Endotoxin and Sepsis Lecture 15

Question 1

Endotoxin Structure

Answer 1

• Part of gram negative outer membrane
• O antigen, sugar moeities, and Lipid A
• Must be held together with KDO to be toxic
• Lipid A is the toxic portion

Question 2

Endotoxin Cellular Reactions

Answer 2

• Binds LBP and the complex then binds CD14, TLR4 on macrophages.
• Leads to release of vasoactive amines and cytokines.

Question 3

Sepsis Pathophys

Answer 3

• Release of vasoactive amines and cytokines causes leakage of fluid and inflammatory cells through endothelium.
• Also causes DIC and coagulation
• Results in hypotension and vascular occlusion leading to MOSF

Question 4

Sepsis Classifications

Answer 4

• Bacteremia: Cultures can be grown from blood
• Septicemia: Bacteria in blood with toxins released and toxic effects
• SIRS: 2/4 : Tachypnea, Tachycardia, Fever, Leukocytosis/Leukopenia. Hypotension also occurs.
• Sepsis: SIRS with known bacterial etiology

Question 5

Biochemical Markers of Sepsis

Answer 5

-Protein C which is an anticoagulant is decreased and D Dimer which is a breakdown product of Fibrin is increased.

Question 6

Treatment

Answer 6

-Fluid resuccitation is first
-Also find and treat with antibiotics the infection
-Can use presssors (dopamine and norepi)
Previously an artificial protein C Xigris which was pulled because of ineffectiveness.