Sudden Death Flashcards
what are the four H’s that can cause cardiac arrest?
hypoxia
hypovolaemia
hyperkalaemia + other metabolic
hypothermia
what are the four T’s that can cause cardiac arrest?
thrombosis
tamponade
toxins
tension pneumothorax
what is the definition of shock?
a condition of inadequate perfusion to sustain normal organ function
what are the four main classes of shock?
hypovolaemic
cardiogenic
obstructive
distributive
what is hypovolaemic shock?
a state of shock due to insufficient circulating volume
what can cause hypovolaemic shock?
any loss of fluids
what does the clinical presentation of hypovolaemic shock depend on?
the degree of hypovolaemia
how the body is compensating
describe how young people with hypovolaemic shock compensate
initially very well
decompensate rapidly if fluid loss continues
what is cardiogenic shock?
a state of shock due to the heart being unable to pump to meet circulatory demands
what is the most common cause of cardiogenic shock?
acute MI
what is another possible cause of cardiogenic shock?
acute valve dysfunction e.g. acute mitral valve prolapse
clinical signs in cardiogenic shock are caused by what two things?
poor flow
backpressure
what clinical signs are present in cardiogenic shock due to poor flow?
hypotension
fatigue
syncope
what clinical signs are present in cardiogenic shock due to back pressure?
pulmonary oedema
elevated JVP
hepatic congestion
what is obstructive shock?
shock due to a physical obstruction to the heart or great vessels
what is the mechanism of shock in obstructive shock?
blockage affects cardiac filling and reduces the blood volume available
what are three possible causes of obstructive shock?
PE
cardiac tamponade
tension pneumothorax
what are other names for distributive shock?
vasodilatory shock
warm shock
what happens in distributive shock?
vessels dilate so there is not enough blood to maintain pressure and perfusion
what are the three subtypes of distributive shock?
septic
anaphylactic
neurogenic
what causes septic shock?
microbes release toxins that cause impaired vasoconstriction
what can be used to detect hypoperfusion in septic shock?
rising lactate levels
what drugs need to be given ASAP in septic shock?
antibiotics
vasopressors
what causes anaphylactic shock?
mast cells release vasodilators
what drug should be given in anaphylactic shock?
adrenaline
what can be measured to confirm diagnosis of anaphylactic shock?
serum try-tase
what causes neurogenic shock?
loss of sympathetic outflow due to a spinal injury
what is the mechanism of shock in neurogenic shock?
loss of sympathetics = vasodilation, hypotension and bradycardia
what drugs are given for neurogenic shock?
dopamine
vasopressors
what is clinical death?
the period of respiratory, cardiac and nervous system arrest when resuscitation can restore life