Shock
A syndrome in which tissue perfusion is inadequate for the tissues metabolic requirement
State the 5 different types of shock
- Hypovolaemic
- cardiogenic
- obstructive
- endocrine
- distributive
What causes Hypovolaemic shock
Loss of plasma or blood
What is the consequence of blood loss
Reduced systemic vascular resistance
What causes cardiogenic shock
Pump failure causes reduced cardiac output
What is the primary cause of cardiogenic shock
Ischaemia induced myocardial dysfunction
State other causes of cardiogenic shock (3)
- cardiomyopathy
- valve problems
- dysrhythmia
What causes distributive shock
Disruption of normal vascular autoregulation and profound vasodilation resulting in poor perfusion
When is distributive shock seen (4)
- anaphylaxis
- sepsis
- spinal chord injuries
- acute liver failure
What causes obstructive shock
Mechanical obstruction to normal cardiac output in an otherwise normal heart
Causes of obstructive shock (3)
- PE
- tamponade
- tension pneumothorax
Causes of endocrine shock (4)
- adrenal insufficiency
- hypothyroidism
- hyperthyroidism
- DKA
Neuroendocrine responses to shock (3)
- release of pituitary hormones
- release of cortisol
- release of glucagon
What causes myocardial dysfunction in shock (3)
- circulating cytokines with direct myocardial effect
- beta receptor downregulation
- decreased myocardiofilament calcium sensitivity
Common clinical feature of shock
Hypotension
Clinical presentation of cardiogenic shock
Signs of myocardial failure
Signs of septic shock (3)
- pyrexia
- vasodilation
- rapid capillary refill time
Signs of anaphylactic shock (4)
- profound vasodilation
- erythema
- bronchospasm
- oedema
Signs of hypovolaemia (3)
- pallor
- cold skin
- prolonged cap refill
Pharmacological management of shock
Adrenaline
