Shock Flashcards
1
Q
Define shock
A
an abnormality of the circulatory system, resulting in inadequate tissue perfusion and oxygenation
2
Q
Equation for mean arterial blood pressure
A
MAP = CO X SVR
3
Q
Define cardiac output
A
- the volume of blood pumped by each ventricle by the heart per minute
4
Q
Define Stroke Volume
A
- the volume of blood pumped by each ventricle by the heart per heart beat
5
Q
What 3 factors effect stroke volume?
A
- contraction of ventricle
- preload
- afterload
6
Q
Define preload
A
- how much blood is in ventricles before contraction
7
Q
Define afterload
A
- the pressure required to open the aortic valve
8
Q
Describe the flow of hypovolaemic shock
A
- -> loss of blood
- -> decreased blood volume
- -> decreased venous return
- -> decreased end diastolic volume
- -> decreased stroke volume
- -> decreased CO and BP
- -> Inadequate tissue perfusion
9
Q
Describe the flow of cardiogenic shock
A
- -> decreased cardiac contractility
- -> decreased stroke volume
- -> decreased cardiac output
- -> decreased BP
- -> Inadequate tissue perfusion
10
Q
What is cardiogenic shock?
A
- sustained hypotension by decreased cardiac contractility
11
Q
Describe the flow in a tension pneumothorax
A
- -> increased intrathoracic pressure
- -> decreased venous return
- -> decreased end diastolic volume
- -> decreased stroke volume
- -> decreased CO
- -> decreased BP
- -> Inadequate tissue perfusion
12
Q
Describe the flow in neurogenic shock
A
- -> loss of sympathetic tone
- -> massive venous and arterial vasodilation
- -> decreased venous return
- -> decreased heart rate
- -> decreased cardiac output
- -> inadequate tissue perfusion
13
Q
Treatment of shock
A
- High flow oxygen
- volume replacement
- intropes for cardiogenic shock
- ABCDE
14
Q
Define syncope
A
- transient loss in conciousness, defined by its rapid onset, short duration and almost complete recovery
15
Q
What are the 3 main categories of syncope?
A
- reflex syncope
- cardiac syncope
- orthostatic hypotension
16
Q
What are the 3 subcatergories of reflex syncopes?
A
- vasovagal
- carotid sinus
- situational
17
Q
Explain a vasovagal
A
- most common
- trigger e.g. blood or emotion
18
Q
Explain a carotid sinus syncope
A
- any manipulation to the neck or head
- tends to be in the elderly
19
Q
Explain a situational syncope
A
- immediately after a specific trigger e.g. cough
20
Q
Explain a cardiac syncope
A
- caused by a cardiac event, resulting in a sudden drop in cardiac outtput
- may be during excretion
