SIRS & sepsis Flashcards
What is SIRS
Systemic inflammatory response syndrome
a self-amplifying, dysregulated systemic inflammatory response
What are PAMPs, DAMPs, and PRRs, and what are their roles in the immune response?
PAMPs (Pathogen-Associated Molecular Patterns):
- Found on pathogens
- Recognized by immune system to trigger immune response
- Help distinguish pathogens from self
DAMPs (Damage-Associated Molecular Patterns):
- Released by damaged cells
- Signal immune system to respond to tissue injury
PRRs (Pattern Recognition Receptors):
- Found on immune cells
- Detect PAMPs & DAMPs to activate inflammatory pathways
What is SIRS triggered by?
Burns
Neoplasia,
Pancreatitis (non equine)
How does SIRS affect coagulation?
It can result in coagulopathies and other clinical effects
What is the difference between SIRS and Sepsis?
Sepsis is SIRS caused by an infection
What is sepsis?
Exacerbated production of both pro- & anti-inflammatory cytokines
Hyperactive response to infection which could induce immune paralysis
What is severe sepsis?
Sepsis with organ hypo-perfusion or organ dysfunction
No predictive biomarkers or therapeutic targets yet
Clinical manifestations depend on infection site, microorganism, patient health, diagnosis & treatment
Spontaneous sepsis in equids—linked to bacterial endotoxin susceptibility
Give examples of the pro- & anti-inflammatory cytokines involved in sepsis
What is septic shock?
Severe sepsis + systemic hypotension, leading to subform of distributive shock
What are the clinical signs of septic shock?
Increased heart rate, decreased blood pressure, leukocytosis, increased adrenaline & noradrenaline
What is Multiple Organ Dysfunction Syndrome (MODS)?
Altered organ function in acutely ill animal where homeostasis cannot be maintained without intervention
What are the 2 classifications of MODS?
Primary MODS:
- Direct organ dysfunction due to a well-defined insult (e.g., burns, neoplasia)
Secondary MODS:
- Organ failure as a result of the host’s response (e.g., SIRS)
What is Disseminated Intravascular Coagulation (DIC)?
consumptive coagulopathy causing both excessive clotting and increased risk of bleeding
What are the main pathological changes in DIC?
Pathological activation of coagulation, leading to microvascular clotting
Haemorrhagic diathesis – impaired synthesis of clotting factors
Consumption of procoagulants – excessive use of clotting factors leads to their depletion
Excessive thrombin & fibrin generation – promotes widespread clot formation & platelet aggregation
Endothelial glycocalyx involvement – damage to endothelium exacerbates coagulation issues
What are common clinical signs of DIC in large animals?
Thrombosis rather than spontaneous hemorrhage
Petechial hemorrhages
Bleeding after trauma, venipuncture, surgical sites, or nasogastric intubation
What is DIC associated with?
SIRS, SEPSIS, SEPTIC SHOCK, MODS
Systemic neoplasia
Enteritis and colitis
What are the diagnostic criteria for DIC?
Presence of 3 out of 5 abnormalities:
- Thrombocytopenia (low platelet count)
- Prolonged prothrombin time
- Prolonged activated partial thromboplastin time
- Increased fibrin degradation products
- Decreased antithrombin III
What is the significance of D-dimers in DIC?
D-dimers are biomarkers of ongoing fibrin lysis, indicating active clot breakdown
