3 components of perfusion triangle
pump (heart)
container (blood vessels)
content (blood)
6 types of shock
hypovolaemic
cardiogenic
obstructive
distributive:
septic
anaphylactic
neurogenic
4 stages of shock
causes of hypovolaemic shock
clinical presentation of hypovolaemic shock
treatment for hypovolaemic shock
points to consider with blood loss
what is hypovolaemic shock
low volume of blood/fluid in circulation
what is obstructive shock
mechanical interference, problem with venous return, a physical obstruction to the flow of blood
causes of obstructive shock
Tension pneumothorax (trauma to parietal pleura, air from atmosphere enters pleural cavity, interpleural pressure increases, prevents inspiration + pushes mediastinum/trachea to contralateral side, mediastinum shift compresses the heart)
Aortic dissection (a tear within the aorta causing the inner + middle layers of the aorta to split)
Pericardial tamponade (fluid build up on pericardium, constricts filling of chambers)
Pulmonary embolism (restricted blood flow, stroke volume decreases, cardiac output decreases, hypotension, hypoxemic hypoxia (low level of 02 in blood), ischaemic, organ failure)
treatment of obstructive shock
Treat the cause
- Tension pneumothorax - needle decompression (equalise pressures of pleural cavity) - Pericardial Tamponade - pericardiocentesis (remove build up of fluid in the pericardium) - Pulmonary Embolism - heparin (anti-coagulants), thrombolytic drugs (streptokase), embolectomy - Aortic Dissection - Surgery
Treat the symptoms - oxygen therapy, fluids, vasopressors (adrenaline)
clinical presentation of obstructive shock
- Muffled/distant heart sounds
what is distributive shock
a group of 3 shocks that denotes vessel malfunction, resulting in a decrease in systemic vascular resistance
what is anaphylactic shock
severe allergic reaction, cytokine storm
what is septic shock
result of severe bacterial infection (anaphylaxis), releases toxins that causes vessels to become leaky + semi permeable
what is neurogenic shock
a loss of sympathetic vasomotor tone, due to inhibitions with neurotransmitters
describe the generalised process (result) of all types of shock
(9 stages)
systemic vasodilation hypotension low BP inadequate tissue perfusion generalised/localised hypoxia ischaemia necrosis organ failure death
causes of anaphylactic shock
Extreme sensitivity to a substance, binds to mast cells, degranulation of mast cells, mass release of chemical mediators (primarily histamines)
causes of septic shock
result of severe bacterial infection (anaphylaxis), releases toxins that causes increased vascular permeability
treatment of anaphylactic shock
clinical presentation of septic shock
Focus on patient history taking, active antibiotic course? Infection management not working?, is the patient vulnerable
- Mottled skin - Fever (remember cold sepsis) - Portsmouth sign (when SBP falls below HR) - heart is in overdrive but cardiac output is insufficient - Confusion (especially in elderly, lack of blood supply to the brain)
treatment of septic shock
causes of neurogenic shock
- Regional analgesia
clinical presentation of neurogenic shock
Autonomic blockade, causes unopposed vagal tone, bradycardia
Essentially nerves are unable to communicate with the body, specifically the cardiovascular system, inhibits vasoconstriction + cardiac contractility, causes vasodilation, low BP, low SVR, inadequate tissue perfusion, ischaemia, necrosis, organ failure