Shock Flashcards
(121 cards)
What is shock
- decreased tissue perfusion and impaired cellular metabolism
- tissue perfusion does not meet the cellular 02 requirements
- imbalance between supply and demand for 02 and nutrients
Shock is a problem with….
- pump: cariogenic
- volume: hypovolemic
- vessels: distributive and obstructive
TRUE OR FALSE: shock is defined by low blood
false
CO
SV X HR and is where perfusion comes from
CO is..
-amount of blood ejected by the heart in one minute (N= 4-8)
SV is …
-amount of blood ejected with each beat (N= 60-150)
SV is altered by…
- preload
- contractility
- afterload
how to assess preload
- weight
- I/O
- UO
- VS
- edema
- indicator of volume
How to assess afterload
- vasoconstriction (cold and clammy)
- vasodilation (red and sweating)
- BP
- Skin assessment
- peripheral pulse (weak or bounding?)
how to assess Contractility
- Echo
what happens to vitals when preload goes down
- increased HR and decreased BP
what is CO used to evaluate
- contractility but hard to pinpoint actual cause of low CO
Things that can affect CO
- decreased contractility from direct myocardial insult (from cardiogenic shock)
- inadequate myocardial stretch from preload being too low (from hypovolemic shock)
- overstretched myocardium from preload being too high
- low afterload (vasodilation from neurogenic or spetic shock)
- high afterload (vasoconstriction)
why do we use pressure as a measurement
- because its difficult to measure volume in the ventricles so we use pressure to estimate volume
- pressure indicates stretch and volume
what measures preload
- CVP
- PAWP
what measures afterload
-SVR/PVR
How is perfusion measured
-by MAP and BP
organ perfusion measures
- RN orders to titrate
- MAP > 65 OR greater (MAP > 60 needed to perfuse and sustain vital organs)
- SBP > 90 (kidneys wont produce urine below 60)
pulse pressure
- difference between systolic and diastolic
- provides info on what peripheral vessels are doing to maintain BP
- N= 40
- <40= vasoconstriction
- > 40= vasodilation
a narrowed pulse pressure and increased heart rate indicates
hypovolemia
types of shock
- Cardiogenic: pump failure
- Hypovolemic: decrease intravascular volume
- Distributive: misdistribution of circulating blood volume
- Neurogenic shock: loss of sympathetic tone
- Anaphylactic shock: massive hypersensitivity response
- Septic shock: overwhelming inflammatory response - Obstructive: physical blockage of blood flow
cardiogenic shock
- Pump failure
- Systolic or diastolic dysfunction→ decreased stroke volume→ reduced CO
causes of cardiogenic shock
- MI (systolic dysfunction)
- Cardiac tamponade or cardiomyopathy (diastolic)
- Structural issue (valvular disorder)
- Dysrhythmia
cardiogenic shock mani
- Similar to decompensated heart failure
- Tachycardia, hypotension, narrow pulse pressure
- ↑SVR
- Increase in pulmonary wedge pressure
- Tachypnea
- Crackles
- Signs of peripheral hypoperfusion (Cyanosis, pallor, diaphoresis, weak peripheral pulses, cold/clammy skin)
- ↓urine output
- Anxiety, confusion, agitation