Microvascular resuscitation as a therapeutic goal in severe sepsis.
Sepsis causes microvascular dysfunction. Increased heterogeneity of capillary blood flow results in local tissue hypoxia, which can cause local tissue inflammation, impaired oxygen extraction, and, ultimately, organ dysfunction. Microvascular dysfunction is clinically relevant because it is a marker for mortality: it improves rapidly in survivors of sepsis but fails to improve in nonsurvivors. This, along with the fact that resuscitation of mean arterial pressure and cardiac output alone fails to improve microvascular function, means that microvascular resuscitation is therefore a therapeutic goal. In animal studies of sepsis, volume resuscitation improves microvascular permeability and tissue oxygenation, and leads to improved organ function, including a reduction in myocardial dysfunction. Microvascular resuscitation strategies include hemodynamic resuscitation using the linked combination of volume resuscitation, judicious vasopressor use, and inotropes and vasodilators. Alternative vasoactive agents, such as vasopressin, may improve microcirculatory function to a greater degree than conventional vasopressors. Successful modulation of inflammation has a positive impact on endothelial function. Finally, targeted treatment of the endothelium, using activated protein C, also improves microvascular function and ultimately increases survival. Thus, attention must be paid to the microcirculation in patients with sepsis, and therapeutic strategies should be employed to resuscitate the microcirculation in order to avoid organ dysfunction and to reduce mortality.
Bateman
Ryon M
RM
The James Hogg Imaging, Cell Analysis, and Phenotyping Toward Understanding Responsive, Reparative, Remodelling, and Recombinant Events Centre for Cardiovascular and Pulmonary Research, University of British Columbia, Vancouver, Canada.
Walley
Keith R
KR
D000818:Animals; D000925:Anticoagulants / Q000627:therapeutic use; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D008833:Microcirculation / Q000187:drug effects* / Q000503:physiopathology; D011486:Protein C / Q000627:therapeutic use*; D012151:Resuscitation / Q000379:methods*; D018805:Sepsis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D014662:Vasoconstrictor Agents / Q000627:therapeutic use*
D000925:Anticoagulants; D011486:Protein C; D014662:Vasoconstrictor Agents