Shock Flashcards
What is shock?
When the circulatory system fails to carry out one of its essential functions
What happens when an organ is impaired so adequate blood flow can’t be achieved?
Blood flow to tissues are compromised and without treatment will lead to cellular death, organ failure and death
Name some causes of shock?
Haemorrhage, myocardial infarction, burns, anaphylaxis shock, infection and spinal injuries
What three components contribute to shock?
Reduction in circulation, failure of effective pump and lack of blood vessel
Name the four different types of shock?
Hypovolaemic - haemorrhage
Cardiogenic - myocardial infarction
Vascular - septic shock (infection)
Neurogenic - head injury
If arterial blood pressure is too low, what isn’t being formed?
Tissue fluid
Three important variables effecting blood pressure?
Cardiac output, peripheral resistance and blood volume
What is the stroke volume?
The amount of blood ejected from the left ventricle at each contraction
What is peripheral resistance?
The force created by the friction between blood and the walls of blood vessels
When identifying the signs and symptoms of someone in shock, what are the three things?
Look, feel and listen
Feedback loop of shock (homeostasis)?
Receptor: baroreceptors / chemoreceptors
Controller: hormones (ADH) / nervous system (vasomotor centre)
Effector: Smooth muscle / cardiac muscle / intercostal muscles
Responses: vasoconstriction, blood volume increase, HR increase, cardiac output increased, decreased urine output
Many systems are involved in trying to compensate for shock. If these fail to restore homeostasis, what happens?
Multiple organ system failure
In hypovolaemic shock, thirst will be stimulated by?
Angiotensin II
Reduced urine output in shock is due to?
Increased activity if the renin-angiotensin-aldosterone system and increased secretion of antidiuretic hormone
Cardiogenic shock is best described by?
The inability of the heart to act as an adequate pump
