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

Microcirculatory Alterations: Potential Mechanisms and Implications for Therapy
Daniel De Backer MD
2:00-2:15
Wednesday, February 15
Educational Objectives:
To understand the critical role of the microcirculation in fine tuning tissue perfusion.
To discuss what is the microcirculation, how it is regulated.
To discuss the potential mechanisms implicated in microcirculatory alterations and how this may impact therapy.
Content Description:
Multiple experimental studies have shown that sepsis is associated with alterations microcirculatory perfusion.
These alterations are characterized by heterogeneity of perfusion with capillaries with stop flow in close vicinity
to well perfused capillaries. This pattern has been observed in endotoxic models as well as in models with live
bacteria, in various species and in various organs. Different mechanisms have been implicated in the development
of these alterations including loss of communication between vascular segments, impaired endothelial
vasoreactivity, alterations in red and white blood cells rheology, alteration in endothelial glycocalyx, platelet
aggregation and microthrombosis. In addition to the alterations in microvascular perfusion, alteration in
microvascular endothelium is associated with activation of coagulation and inflammation, reactive oxygen
species generation and permeability alterations.
How to manipulate the microcirculation? Increasing flow without recruiting the microcirculation is ineffective,
according classical hemodynamic resuscitation has minimal impact on the microcirculation.
Suggested Reading:
1. De Backer,D.et al. (2002). Microvascular blood flow is altered in patients with sepsis. Am J Respir Crit
Care Med, 166, 98-104.
2. De Backer,D.et al. (2011). Microcirculatory alterations: potential mechanisms and implications for therapy.
Ann. Intensive Care, 1, 27.
3. Ellis,C.G. et al. (2002). Effect of a maldistribution of microvascular blood flow on capillary O(2) extraction
in sepsis. Am J Physiol, 282, H156-H164.
4. Sakr,Y. et al. (2004). Persistant microvasculatory alterations are associated with organ failure and death in
patients with septic shock. Crit Care Med, 32, 1825-1831.
5. Secor,D. et al. (2010). Impaired microvascular perfusion in sepsis requires activated coagulation and P-
selectin-mediated platelet adhesion in capillaries. Intensive Care Med, 36, 1928-1934.
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