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Flashcards in Shock Deck (32):
1

Name the four types of shock.

Hypovolaemic
Cardiogenic
Maldistributive
Obstructive

2

What is the cause of hypovolaemic shock?

Loss of 20% or more of circulating volume

3

What is the cause of cardiogenic shock?

Failure of the heart to act as an effective pump

4

What is the cause of obstructive shock?

Mechanical impediments to forward flow, e.g. blocked circulation

5

What is the cause of maldistributive shock?

Abnormalities of the peripheral circulation, e.g. dilated arteries

6

What is shock?

Describes acute circulatory failure with inadequate or inappropriately distributed tissue perfusion

7

Which type of shock is associated with sepsis?

Maldistributive shock

8

What is a good biomechanics marker for the severity of shock?

Lactic acid

9

What are the three stages of shock?

Non-progressive
Progressive
Irreversible

10

What is the sympathetic response to shock?

Hypotension causes increased sympathetic activity with noradrenaline release
Results in vasoconstriction, increased myocardial contractility and heart rate

11

What does the adrenal medulla produce in response to shock?

Catecholamines, specifically adrenaline

12

What is the renal response to hypotension?

renal-angiotensin-aldosterone pathway

13

What is the renin-angiotensin-aldosterone pathway?

Reduction in perfusion in renal cortex stimulates release of renin.
Renin converts angiotensinogen to angiotensin I, which in the lungs is converted to angiotensin II.
Angiotensin II stimulates secretion of aldosterone from adrenal cortex.

14

In the long-term, what occurs in non-progressive shock?

Internal transfusion
More glucose produced

15

What is internal transfusion?

Body tries to move fluid from interstitial to vasculature by decreasing BP, which decreases capillary hydrostatic pressure

16

What happens when fluid loss exceeds 30%?

It becomes progressive shock

17

What happens in progressive shock?

Increased vascular permeability
Further decrease in blood volume
Further tissue damage
Impaired tissue perfusion and gas exchange

18

What is the golden hour?

The hour after the start of rapid blood/fluid loss where rapid treatment will be most effective

19

What is irreversible shock caused by?

Prolonged fluid loss causing irreversible damage to the heart

20

What is SIRS?

Systemic inflammatory response syndrome - an inflammatory state affecting the whole body, usually in response to infection

21

What is SIRS usually related to?

Sepsis

22

How is SIRS defined?

Having two or more of the following features:
Temp >38 or 90)
Tachypnoea (>20 RR)
High white cells (>12 x10l)

23

What does DIC stand for?

Disseminated intravascular coagulation

24

What is DIC?

Widespread activation of blood coagulation, due to release of procoagulants into the circulation

25

What is sepsis?

Systemic inflammatory response to infection, marked by characteristic haemodynamic disturbance or organ dysfunction

26

Why is there refractory hypotension in septic shock?

Low systemic vascular resistance
Low central venous pressure
Pulmonary artery occlusion pressure

27

How is sepsis diagnosed?

Clinical recognition

28

What are the clinical manifestations of sepsis?

Fever
Confusion
Tachycardia
Tachypnoea
Hypotension

29

Why is there 'warm shock' in septic shock?

Decreased BP is due to increased cardiac output and decreased peripheral resistance
Also there is normal stroke volume

30

What is ARDS?

Acute respiratory distress syndrome
Decreased compliance of vessels and decreased oxygen exchange

31

What should be given urgently in sepsis to increase chance of survival?

Antimicrobial agent

32

What does haemodynamic support involve?

Maintaining cardiac output
Ensure sufficient arterial blood pressure to perfuse organs