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{ Shock & Sepsis by Dr. Mohamed Shatat Professor of Internal Medicine

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Page 1: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

{

Shock & Sepsis by

Dr. Mohamed Shatat

Professor of Internal Medicine

Page 2: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion
Page 3: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

{ Shock Definition: is a life-threatening medical condition of

low blood perfusion to tissues resulting in cellular injury and inadequate tissue function. The typical signs of shock are low blood pressure, rapid heart rate, signs of poor end-organ perfusion (i.e., low urine output, confusion, or loss of consciousness), and weak pulses.

Page 4: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

1-distributive

2- cardiogenic

3- hypovolemic

4- obstructive.

However, these are not exclusive, and many patients with circulatory failure have a combination of more than one form of shock (multifactorial shock).

: Classification Four types of shock are recognized:

Page 5: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

1- Hypovolemic shock

Blood loss:

1- External: -Trauma GIT bleeding

2- Internal : - Haematoma Haemothorax

Haemoperitonium

Plasma loss: e.g.: Burns

Exfoliative dermatitis

Fluids and electrolytes loss:

External: -e.g. vomiting and diarrhea

Internal: e.g. pancreatitis, Ascites.

Page 6: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion
Page 7: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion
Page 8: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

2-Cardiogenic shock -Arrhythmia

-Heart failure 2ry to myocardial infarction or cardiomyopathy.

-Acute valvular dysfunction

Page 9: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

3-Obstructive shock -Tension pneumothorax

- Pericardial disease (cardiac tamponade, constrictive pericarditis)

- Obstructive valvular disease

- massive pulmonary embolism

Page 10: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

4-Distributive shock:

Septic shock

Anaphylactic shock

Neurogenic shock

Vasodilator drugs

Acute adrenal insufficiency

Page 11: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion
Page 12: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

Diagnosis of Shock: -Systolic hypotension: systolic blood

pressure less than 90 mmHg -End organ hypoperfusion: rapid

thread pulse, decreased urine output, cold bluish mottled extremities, altered mental status, ischemic bowel disease, ischemic hepatitis.

-Altered mental status, agitation, lethargy, confusion, coma.

Page 13: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion
Page 14: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion
Page 15: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

Treatment of shock:

Goals of treatment:

-Central venous pressure (CVP): 11-13 cm water

-O2 saturation above 70%

- Cardiac index: 2-4 L/min/m2

- Mean arterial blood pressure: 65-90 mmHg

Page 16: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

N.B.: To calculate the Mean arterial blood pressure ( MAP) is to first calculate the pulse pressure (subtract the D BP from the SBP) and divide that by 3, then add the DBP:

MAP = 1/3 (SBP – DBP) + DBP

Page 17: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion
Page 18: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

Neurogenic shock

Page 19: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion
Page 20: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

Infection: Invasion of normally sterile host tissue by microorganisms

Bacteraemia: Viable bacteria in blood

Systemic inflammatory response syndrome (SIRS):The systemic inflammatory response to a variety of severe clinical insults. The response is manifested by two or more of the following:

Temperature >38°C or <36°C Heart rate >90 beats/min Respiratory rate >20 breaths/min or Paco2 <4.3

kPa White cell count >12×109/L, <4×109/L or >10%

immature forms

Terminology used in systemic

inflammation and sepsis

Page 21: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

Sepsis: SIRS resulting from documented infection

Severe sepsis: Sepsis associated with organ dysfunction,

hypoperfusion or hypotension. Hypoperfusion and

perfusion abnormalities may include, but are not

limited to, lactic acidosis, oliguria or an acute

alteration in mental state Septic shock: Severe sepsis with hypotension (systolic BP <90 mmHg

or a reduction of >40 mmHg from baseline) in the absence of other

causes for hypotension and despite adequate fluid resuscitation

Page 22: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

Shock is difficult to define. The term is

used to describe acute circulatory failure

with inadequate or inappropriately

distributed tissue perfusion resulting in

generalized cellular hypoxia.

Shock

Page 23: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

A subset of severe sepsis (SIRS) and defined as sepsis (SIRS) induced hypotension despite adequate fluid resuscitation along with the presence of hypoperfusion that may include, lactic acidosis, oliguria, or an acute alteration in mental status.

Infectious or non infectious triggers Cytokine and inflammatory mediator cascade cardiovascular dysfunction and microvascular injury Hypotension and shock

Septic Shock

Page 24: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

Sepsis is a form of severe infection (often with bacteraemia &/or their endotoxins contained within the cell wall of gram-negative bacteria or exotoxin released by gram-positive bacteria) in the presence of large areas of damaged tissue (e.g. following trauma or extensive surgery)

Pathogenesis:

Page 25: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

with prolonged/repeated episodes of hypoperfusion can trigger an exaggerated inflammatory response with systemic activation of leucocytes and release of a variety of potentially damaging

, local vasodilation, mediators''increased endothelial permeability, and activation of coagulation pathways.

Page 26: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

These mechanisms are in play during septic shock but on a systemic scale, leading to diffuse endothelial damage which itself can further activate inflammatory reactions,vascular permeability, vasodilatation, and coagulation cascades ended by thrombosis of end-organ capillaries and end-organ damage ; with multiple organ failure (MOF).

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Page 28: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

Arachidonic acid metabolites

Complement system.

IL-1, IL-6, TNF-alpha - Released by mast cells

Coagulation cascade (DIC) and end-organ damage.

Catecholamines -

Glucocorticoids -

Bradykinin - Contributes to vascular leak

Histamines - Released by mast cells

The following systems and mediators are activated in septic shock:

Page 29: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion
Page 30: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

The brain and kidneys are normally protected from swings in blood pressure by autoregulation:

In early sepsis - autoregulation curve shifts rightwards (due to increase in sympathetic tone).

In late sepsis: - vasoparesis occurs - autoregulation fails "Steal phenomena" may occur (areas of

ischaemia may have their blood stolen by areas with good perfusion).

Multiple Organ Failure (MOF) in septic shock:

Page 31: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

1-Heart

Depressed myocardial contractility due to:

Myocardial oxygen supply is dependent on diastolic blood pressure (which is decreased).

Increased circulating myocardial depressant factor.

2-Lungs

Ventilation / perfusion mismatches -Initially due to increased dead space

-Subsequently due to shunt

Acidosis - tachypnoea decreased PaCO2

Nosocomial pneumonia (about 70%).

Page 32: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

3-Kidneys

Oliguria & Renal failure (pre renal type) due to intravascular dehydration, circulating nephrotoxins, drugs.

4-Liver

ICU jaundice

Uncontrolled production of inflammatory cytokines by the kuppfer cells (of the liver), primed by ischemia and stimulated by endotoxin (derived from the gut), leads to cholestasis and hyperbilirubinaemia.

Page 33: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

• GUT mucosa is usually protected from injury by autoregulation.

* Hypotension and hypovolaemia leads

superficial mucosal injury which leads to atrophy and translocation of bacteria into the portal circulation reaching to the liver and stimulate liver macrophages causing cytokine release and amplification of SIRS.

Splanchnic Circulation-5

Page 34: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

6- CNS

Confusion / stupor / coma secondary to:

Hypoperfusion injury

Septic encephalopathy

Metabolic encephalopathy

Drugs

7- Metabolic

Hyperglycaemia due to sepsis & catecholamines (both cause insulin resistance)

Lactic acidosis

Muscular breakdown

Generalized catabolic state

Page 35: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

Temperature increased or decreased

White cell count increased or decreased

Rigors

Sweating

Nausea and vomiting

Tachycardia

Hypotension

Tachypnoea (acute lung injury)

Signs and Symptoms of Sepsis:

Page 36: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

Warm pink peripheries

Confusion

Oliguria

increased Glucose

increased Lactate

increasingly negative Base excess

decreased Albumin

increased INR, increased APTT , decreased Platelets, DIC

Jaundice

Page 37: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

Urine: Culture and Sensitivity.

Nasal & throat swabs

Blood cultures

Sputum specimen [protected sample]

Pus / wound swabs

Serological tests

Echocardiogram [heart valves]

Dental examination

X - ray of sinuses

Abdominal ultrasound

Laparotomy

Radiolabelled White Cell Scan

Investigation of sepsis of unknown origin:

Page 38: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion

Monitoring of: Blood pressure , Central venous pressure (CVP)

, Pulmonary artery pressure, urine output

A patent airway must be maintained and oxygen must be

given.

The underlying cause should be corrected

Preload and volume replacement therapy under monitoring.

Coagulopathy defects should be corrected

Metabolic disturbances (acidosis/alkalosis ) should be

corrected

impaired Myocardial contractility should be corrected

Good coverage by potent broad spectrum antibiotic

combination

Management of a septic patient:

Page 39: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion
Page 40: Shock & Sepsis - Minia new... · Sepsis: SIRS resulting from documented infection Severe sepsis: Sepsis associated with organ dysfunction, hypoperfusion or hypotension. Hypoperfusion