ABSTRACTS from 16th International COnference on ... - CRRT Online

Educational Objectives:
The Endothelial Glycocalyx: A New Target in Critical Illness
Can Ince PhD
2:15-2:30
Wednesday, February 15
Discuss the morphology, composition and physiology of the endothelial glycocalyx
Present methods of assessing the presence of the glycocalyx
Discuss the how the glycocalyx is compromised, its pathophysiological consequences and the factors which contribute
to its shedding.
Content Description:
The endothelial glycocalyx is an intraluminal layer of about 0.2µm covering the endothelial cells of blood vessels.
It is a compressible gel-like layer consisting of a web-like structure of membrane-bound glycoproteins and
proteoglycans.
The endothelial glycocalyx exerts a wide array of protective effects for the vasculature via inhibition of coagulation
and leucocyte adhesion, contributing to anti-oxidant compounds, contributing to the vascular permeability
barrier and by mediating shear stress-induced NO release. Demonstrating its presence and its compromise has
been technically very challenging which why its presence and significance has only recently come to light. Its
compromise is detected under vital or electron microscopy or by the presence of components of the shredded
glycocalyx in plasma. Its degradation is partially sensitive to reactive oxygen species and disease states associated
with activation of oxidative stress such as diabetes and sepsis as well probably a host of other diseased states
where inflammatory activation and oxidative stress are present. The appreciation of its presence and physiological
function has led to a re-appraisal of the view of fluid resuscitation as a means of treating hypovolemia and
maintaining intraluminal volume. In this respect there has been a reappraisal of the understanding of Starlings
principle in describing the effects of colloids. It is clear that future will be focused on protective strategies aimed
at the glycocalyx as well as novel fluid taking the importance the glycocalyx into account. Methods under development
using high resolution vital microscopy to assess the presence of the glycocalyx at the bedside may prove
useful in this respect.
Suggested Reading:
Nieuwdorp M, Meuwese MC, van Lieshout MHP, Levi M, Meijers JCM, Ince C, Vink H, Kastelein JJP, Erik
SG Stroes ESG (2009) TNF· inhibition dampens endotoxin-induced endothelial glycocalyx perturbation and
inflammatory effects in vivo. Atherosclerosis. 202(1):296-303.
Nieuwdorp M, Meuwese MC, Hans L Mooij HL, Ince C, BroekhuizenLN, Kastelein JP, Stroes ESG, Vink H
(2008) Measuring endothelial glycocalyx dimensions in humans: a novel tool to monitor vascular vulnerability. J
of Applied Physiol 104(3):845-52
Nieuwdorp M, Mooij HL, Kroon J, Atasever B, Spaan JA, Ince C, Holleman F, Diamant M, Heine RJ, Hoekstra
JB, Kastelein JJ, Stroes ES, Vink H. (2006) Endothelial glycocalyx damage coincides with microalbuminuria in
type 1 diabetes. Diabetes. Apr;55(4):1127-32
Vink H and Duling BR. Identification of distinct luminal domains for macromolecules, erythrocytes, and leukocytes
within mammalian capillaries. Circ Res 79: 581-589, 1996.
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