knowledge gaps will improve clinical strategies for fluid retention.