Hyperosmolality, acetate, and lactate: dilatory factors during peritoneal dialysis

Area of Science:

• Physiology
• Nephrology
• Pharmacology

Background:

• Peritoneal blood flow influences solute clearance in peritoneal dialysis.
• Arteriolar vasodilation can increase solute delivery to peritoneal capillaries.

Purpose of the Study:

• To identify vasoactive effects of McGaw and Dianeal peritoneal dialysis solution components.
• To understand how solution composition alters in vivo peritoneal blood flow.

Main Methods:

• Used in vivo television microscopy to observe rat cremaster muscle arterioles.
• Quantitated arteriole diameter changes induced by varying solution composition.
• Investigated effects of hyperosmolality, dextrose, sucrose, sodium chloride, acetate, and lactate.

Main Results:

• Hyperosmolality from dextrose, sucrose, or NaCl induced submaximal arteriole dilation.
• Acetate or lactate solutions at normal osmolality caused slow, submaximal dilation.
• High osmolality acetate or lactate solutions rapidly induced maximal arteriole dilation.

Conclusions:

• Commercial dialysis solutions (McGaw, Dianeal) induced rapid, maximal vasodilation.
• This effect is attributed to the combined high osmolality and buffer anions (acetate/lactate).
• The findings suggest a mechanism for enhanced solute transport in peritoneal dialysis.