C13. Cardiovascular responses to shock Flashcards
what is tissue perfusion
Tissue perfusion refers to the flow of blood through the body’s tissues, delivering oxygen and nutrients while removing waste products.
what is shock
Abnormality of circulatory system resulting in inadequate tissue perfusion and oxygenation
why is it important to spot shock
people can die from shock and early recognition and intervention helps make a difference
shock > inadequate tissue perfusion >…..
inadequate tissue oxygenation> anerobic metabolism > accumulation of waste products > Cellular failure
What can cause inadequate tissue perfusion?
▪ Loss of blood volume
▪ Sudden severe impairment of heart function
▪ Physical obstruction to circulation
▪ Excessive vasodilation and abnormal distribution of blood flow
name 4 types of shock (relevant for this block)
Hypovolaemic shock
Cardiogenic shock
Obstructive shock
Distributive shock
what is hypovolaemic shock
loss of blood volume
name the 2 types of hypovolaemic shock
haemorrhagic and non-haemorrhagic
what can cause Haemorrhagic hypovolemic shock
trauma, GI bleed, ruptured aneurysm
what can cause Non-Haemorrhagic hypovolemic shock
Burns, GI losses, diabetic ketoacidosis
what is cardiogenic shock
sustained hypotension due to reduced cardiac function
name 4 examples of issues that can cause cardiogenic shock
contractility
mechanical
arrhythmia
cardiotoxicity
cardiogenic shock - contractility examples
(MI, myocarditis, cardiomyopathy)
cardiogenic shock - mechanical examples
Papillary muscle rupture
severe aortic stenosis
cardiogenic shock - arrhythmia examples
Heart block, VT, SVT, AF
cardiogenic shock - cardiotoxicity examples
medication overdose
what is obstructive shock
physical obstruction of flow outside of the heart
what conditions are due to obstructive shock - outflow
massive PE, cardiac tamponade, tension pneumothorax
what conditions are due to obstructive shock - venous return
vena cava syndrome
sickle cell splenic sequestration
what is distributive shock
abnormal distribution of blood flow
what are the 2 types of distributive shock
neurogenic
vasoactive
give an example for neurogenic and vasoactive distributive shock
Neurogenic - spinal cord injury
Vasoactive - sepsis
what is the management of Shock
- Call for help
- Structured approach <C>ABCDE</C>
- High flow oxygen to keep oxygen sats >94%
- iv access
- Fluid resuscitation (most)
- Specific treatments depending on cause
In hypovolemic (haemorrhagic) shock, compensatory mechanisms can maintain blood pressure until about >…% of blood volume is lost
> 30%
what does the body do to compensate blood loss and what side effects happen
increase pulse rate and resp rate=
aka increased HR via baroreceptor reflex
side effects of blood loss -
decreased MAP, SV, CO
blood pressure decrease
pulse pressure decrease
urine output decreases
become more anxious and confused
