Download MBBS General Surgery PPT 13 Systemic Inflammatory Response Syndrome Lecture Notes

Download MBBS (Bachelor of Medicine, Bachelor of Surgery) General Surgery PPT 13 Systemic Inflammatory Response Syndrome Lecture Notes

Systemic Inflammatory Response

Syndrome,MODS,Sepsis

Infection

Presence of organisms in a closed space or

location
where not normally found

Infection


SIRS: Systemic Inflammatory Response Syndrome

A clinical response arising from a

nonspecific insult manifested by 2 of the

fol owing:

? Temperature: 38?C or 36?C
? HR: 90 beats/min
? Respirations: 20/min
? WBC count: 12,000/mL or 4,000/mL

or >10% immature neutrophils

Sepsis: More Than Just Inflammation

Sepsis:

? Known or suspected infection

? SIRS criteria
Severe Sepsis: Acute Organ Dysfunction

? Severe Sepsis =

Sepsis with signs of acute organ

dysfunction in any of the fol owing

systems:

? Cardiovascular (septic shock)

? Renal

? Respiratory

? Hepatic

? Hemostasis

? CNS

? Unexplained metabolic acidosis

Sepsis: A Complex Disease
Septic Shock:

Sepsis induced with hypotension despite adequate resuscitation along with

the presence of perfusion abnormalities which may include, but are not limited

to lactic acidosis, oliguria, or an acute alteration in mental status

Multiple Organ Dysfunction Syndrome (MODS):

Presence of altered organ function in an acutely il patient such

that homeostasis cannot be maintained without intervention
Infection

Physiologic

Inflammation

Biochemical

Severe

Sepsis

Specific Organ

Severity

Predisposition

? Pre-existing disease

? Cardiac, Pulmonary, Renal

? HIV

? Age (extremes of age)
? Gender (males)
? Genetics

? TNF polymorphisms (TNF promoter high secretor genotype)
Response

Physiology

Markers of Inflammation

? Heart rate

? TNF

? Respiration

? IL-1

? Fever

? IL-6

? Blood pressure

? Procalcitonin

? Cardiac output

? PAF

? WBC

? Hyperglycemia

Organ Dysfunction

? Lungs

? Adult Respiratory Distress Syndrome

? Kidneys

? Acute Tubular Necrosis

? CVS

? Shock

? CNS

? Metabolic encephalopathy

? PNS

? Critical Il ness Polyneuropathy

? Coagulation

? Disseminated Intravascular Coagulopathy

? GI

? Gastroparesis and ileus

? Liver

? Cholestasis

? Endocrine

? Adrenal insufficiency

? Skeletal Muscle

? Rhabdomyolysis












Sepsis: Defining a Disease Continuum

Infection/

Trauma

SIRS Sepsis Severe Sepsis

A clinical response arising

SIRS with a presumed or

from a nonspecific insult,

confirmed infectious

including 2 of the following:

process

? Temperature 38oC or

36oC

? HR 90 beats/min
? Respirations 20/min
? WBC count 12,000/mm3

or

4,000/mm3 or >10%

immature neutrophils

Sepsis: Defining a Disease Continuum

Infection/

Trauma

SIRS Sepsis Severe Sepsis

? Sepsis with 1 sign of organ failure

? Cardiovascular (refractory

hypotension)

? Renal

? Respiratory

? Hepatic

Shock

? Hematologic

? CNS

? Unexplained metabolic

acidosis


Pathogenesis of SIRS/MODS

Preoperative Il ness

Trauma or Operation

Tissue Injury

optimal oxygen delivery

Inadequate

Excessive

and support

Resuscitation

Inflammatory

Response

Recovery

SIRS/MODS

Initiation of Inflammatory Response

From Wheeler & Bernard, NEJM 1999


Homeostasis is unbalanced in Severe Sepsis

Carvalho AC, Freeman NJ. J Crit Il ness. 1994;9:51-75; Kidokoro A et al. Shock. 1996;5:223-8;

Vervloet MG et al. Semin Thromb Hemost. 1998;24:33-44.

Coagulation and Fibrinolysis

Bernard, GR. NEJM 2001;344;10:699-709


Pathogenesis of SIRS/MODS

Preoperative Illness

Trauma or

Operation

Tissue Injury

optimal oxygen

Inadequate

Excessive

delivery and support

Resuscitation

Inflammatory

Response

Recovery

SIRS/MODS

Regulation of oxygen delivery

Normal

Abnormal

Cardiac

output

BP=CO * SVR

Cardiac

Output

regional distribution

regional distribution

Intra Organ Distribution

Intra Organ Distribution

Microcirculation

Microcirculation

QO2 = Flow * O2 content
Oxygen Delivery

? Delivery: Demand mismatch
? Diffusion limitation (edema)

Oxygen Consumption

H+

H+

Cytc

H+

H+

I

Q

III

IV

NADH + H+

H+

1/2 O2 + H+ H2O

NAD+

ADP + Pi

ATP

?Pyruvate Dehydrogenase (PDH) activity decreased

?Decreased delivery of Acetyl CoA to TCA cycle

?Mitochondrial dysfunction


Severe Sepsis:

The Final Common Pathway

Endothelial Dysfunction and Microvascular

Thrombosis

Hypoperfusion/Ischemia

Acute Organ Dysfunction

(Severe Sepsis)

Death
Components:

? Early Recognition

? Early Goal-Directed Therapy

? Monitoring

? Resuscitation

? Pressor / Inotropic Support

? Steroid Replacement

? Recombinant Activated Protein C

? Source Control

? Glycemic Control

? Nutritional Support

? Adjuncts:

? Stress Ulcer Prophylaxis, DVT Prophylaxis, Transfusion, Sedation, Analgesia,

Organ Replacement