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Flashcards in Cardiovascular Response to Shock Deck (32)
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1

What is shock?

An abnormality of the circulatory system resulting in inadequate tissue perfusion and oxygenation

2

Results of shock?

Inadequate tissue perfusion
Inadequate oxygenation
Anaerobic metabolism
Accumulation of metabolic waste products
Cellular failure

3

MAP equation

Cardiac Output (CO) x Systemic Vascular Resistance (SVR)

4

What does adequate tissue diffusion depend on?

Adequate BP
Adequate Cardiac output

5

Cardiac output equation?

SV x HR

6

Things that affect Stroke volume?

Myocardial contractility - how strong heart contracts
Afterload - resistance
Preload-venous return

7

Different types of shock?

Cardiogenic
Obstructive
Hypovolaemic
Distributive

8

Patients can have different types of shock at the same time. True or False?

True

9

Hypovolaemic shock? Flow diagram

Loss of blood volume
|
Decreased blood volume
|
Decreased venous return
|
End diastolic volume
|
Decreased Stroke volume
|
Decreased CO and Decreased BP

10

What is cardiogenic shock?

Sustained hypotension caused by decreased cardiac contractility

11

Cardiogenic shock flow diagram?

Decreased cardiac contractility
|
Decreased stroke volume
|
Decreased cardiac output
|
Inadequate tissue perfusion

12

Flow diagram of tension pneumothorax (obstructive shock?

Increased intrathoracic pressure (in pleural cavity)
|
Decreased venous return (pressure gradient has changed)
|
Decreased EDV
|
Decreased SV
|
Decreased CO and decreased BP
|
Inadequate tissue perfusion

13

Neurogenic shock flow diagram?

Loss of sympathetic tone to blood vessels and heart
|
Massive venous and arterial vasodilation- affects heart rate
|
Decreased venous return & decreased SVR (TPR)
|
Decreased HR (UNLIKE other types of shock)
|
Decreased CO & decreased BP

14

Why is neurogenic shock unique?

It causes a decreased HR which is unlike other types of shock. This is because there is loss of sympathetic tone to blood vessels and heart

15

Vasogenic shock flow diagram?

Release of vasoactive mediators
|
Massive venous & arterial vasodilation- also increased capillary permeability
|
Decreased venous return & decreased SVR (TPR)
|
Decreased CO & decreased BP
|
Inadequate tissue perfusion

16

4 general steps to treatment of shock?

1) ABCDE approach
2) High flow Oxygen
3) Volume replacement - EXCEPT cardiogenic
4) Call for help early

17

Treatment of cardiogenic shock?

Inotropes

18

Treatment for tension pneumothorax?

Immediate chest drain

19

Treatment for anaphylactic shock?

Adrenaline

20

Treatment for septic shock?

Vasopressers

21

Causes of hypovolaemic shock?

Haemorrhage- trauma, surgery, GI haemorrhage

22

What does haemorrhage result in?

Decrease in blood volume, decreased Cardiac output, circulatory shock (reduced MAP)

23

haemorrhage shock response?

Compensatory mechanisms can maintain BP until more than 30% of blood volume is lost

24

What is observed in haemorrhagic shock?

Tachycardia
Small volume pulse
Cool peripheries
Decreased MAP (if blood loss is more that 30%)

25

Types of hypovolaemic shock?

Haemorrhagic and non-haemorrhagic

26

Types of cardiogenic shock?

Acute myocardial infarction

27

Types of obstructuve shock?

Cardiac temponade
Tension pneumothorax
Pulmonary embolism
Severe aortic stenosis

28

Types of distributive shock?

Neurogenic- eg spinal cord injury
Vasoactive- eg septic shock, anaphylactic shock

29

Caused of decreased blood volume?

Haemorrhage
vomiting
Diarrheoa
Excessive sweating

30

Why does tachycardia occur?

Increased HR due to baroreceptor reflex