Some studies have shown that antiplatelets agents could reduce organ dysfunction in septic shock in mice and human models. Platelets are actors in immunity and their activation can be complicated by tissue damage with vascular occlusions which can lead to organ dysfunction. Investigators can hypothesize an increase in platelet activation and in leukocyte-platelet aggregates in septic shock.

Inclusion Criteria:

EXPERIMENTAL GROUP

• Patient who possibly gave an oral agreement to inclusion and may sign a consent once out of intensive care
• Patients hospitalized in general intensive care
• Patient hospitalized for less than 72 hours
• Patient suffering from severe sepsis, whatever their origin, with hypotension (PAs <90mmHg) despite adequate fluid resuscitation and vasoactive requiring the use of amines, with hypoperfusion and / or at least one organ dysfunction ( septic shock)
• Patient with a Sequential Organ Failure Assessment (SOFA) score> 8 (or> 2 in an organ) in the first 24 hours
• Patient enjoying a social security scheme or equivalent

CONTROL GROUP

• Signed informed consent
• Patient seen anesthesia consultation for orthopedic knee prosthesis of laying or hip with a negative balance infectious
• Patient enjoying a social security scheme or equivalent

Exclusion Criteria:

EXPERIMENTAL GROUP

• Patient on safeguarding justice, guardianship
• Patient suffering from a haematological malignancy (leukemia, lymphoma ...)
• Patient suffering from thrombocytopenia or constitutional thrombopathy
• Pregnant

CONTROL GROUP

• Patient on safeguarding justice, guardianship
• Patient with infectious positive balance (dental, urinary tract) prior to surgery
• Patient suffering from a haematological malignancy (leukemia, lymphoma ...)
• Patient suffering from thrombocytopenia or constitutional thrombopathy
• Pregnant