SIRS And MODS

Question 1

What is SIRS?

Answer 1

Systemic inflammatory response syndrome

Widespread systemic inflammation

Question 2

What are the hallmarks of SIRS?

Answer 2

Perfusion abnormalities
Disruption of microcirculation
Organ damage

** untreated, leads to MODS

Question 3

T/F: SIRS is always a secondary condition to an underlying disease process

Answer 3

True

Question 4

What are the diagnostic criteria for SIRS in the Canine??

Answer 4

Two or more of any of the following:

Temp either LOW(<100.6) or HIGH(102.6)
Heart rate HIGH (>120bpm)
Resp rate HIGH (>20bpm)
WBC either LOW (<6000) or HIGH (>16,000)

Question 5

What are the diagnostic criteria for SIRS in cats>

Answer 5

Three or more of the following..

Temp LOW (<100) or HIGH (104)
Heart rate LOW (<140) or HIGH (>225)
Resp rate HIGH (>40bpm)
WBC either LOW (<5000) or HIGH (>19000)

Question 6

You have identified SIRS in your patient.. what steps will you take in this patient??

Answer 6

Identify underlying dz or pathology

Rule out sepsis

Provide hemodynamic support

Identify, track,and support organ dysfunction

Treatment targeted to underlying dz

Question 7

Common sources of Infectious SIRS?

Answer 7

Septic peritonitis 
Pyothorax
Endocarditis 
Bacterial fasciitis 
Parvoviral enteritis

Question 8

Common sources of non-infectious SIRS?

Answer 8

Pancreatitis 
Immune mediated dz 
Heat stroke 
Trauma 
Burns

Question 9

If the patient fits SIRS criteria but you cannot find an underlying disease … what should you do?

Answer 9

KEEP LOOKING if patient is sick

Question 10

What is the definition of sepsis?

Answer 10

Systemic inflammatory response (SIRS) due to INFECTION

—can be caused by bacteria, fungus, virus, or protozoa

Question 11

What is the most common type of sepsis?

Answer 11

Gram negative — usually ecoli in the GI system

LPS is bound by LPS binding protein
Activated Toll like receptors and other pro inflammatory things in Tcells => leads to cytokine storm

Question 12

What is the neurohormonal response induced by SIRS?

Answer 12

Pro-inflammatory molecules induce …

Baroreceptor-mediated catecholamine release

Counterregulatory hormones

• glucagon
• ACTH
• cortisol

Question 13

T/F: septic patients also have SIRS

Answer 13

True

Sepsis is defined as SIRS + infection

Question 14

Signs of septic shock in dog?

Answer 14

Hyperdynamic
Hypermetabolic

Tachycardia 
Tachypnea 
Hyperemia 
Decreased CRT 
Pyrexia

Question 15

Signs of septic shock in cats?

Answer 15

Lethargic

Bradycardia
Hypothermic
Pale or icterus

Weak pulses

— never seen hyperdynamic phase, go straight to deocompensated state

Question 16

What clinical signs do you see in early decompensated sepsis?

Answer 16

Failure of compensatory responses

Hypotension and hypoperfusion
Collapse
Decreased mentation

Question 17

What are the goals of treatment for SIRS>

Answer 17

Hemodynamic optimization

IV fluids (hypovolemia)

Vasopressor therapy (refractory hypotension; distributive shock -> septic shock)

Resuscitation end points

Question 18

What type of early antibiotic therapy will you do for suspected sepsis patients?

Answer 18

4 quadrant therapy!

Gram pos
Gram neg
Aerobes
Anaerobes

Question 19

Should you ever delay early antibiotic treatment in sepsis to get a culture?

Answer 19

NO!

Better survival if antibiotics are started right away

Question 20

What is MODS?

Answer 20

Altered organ function in an acutely ill patient such that homeostasis cannot be maintained without intervention

Question 21

In what systems can organ dysfunction be seen in?

Answer 21

Endothelial

Cardiopulmonary

Renal

Hepatic

Nervous

Endocrine

GI

— all associated with progression of uncontrolled systemic inflammation and DIC

Question 22

T/F: there is an increase in mortality with the number or organ systems affected

Answer 22

True

Question 23

What is the pathophysiology leading to MODS?

Answer 23

SIRS (infectous or non-infectous) —> microvascular dysfunction causing altered blood flow, hypoxia, ischemia, DIC, and reperfusion injury —> MODS —> mortality

Question 24

When does SIRS become MODS?

Answer 24

When there is activation and dysregulation of the inflammatory cascade

Endothelial damage exposes tissue factor leading to coagulation derangement

Question 25

What are the three models of MODS?

Answer 25

1 hit model — result of a massive initial insult (eg trauma or septic peritonitis )

2-hit model — multiple insults: a priming insult followed by second hit —> exaggerated inflammatory response (eg aspiration pneumonia following trauma)

Sustained hit model— continuous insult (eg drug resistant bacterial infection)

Question 26

What are the mechanisms of organ dysfuntion>

Answer 26

Ischemia and reperfusion injury

Compartment syndrome

Bacterial translocation and endotoxemia

Endothelial cell activation and chemotaxis

Idiosyncratic drug reactions/toxicities

Question 27

What are risk factors for bacterial translocation across the GI mucosa?

Answer 27

Drugs - ulceration 
Metabolic disease 
Hypotension/ischemia 
Inflammatory disease 
Infectous disease 
Toxins
Neoplasia 
Paraneoplasic 

—> inflammation in occurring in response.. when you have ischemic gut that is reperfused, the inflammatory mediators are elaborated and distributed through the lymphatic to distant organs