Haemorrhage & Shock

Question 1

What is meant by circulatory shock?

Answer 1

When the cardiovascular system is unable to provide adequate oxygen & nutrients for aerobic cellular respiration

Question 2

What are the signs of shock?

Answer 2

Pale, cold, sweaty, mottled skin
Pulse is weak and rapid
Pulse pressure is reduced
Low BP
Slow capillary refill
Tachypnoea
Urine output is reduced
Confusion
Weakness
Collapse
Coma

Question 3

What are they types of shock?

Answer 3

Hypovolaemic shock

Cardiogenic shock

Septic
Anaphylactic

Anaemic shock

Cytotoxic shock

Question 4

What is hypovolaemic shock?

Answer 4

Severe blood or fluid loss meaning the heart can’t pump enough blood around the body

Question 5

What causes hypovolaemic shock?

Answer 5

Blood loss:

• acute GI bleed
• Peri/post operative
• Splenic rupture

Fluid loss:

• Dehydration
• Burns
• Pancreatitis

Question 6

What is cardiogenic shock?

Answer 6

Inadequate tissue perfusion caused by cardiac pump failure

Question 7

What causes cardiogenic shock?

Answer 7

MI
Arrhythmia: V fib, etc
PE
Tension pneumothorax: pressure on mediastinum = no venous return to heart
Anything that causes pump failure

Question 8

How does sepsis cause shock?

Answer 8

Infection

Inflammatory response to bacteraemia
Histamine, NO, other inf mediators released
Affects small blood vessels
Vasodilation, leaky capillaries
Reduced blood volume

Coagulation cascade is disrupted which leads to DIC

Question 9

What is DIC?

Answer 9

Disseminated intravascular coagulation

Bacteraemia or trauma causes inappropriate widespread activation of coagulation cascade, formation of loads of blood clots in small vessels

Leads to the compromise of blood flow to tissue and organs

Since clotting factors and platelets are used up by the clots you get bleeding as well

Question 10

How does anaphylaxis cause shock?

Answer 10

Massive histamine release causes systemic vascular dilatation and leaky capillaries

Causing a hypovolaemia, hypotension

Question 11

What is neurogenic shock?

Answer 11

Injury to the CNS which causes loss of vascular tone, so blood flow is altered
I.e spinal injury?

Question 12

How would you manage septic shock?

Answer 12

BUFALO

Blood cultures
Urine output
Fluid resuscitation
Antibiotics
Lactate
Oxygen (HF, NRB mask)

Question 13

How would you manage anaphylactic shock?

Answer 13

ABCDE

Give IM adrenaline (epipen) 500mcg 1:1000
Anti-histamine: chlorphenamine 10mg
Hydrocortisone 200mg

Question 14

How would you treat hypovolaemic shock?

Answer 14

Give fluids

If haemorrhagic, give blood

Question 15

What are other symptoms of anaphylactic shock?

Answer 15

Breathlessness
Wheeze
Rash
Erythema
Angio-oedema

Question 16

Why does shock cause low BP?

Answer 16

Blood/fluid loss

Reduction in ventricular filling = fall in stroke volume + therefore BP

Question 17

Why does shock cause oliguria?

Answer 17

Reduced renal perfusion, reduced glomerular filtration

Question 18

What does ARDS stand for?

Answer 18

Acute respiratory distress syndrome

Question 19

What is ARDS?

Answer 19

Widespread inflammation in the lungs triggered by trauma, sepsis, etc.

Inflammation causes alveolar capillary membrane injury

Leading to impaired gas exchange in the lungs, so the body does not get enough oxygen

Question 20

What are the clinical features of ARDS?

Answer 20

Cyanosis
Tachypnoea
Tachycardia
Bi-lateral fine inspiratory crackles

Question 21

There are 3 phases in ARDS. What are they?

Answer 21

Exudative phase: accumulation of excessive fluid, protein + inflammatory cells in lungs

Proliferative phase: connective tissue & other structural elements proliferate in response

Fibrotic phase: scarring