Intravascular retention

The theoretical advantage of colloids is their prolonged intravascular retention time compared to crystalloid solutions. Isotonic crystalloid solutions have substantial interstitial distribution within minutes of IV administration, but colloids remain in the intravascular space for hours or days, depending on factors such as capillary permeability. However, even with intact capillary permeability, the colloid molecules eventually leak through capillary membranes. 

In the above relationships, u (t) is the step Heaviside function. The Laplace transform of the intravascular retention-time distribution is... 

Zekom, D. Intravascular retention, dispersal, excretion and break-down of gelatin plasma substitutes, in Modified Gelatins as Plasma Substitutes Bibl Haematol 33, p. 131, Basel-New York, Karger 1969... 

Gadomer is a new promising agent for MRI. Due to its intravascular retention widiin the first minutes after i.v. administration, a variety of clinical applications are anticipated, most interestingly its use in cardiac imaging. The con und is safe, very well tolerated and completely excreted from the body. It is the first gadolinium containing dendrimer in pharmaceutical development. 

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