A to E: Circulation - Shock

Question 1

Suggest four clinical features of circulatory failure

Answer 1

• Low (SBP <90 mmHg) or unobtainable BP
• Reduced GCS; altered mental state
• Cool peripheries; cyanosis; pale/mottled skin
  
  • Warm or flushed if distributive
• Tachycardia; tachypnoea; sweating
• Prolonged CRT (>2s)
• Weak peripheral and central pulses: rate; quality; rhythm
  
  • Bounding pulse may indicate sepsis
• Oligouria; anuria
• Evidence of haemorrhage

Question 2

Describe the different aetiological groups of shock

Answer 2

• Cardiogenic and obstructive shock
• Hypovolaemic shock
  
  • Haemorrhagic
  • Non-haemorrhagic
• Distributive shock
  
  • Septic
  • Anaphylactic
  • Neurogenic

Question 3

Define cardiogenic shock

Answer 3

Both (despite adequate LV filling pressure):

• Sustained hypotension: SBP <90 mmHg
• Tissue hypoperfusion, either:
  
  • Cold peripheries
  • Oligouria

Question 4

Name four causes of cardiogenic shock

Answer 4

Intrinsic heart problem:

• MI and its complications
• Arrhythmia
• HOCM
• Severe valvular disease

Other causes:

• Acute severe PE
• Obstructive: cardiac tamponade; constrictive pericarditis
• Tension pneumothorax
• Thyrotoxic crisis

Question 5

Name three causes of non-haemorrhagic hypovolaemic shock

Answer 5

• Inadequate intake:
  
  • Poor access to water
  • Neurological disability
• Excessive losses

Question 6

Differentiate between warm and cold shock

Answer 6

• Cold
  
  • Cardiogenic and obstructive shock
  • Hypovolaemia
• Warm
  
  • Distributive shock

Question 7

Request four investigations for suspected shock

Answer 7

• Obs: BP; RR; HR; temperature; urine output
• FBC
• U+Es
• LFTs
• Clotting; fibrinogen
• ECG
• CXR
• Echocardiogram

Question 8

Outline the basics of managing shock

Answer 8

• ABC assessment + frequent reassessment
• Supportive care:
  
  • Maintain temperature
  • High flow O₂
  • 1+ large-bore (14-16G) IV cannulae
  • Warmed fluid resuscitation
• Specific treatment as directed by underlying cause

Question 9

Outline the emergency management of acute coronary syndrome causing cardiogenic shock

Answer 9

• Immediate
  
  • Morphine IV
  • Oxygen: if hypoxic
  • Nitroglycerine: unless hypotensive
  • Aspirin 300mg
• 12-lead ECG
  
  • STEMI: PCI within 2hr; thrombolysis
  • NSTEMI/UA:
    
    • Aspirin + Clopidogrel
    • LMWH
    • B-blocker; GTN; ACEi; statin

Question 10

Outline the emergency management of pulmonary embolism causing cardiogenic and obstructive shock

Answer 10

• Wells’ score for PE
  
  • 4 or less (unlikely): d-dimer
  • >4 (likely): CTPA
• Haemodynamically unstable:
  
  • Continuous UFH infusion
  • Consider alteplase thrombolysis

Question 11

Outline the management of Addisonian crisis causing hypovolaemic shock

Answer 11

• Hydrocortisone 100mg IV/IM STAT
• 1L 0.9% NaCl over 30-60min
  
  • Add dextrose if hypoglycaemic
• Hydrocortisone infusion 6hrly till stable
  
  • Also exerts weak mineralocorticoid action

Question 12

Outline the initial management of septic shock

Answer 12

Shock is a red flag criteria of sepsis

Within 1hr:

• Give:
  
  • 500ml 0.9% NaCl STAT
  • Meropenam 1g IV
  • High flow O₂
• Take
  
  • Blood culture
  • Serum lactate
  • Urine output

Question 13

Outline the emergency management of anaphylatic shock in adults

Answer 13

• IM 0.5ml Adrenaline 1:1,000
  
  • Repeat every 5min as required
• 10mg Chlorphenamine
• 200mg slow IV Hydrocortisone