Shock Flashcards
Define shock
State of organ hypoperfusion causing cellular damage and death due to lack of oxygen
True or false
Shock is a pathological state
True
True or false
Shock isn’t always an emergency
False
It is ALWAYS an emergency
What is the difference between emotional and pathological shock
Pathological shock is a physiological state of being
Emotional shock occurs after a distressing event
What are some basic causes of shock
Trauma
Dehydration
Blood loss
Lack of oxygen
What are the 3 major categories of the causes of shock
Hypovolemic shock
Cardiogenic shock
Distributive/vasogenic shock
What is hypovolemic shock
Most common
Occurs when there is a loss in blood/fluid volume which results in inadequate circulatory volume and hypotension which causes decreased perfusion
Or due to plasma volumes being lost through burns, dehydration, vomitting, diarrhea, or effusions
Define perfusion
The passing of fluid through vessels to a tissue or organ
Define effusion
The escape of fluid into a body cavity
What is hemorrhagic shock
Type of hypovolemic shock caused hy acute blood loss (trauma, surgery, bleeding disorders, DIC)
What is cardiogenic shock
When the heart is unable to pump there is a decreased cardiac output which causes hypotension and decreased perfusion
When does cardiogenic shock occur
With end stage congestive heart failure, arrythmias, myocardial infarcation, ventrical abnormalities, pericardial effusion, trauma
What is myocardial infarcation
Obstruction of the blood supply to the heart
What is vasogenic shock or distributive shock
Something causes the blood vessels to dilate which causes blood to pool in capillaries and decreases blood flow ti other organs or tissues
What are 4 of the many causes of vasogenic shock (and therefore vasodilation)
Anaphylactic shock
Endotoxic shock
Neurogenic shock
Septic shock
What is anaphylactic shock
A type of vasogenic shock caused by a secere allergic reaction that affects multiple organ systems
If enough histamine is released during reaction and enter circulation, it causes wide spread dilation of the capillaries
True or false
Vasodilation is always part of inflammation
True
How fast does anaphylactic shock occur
Minutes to hours
What is endotoxic shock
A type of vasogenic shock, it is systemic vasodilation that occurs due ti an underlying gram negative infection, the bacteria release large amounts of endotoxin (lipid A of lipopolysaccharides) which enters circulation and creates widespread inflammation/vasodilation
What is neurogenic shock
A type of vasogenic shock, occurs with trauma to the brain or soinal cord that disrupts the autonomic NS
What happens in neurogenic shock due to lack of sympathetic innervation
Causes a lack of vascular resistance (vasoconstriction) in the capillaries (especially in the GIT and skin)
Can causes slowing down of the heart (cardiogenic component)
What is septic shock
A type of vasogenic shock, caused by wide spread inflammation due to an underlying systemic bacterial infection (most common), fungus or virus. causing widespread inflammation
When is septic shock seen
Perforated GI foreign bodies
Neonatal foal spesis
And severe infections
What are some other causes of vasogenic/distributive shock not related to inflammation
Hyperthermia
Overdose with inhalant anesthetic
In human medicine, what is obstructive shock
Shock due to an obstruction of blood flow
True or false
You can be classified as having mutiple different types of shock at once
True
Give an example of the type of shock a hit by car patient would have
Hypovolemic (bleeding)
Distributive (damage to brain spinal cord)
Once shock has set in, what are the two levels of shock that occur
Compensatory shock
Non compensatory shock
What is compensatory shock
This is the Early stage of shock, in this stage is when the systems not affected/causing the shock will increase fucntion to try and offset the failing parts
If there is blood volume loss how does the body compensate
Increasing heart rate and constricting vessels
If the heart fails, how does the body compensate
Blood vessels constrict and the body will retain water
If the blood vessels dialte, how does the body compensate
The heart will be faster and try to retain water
Increased heart rate and vasoconstriction is driven by the
Sympathetic nervous system
Water retention and vasoconstriction are also driven by
The hormonal system based in the kidneys
In early stages of shock, there may be a normal or mildly affected blood pressure, normal CRT, pink to pale pink MM, normal temp, with an increased ____
Heart rate and respiratory rate
How long is the compensatory stage of shock
Very short
If the underlying cause of shock is not treated during the early stages of shock what happens
Patient will go into non compensatory shock
What is non compensatory shock
When the body cannot keep up or compensate enough to the causes of shock, at this point blood pressure will start/continue to drop
Blood flow shifts to vital organs and away from others causing ischemic damage which causes lactic acid production and acidosis, then myocardial disfunction and death
What are the initial signs of non compensatory shock
Drop in blood pressure
Increased HR and RR
CRT >2
Light pink to pale MM
What are the clinical signs of non-compensatory shock after it has advanced
Drop in blood pressure Decreased HR and RR temp drops (can feel in extremities and mouth) Weak pulse Coma/stupor Pale MM (cyanotic or muddy) Long CRT
Once acidosis develops in non compensatory shock due to decreased heart function, what occurs
Decreased blood flow and hypothermia this then leads to issues with clotting
There is rapid death at this point
Why is compensatory shock difficult to diagnose
It has a normal BP with an increasing HR and RR (must determine whether its shock based on history)
Temp is normal (may be high with inflammation)
CRT is normalish
What are the steps in treating shock
Place IV catheter and starte shock fluid rate
Stop bleeding
Give oxygen
Restore acid-base imbalances/correct electrolytes
Support organ function
Treat underlying problem
What are the shock fluid rates
90ml/kg for dogs
50ml/kg for cats
80ml/kg for large animal
What are the steps in giving shock fluid rates
Give the first 25% of the volume ASAP
assess vitals
If vitals are still low Give another 25%
If they are still low again, add a colloid
Go to regular fluid plan once they are stable
How long does it take for each fluid portion to stabilize the patient
Approx 20 minutes
What is the therapeutic objective in shock
To return blood pressure to normal to restore tissue perfusion
How do you support organ function in shock
Intestinal protectants
Heart medication
Vasoconstrictors
How may you treat underlying causes of shock
Antibiotics Surgery Anti-inflammatories Transfusions Anti-arrhythmia drugs Antihistamines
