SHOCK

Alnasser AbdulazizAlomari MohammedAlhomoud Homoud

Objective Definition .Pathophysiology .Sign and symptoms .Types of shock .Management .Summery .

3

WHAT IS SHOCK?

Inadequate Tissue

Perfusion

• Shock is the term used to describe acute circulatory failure with inadequate or inappropriately distributed tissue perfusion resulting in generalized cellular hypoxia and/or an inability of the cells to utilize oxygen.

4

PATHOPHYSIOLOGY OF SHOCK

• The manifestation of shock reflects both –The impaired perfusion of body tissue

& –The body’s attempt to maintain tissue

perfusion (compensatory mechanism)

5

Inadequate tissue perfusion

Decreased oxygen supply

Anaerobic metabolism

Accumulation metabolic waste & lactate

Cellular failure (limited ATP produce)

Pathophysiology of shockcellular responses

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VICIOUS CYCLE Hypoperfusion

Cellular injury

Inflammatory mediators

Functional & structural changes in microvascular

circulation

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Global Tissue Hypoxia

• Endothelial inflammation and disruption• Inability of O2 delivery to meet demand• Result:

• Lactic acidosis• Cardiovascular insufficiency• Increased metabolic demands

8

Symptoms of Shock

• Anxiety /Nervousness

• Dizziness• Weakness• Faintness• Nausea & Vomiting• Thirst• Confusion• Decreased UO

• Hx of Trauma / other illness

• Vomiting & Diarrhoea

• Chest Pain• Fevers / Rigors• SOB

General Symptoms Specific Symptoms

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Signs of ShockPale

Cold & Clammy skin SweatingCyanosis

TachycardiaTachypnoea

Confused / AggiatatedUnconsciousHypotensiveStridor / SOB

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TYPES OF SHOCK

HYPOVOLEMIC

CARDIOGENIC

DISTRIBUTIVE

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Hypovolaemic

• Volume Loss

• Blood loss -HaemorrhagePlasma Loss -Burns ECF Loss - Vomiting & Diarrhoea

12

Compensatory mechanism and shock

Fluid

Volume

(CVP/JVP)

Vascular

Diameter

(SVR)

Cardiac

Output

(SV x HR)

PRE-LOAD AFTER-LOAD

13

Hypovolaemic shock

Fluid

Volume

(CVP/JVP)

Vascular

Diameter

(SVR)

Cardiac

Output

(SV x HR)

PRE-LOAD AFTER-LOAD

1

14

Hypovolaemic shock

Fluid

Volume

(CVP/JVP)

Vascular

Diameter

(SVR)

Cardiac

Output

(SV x HR)

PRE-LOAD AFTER-LOAD

12

15

Hypovolaemic shock

Fluid

Volume

(CVP/JVP)

Vascular

Diameter

(SVR)

Cardiac

Output

(SV x HR)

PRE-LOAD AFTER-LOAD

312

Hypovolaemic shock Management

• Hemorrhage: Arrest of bleeding & fluid resuscitation.

• Two wide bore (14-16 gauge) peripheral venous access.

• Crystalloid infusion- titrated to clinical response.

• PRBCs: Life threatening/ continued bleeding.

• Diagnosis & treatment: Source of bleeding/ other causes

• Invasive monitoring.

• Urine output monitoring- Foley catheter

17

Cardiogenic

• Pump FailureMay be due to – Inability of heart to Contract or– Inability of heart to pump blood

• Myocardial damage ( M.I)• Arrhythmias• Valvular damage

18

Compensatory mechanism and shock

Fluid

Volume

(CVP/JVP)

Vascular

Diameter

(SVR)

Cardiac

Output

(SV x HR)

PRE-LOAD AFTER-LOAD

19

Cardiogenic shock

Fluid

Volume

(CVP/JVP)

Vascular

Diameter

(SVR)

Cardiac

Output

(SV x HR)

PRE-LOAD AFTER-LOAD

1

20

Cardiogenic shock

Fluid

Volume

(CVP/JVP)

Vascular

Diameter

(SVR)

Cardiac

Output

(SV x HR)

PRE-LOAD AFTER-LOAD

21

21

Cardiogenic shock

Fluid

Volume

(CVP/JVP)

Vascular

Diameter

(SVR)

Cardiac

Output

(SV x HR)

PRE-LOAD AFTER-LOAD

3 21

Cardiogenic Shock management

• Maintenance of adequate oxygenation.• Carful fluid administration to avoid fluid

overload.• Cardiology consultation.• Thoracocenteasis, pericardiocentesis in

trauma.

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Distributive

• Decreased Peripheral Vascular Resistance

• Septic Shock (inflammatory mediators)• Neurogenic Shock (loss of sympathetic control

on vascular tone)• Anaphylactic shock (presence of vasodilator

substances like histamine)

24

Compensatory mechanism and shock

Fluid

Volume

(CVP/JVP)

Vascular

Diameter

(SVR)

Cardiac

Output

(SV x HR)

PRE-LOAD AFTER-LOAD

25

Distributive shock

Fluid

Volume

(CVP/JVP)

Vascular

Diameter

(SVR)

Cardiac

Output

(SV x HR)

PRE-LOAD AFTER-LOAD

1

26

Distributive shock

Fluid

Volume

(CVP/JVP)

Vascular

Diameter

(SVR)

Cardiac

Output

(SV x HR)

PRE-LOAD AFTER-LOAD

2 1

27

Distributive shock

Fluid

Volume

(CVP/JVP)

Vascular

Diameter

(SVR)

Cardiac

Output

(SV x HR)

PRE-LOAD AFTER-LOAD

32 1

septic shock management

• Crystalloid infusion ( target CVP ≥8 mmHg).• Urine output: ≥0.5 ml/kg/hr.• Vasopressors(noradrenaline):Persistent hypotension, after

volume restoration- • Serum lactate: Monitor tissue perfusion.• Identification of underlying infection: History, examination &

investigations (blood culture, radiological).• Treatment of infection: IV antibiotics(empirical, post-culture)

Neurogenic shock management

• Airway secured, adequate ventilation.

• Fluid resuscitation to restore intravascular volume.

• Administration of vasopressor.

Anaphylactic shock management

• Stop administration of causative agent.

• Maintain airway, give 100% O₂.

• Adrenaline 0.5-1 mg IM.

• IV crystalloid.

• 2nd line: Antihistamine- chlorphenamine 1—20 mg slow IV or

Hydrocortisone 200 mg IV

Shock Types & Physiology

Shock CVP CO PVRHypovolemic ↓ ↓ ↑Septic ↓ ↑ ↓Cardiogenic ↑ ↓ ↑Neurogenic ↓ ↓ ↓Anaphylactic ↓ ↑ ↓

Thank you