Thermal balance in convective therapies

Area of Science:

• Nephrology
• Cardiovascular Physiology
• Biomedical Engineering

Background:

• Intradialytic hemodynamic instability is a significant concern during dialysis.
• Dialysate temperature and convective therapies like hemofiltration (HF) are implicated in cardiovascular response.
• The role of thermal balance in dialysis-induced hemodynamic stability is debated.

Purpose of the Study:

• To compare the thermal balance and hemodynamic effects of conventional hemodialysis (HD) and hemofiltration (HF).
• To investigate the impact of dialysate temperature on thermal balance in HD.
• To evaluate the contribution of thermal balance to vascular stability in online HF.

Main Methods:

• An in vitro study comparing conventional HD (37°C), cold HD (35.5°C), and pre- and post-dilution online HF (37°C).
• Measurement of thermal balance (kJ/h) across different dialysis modalities.
• Assessment of cardiovascular response and hemodynamic stability.

Main Results:

• Cold HD exhibited a more negative thermal balance (-130 kJ/h) compared to conventional HD.
• Post-dilution HF also resulted in a negative thermal balance (-75 kJ/h).
• Online HF showed minimal differences in thermal balance compared to conventional HD, with warm infusion making negative thermal balance unlikely.

Conclusions:

• While cold dialysate and HF influence thermal balance, vascular stability in online HF is not solely explained by thermal energy balance.
• Other factors likely contribute to the improved cardiocirculatory response observed in convective dialysis.
• Further research is needed to identify these additional factors influencing hemodynamic stability during dialysis.