ST4 - Critical Illness

Question 1

What is the definition of shock?

Answer 1

Acute circulatory failure with inadequate or inappropriately distributed tissue perfusion (systolic<90mmhg)

Question 2

What is hypovolaemic shock, and what can cause it?

Answer 2

Loss of intravascular volume, caused by: - Haemorrhagic shock (trauma, GI bleeding, AAA) - DKA - GI fluid loss - Extensive burns - Fluid loss from fistulae or drains

Question 3

How is hemorrhagic shock classified?

Answer 3

1 - <750ml lost, no physiological changes 2 - 750-1500ml lost, pale/cold/clammy, parameters raised 3 - 1500-2000ml lost, altered mental state 4 - >2000ml lost, close to cardiac arrest As stages increase, pulse pressure becomes narrower, resp rate and heart rate increase, and urine output decreases

Question 4

What is distributive shock, and what causes it?

Answer 4

Vasodilation with increased capillary permeability and reduced vascular resistance, caused by: - Sepsis - Anaphylaxis - Neurogenic shock (spinal cold injury) - Endocrine failure (Addison’s)

Question 5

What is obstructive shock, and what causes it?

Answer 5

Physical obstruction to blood flow in the great vessels or the heart itself, caused by: - Tension pneumothorax - Massive PE - Cardiac tamponade

Question 6

What is cardiogenic shock, and what causes it?

Answer 6

Pump failure, caused by: - MI - Arrythmia - Myocarditis - Cardiac tamponade

Question 7

What is dissociative shock, and what causes it?

Answer 7

Oxygen unable to enter the cells, due to: - Cyanide poisoning

Question 8

What are some compensatory mechanisms in shock?

Answer 8

Increased RR - blow off C02 from acidosis Vasoconstriction - adrenaline released in response to hypotension Decrease in urine output - low BP causes ADH production

Question 9

What are the four stages of shock?

Answer 9

1. Initial 2. Compensatory 3. Progressive - failure of compensatory mechanisms 4. Refractory - vital organs have failed, death imminent

Question 10

How should anaphylactic shock be managed?

Answer 10

IM adrenaline (500mcg) IV fluid bolus Steroids (hydrocortisone) Antihistamines (chlorphenamine)

Question 11

How should cardiogenic shock be managed?

Answer 11

MONA (morphine, oxygen, nitrates, aspirin) DONT give fluids

Question 12

How should tension pneumothorax be managed?

Answer 12

Needle thoracocentesis - to drain air 02

Question 13

How should hemorrhagic shock be managed?

Answer 13

FIND THE CAUSE AND TREAT IT RESTORE CIRCULATING VOLUME - O negative blood (large bore IV), IV fluids STOP BLEEDING Tranexamic acid (stop bleeding)

Question 14

How should septic shock be managed?

Answer 14

Sepsis 6 3 in - o2, antibiotics (tazocin + gentamicin), fluids (20ml/kg crystalloid) 3 out - lactate, UO, blood cultures

Question 15

How should hypovolaemic shock be managed?

Answer 15

Treat underlying cause Give fluid bolus Raise LEGS

Question 16

What parameters does EWS look at?

Answer 16

Respiratory rate (shouldn’t be over 25 or below 8) Heart rate (shouldn’t be over 130) Systolic BP (shouldn’t be over 220 or below 90) Oxygen sats Temperature Level of consciousness (AVPU)

Question 17

What does a NEWS score of 1-4 mean?

Answer 17

Low clinical risk - monitor every 4 hours (as oppose to 12 hours if 0)

Question 18

What does a NEWS score of 5-6 mean?

Answer 18

Medium clinical risk - monitor every hour, escalate care

Question 19

What does a NEWS score of 7+ mean?

Answer 19

High clinical risk - continuous monitoring and escalated care, consider ICU

Question 20

What does level 2 care mean?

Answer 20

Single organ failure, usually requires HDU admission

Question 21

What does level 3 care mean?

Answer 21

Multiorgan failure, usually requires ICU admission

Question 22

What investigations should be done for someone with suspected haemorrhagic shock?

Answer 22

ABG, blood group and save, FBC, U&E

Question 23

What is the mechanism behind haemorrhage shock?

Answer 23

3 changes: - Baroreceptors detect change and increased HR, sympathetic nervous system and vasoconstriction - Adrenaline and steroids released - Reduced renal perfusion due to RAAS activation and water retention

Question 24

What is the definition of major haemorrhagic shock?

Answer 24

Loss of 70ml/kg in 34 hr (or 50% of blood volume in 3 hours)

Question 25

In severe blood loss, what are the things that can kill you?

Answer 25

Acidosis Hypothermia Coagulopathy Each one may lead to another, causing a downward spiral

Question 26

What are the 4 signs of brain herniation?

Answer 26

1. CN3 palsy (pupil dilation) 2. Motor posturing (decorticate - flexed) 3. Lower rigidity 4. Hyperventilation

Question 27

What are the 4 signs of raised ICP?

Answer 27

1. Decreased consciousness 2. Cushings response 3. Vomiting 4. CN 6 palsy

Question 28

What is Cushing’s response?

Answer 28

Triad of: 1. Increased BP 2. Decreased pulse 3. Slow, irregular respiration This indicates death within minutes to hours

Question 29

What should normal cerebral blood flow be?

Answer 29

750 millliletres per minute

Question 30

What should normal ICP be?

Answer 30

7-15 mmHg

Question 31

What investigations should be done for someone with suspected brain trauma?

Answer 31

Bedside - obs, ECG Bloods - oxygen, haemoglobin Imaging - CT, MRI Special - cerebral perfusion pressure

Question 32

What is a decompression craniectomy?

Answer 32

A surgical procedure to allow brain expansion if there is raised ICP