The Effect of Crystalloids and Colloids on Visceral Blood Flow
Status:
Completed
Trial end date:
2011-03-01
Target enrollment:
Participant gender:
Summary
Patients often require fluid replacement during and after an operation. This is usually given
through veins in the arm using an intravenous cannula and doctors have traditionally used
fluid containing sodium chloride (saline). However accumulating evidence suggests that large
infusions of saline are associated with adverse physiological effects including acidification
of the blood and a rise in potassium and chloride levels. Studies in animals have shown that
high levels of chloride in the blood and excess saline can cause blood vessels in the kidney
to constrict leading possibly to a decrease in kidney function. Improvement in acid-base
balance and kidney function may be observed with balanced solutions containing constituents
that are more closely matched to the body's own fluid composition. However, little is known
about the physiological effects of these solutions as they have only recently been developed.
Magnetic resonance imaging (MRI) is a radiological modality which can now assess blood flow
and supply of the kidney noninvasively without the need for the injection of radiological
dyes known as contrast agents. This is now of major importance due to the possible adverse
effects of MRI contrast agents leading to Nephrogenic Systemic Fibrosis (NSF), a progressive
disease which has been observed in some kidney patients after receiving 'gadolinium based'
contrast agents. This has therefore led to increased interest and demand for noncontrast
based imaging methods. In this study we aim to compare the effects of balanced versus
unbalanced fluid infusions in healthy human volunteers:
We will aim to measure:
1. Blood biochemical composition and acidity
2. Kidney function and supply as measured by dynamic MRI