Effects of plasma viscosity modulation on cardiac function during moderate hemodilution

Area of Science:

• Cardiovascular Physiology
• Hemodynamics
• Biomaterials Science

Background:

• Increasing plasma viscosity during hemodilution can impact microvascular hemodynamics.
• Cardiac function is influenced by changes in blood viscosity, pressure drop, and flow rate.
• Understanding plasma viscosity effects on cardiac function during hemodilution is crucial.

Purpose of the Study:

• To investigate the effects of varying plasma viscosity on cardiac function during acute isovolemic hemodilution.
• To compare the cardiac functional outcomes of different plasma expanders with distinct viscosities.

Main Methods:

• Acute isovolemic hemodilution of 40% blood volume using three plasma expanders: high (Dx2M), moderate (Dx70), and low (PEG-HSA) viscosity.
• Cardiac function was assessed using a miniaturized pressure-volume conductance catheter.

Main Results:

• Hemodilution reduced pressure to 78-84% of baseline across expanders.
• Cardiac output significantly increased with Dx2M and PEG-HSA.
• Dx2M demonstrated significantly higher stroke work compared to Dx70.

Conclusions:

• Low-viscosity PEG-HSA hemodilution beneficially affected cardiac function, comparable to high-viscosity Dx2M.
• PEG-HSA prevented potential negative effects of increased peripheral vascular resistance associated with higher plasma viscosity.
• These findings suggest that maintaining low plasma viscosity during hemodilution is advantageous for cardiac function.