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2018 VU Trauma > Shock > Flashcards

Flashcards in Shock Deck (41)
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1
Q

What ways can absolute fluid loss occur?

A
  • External haemorrhage
  • Internal haemorrhage
    o Concealed and revealed
     Concealed may come out mouth or anus
  • Plasma loss (burns)
  • Water and minerals
    o Dehydration
    o Diarrhoea and vomiting
    o Decreased fluid intake
    o Excessive diuresis
2
Q

What constitutes as a significant haemorrhage?

A
  • Adults – 1,000mls
  • Child – 500mls
  • Infant - 100 – 200mls
3
Q

What are signs and symptoms of a PT with absolute fluid loss or a significant haemorrhage?

A
  • Altered conscious state
    o Most likely later sign
  • Skin – pale, cool, clammy
  • Dizziness
  • Nausea +/- Vomiting
    o Consequence of vagal stimulation
  • Increase respirations
  • Increased Heart rate – rapid weak thread
  • BLOOD PRESSURE – Hypotension as a late sign
    o This will be maintained during the compensatory process as adults generally have extra blood vessels floating about.
4
Q

What is relative fluid loss?

A
  • Blood volume remains essentially the same, but the blood vessels capacity is increased due to vasodilation.
  • Plasma moves into the interstitial space due to increased permeability of vessel walls.
    o This can be seen in anaphylaxis
5
Q

What does relative fluid loss mean for the bodies blood volume?

A
  • It will remain essentially the same, but the ability of the cardiovascular system to maintain adequate perfusion pressure is adversely affected.
6
Q

What are causes of relative fluid loss?

A
-	Neural mediated causes
o	Syncope / fainting
o	Pain
o	Emotion
-	Sepsis
-	Anaphylaxis
-	Vasoactive drugs and substances 
o	For example, GTN, morphine
-	Spinal injury
7
Q

What are signs and symptoms of relative fluid loss?

A
  • Altered conscious state
  • Nausea, dizziness +/- vomiting
  • Skin; may be warm and flushed due to pooing in the periphery of pale and cool.
  • Tachypnoea
  • Tachycardia
  • Hypotension
    o Recent collapse or fainting
8
Q

What causes may impair oxygen transport?

A
  • Insufficient cardiac output
    o Myocardial hypoxia
     Form of hypoxia due to the myocardium being able to transport oxygen to the tissues
  • Low RBC count
    o Anaemic hypoxia
  • Low systemic vascular resistance and perfusion pressure
    o This is generally neuro mediated
9
Q

What are the results of impaired oxygen transport?

A
  • Anaerobic metabolism
  • Failure of sodium-potassium pumps
  • Acidosis
  • Sever tissue ischemia/tissue death
  • Death of the organism
10
Q

What are the mechanics of blood pressure?

A
  • Blood pressure is reliant upon two main factors, stroke volume and peripheral resistance.
11
Q

What occurs when BP drops ion the body?

A
  • The body initiates compensatory mechanisms
    o Increasing myocardial contractility (Cardiac output) also referred to as inotroping
    o Promote peripheral vasoconstriction
    o Tachycardia may accompany this increase myocardial contractility but they are not actively linked together.
12
Q

Define shock.

A
  • A continuing process defined by a chain of events leading to widespread reduction in tissue perfusion and subsequent impairment of cellular metabolism
  • Shock is a continuing process not a condition.
    o Shock will continue until interventions are initiated.
  • Shock may result from a variety of disease states and injuries. If the process involved in the condition are not stopped the patients will die.
13
Q

What is shock in terms related to body systems?

A
  • An inability of the cardiovascular system to adequately maintain perfusion
14
Q

What is perfusion mediated by?

A
  • Perfusion is mediated by the cardiovascular system which is reliant upon the following three mechanisms.
    o Heart as a pump
    o Vessels as a container both the arterial arteries and veins
    o Blood as it creates volume.
15
Q

What are the stages of shock if left untreated?

A
  • Compensation
  • Decompensation
  • Irreversible
16
Q

What factors determine how fast a PT will travel through the stages of shock?

A
  • It is highly dependent on what has caused it and what interventions are put in place.
17
Q

How is blood pressure determined?

A
  • Heart Rate X Stroke Volume = Cardiac Output X Peripheral Vascular Resistance = Blood Pressure
  • ↑ HR x SV = CO x PVR = BP
18
Q

What factors are altered for BP to be maintained in compensated shock?

A
  • When need to increase our cardiac output or peripheral vascular resistance to maintain blood pressure.
    o Heart Rate may be increased (cronotroping)
    o Stroke volume with definitely be increased (inotroping, increasing the force of contraction)
19
Q

What are you signs in symptoms in PT that is in a compensating state?

A
  • Tachycardia
  • Slightly Pale
  • BP will remain stable. However, you may see a slight rise in systolic BP as pulse pressure increases.
20
Q

What are some warning signs of the PT that is in the compensatory stage?

A
  • A reduced mental state/ agitation in this Pt is likely due to decreased cerebral perfusion.
  • The Pt stating that they feel as though they are going to die is highly likely that they are.
    o This statement lets us need to know what we have missed and act on it!
  • These Pt may be difficult to cannulate due to the peripheral vasoconstriction.
21
Q

What compensatory mechanisms are seen at the initial offset of shock?

A
  • Sympathetic response
  • Hormonal response
  • Adrenal response
22
Q

What is the max compensating HR?

A
  • 140 to 160 BPM
23
Q

In the decompensating PT what are we likely to see in regards to how our BP is obtained?

A
  • Heart Rate X Stroke Volume = Cardiac Output X Peripheral Vascular Resistance = Blood Pressure
  • ↑ HR x SV = CO x PVR = BP
    o Increased HR
    o Decreased SV
    o Decreased CO
    o Increased Peripheral Vascular Resistance
    o Decreased BP
24
Q

What is our Decompensating PT likely to present as?

A
  • Hypotension – pulse pressure redcued
  • Tachycardia
  • Tachypnoea
  • Pale and severely diaphoretic
  • Developing Altered conscious state (agitation/irritability)
  • Delayed Cap refill.
    o This will be a Pt with a cap refill of two seconds. A healthy pt has a cap refill of less than 2 seconds.
25
Q

Describe Irreversible Shock

A
  • Cellular ischemia and necrosis lead to release of contents into circulation
  • Acidosis worsens
  • Sludging of blood flow in capillary beds leads to formation of micro emboli
  • Cerebral hypoxia
    o This PT If they survive will have brain damage.
26
Q

What are signs and symptoms of irreversible shock?

A
  • The myocardium become hypoxic which has the potential to lead to the following.
    o Dysrhythmias and infarctions
  • Sympathetic response fails
    o In the short term this fail in sympathetic response leads to the following
     Unbated hypotension
    o In the long term this fail in sympathetic response leads to the following
     Disseminating intravascular coagulation, Adult raspatory distress syndrome and organ failure
27
Q

What are the PT presentation of irreversible shock?

A
-	Bradycardia 
o	If they have a HR
-	Life threatening dysrhythmias
-	Sever unabated hypotension
-	Abnormal respiratory patterns
o	Due to cerebral hypoxic effects on the respiratory drive
-	Alt conscious state – normally unconscious
-	Cyanosis and mottling of the skin
-	Death
28
Q

What factors may cause shock to process at different rates and stages?

A
  • Age
  • Paediatric patients do not have the ability to compensate as well
  • Pre- e existing disease, what condition is the PT in before this occurs?
  • The PT ability to activate compensatory mechanisms.
    o This becomes more challenging as the PT becomes older
  • Mediations
    o Beta blockers, Diuretics
  • Specific organs that are affected by trauma or disease
29
Q

What are the TYPES of Shock?

A
  • Cardiogenic
    o Occurs as a result of an inability of the heart to adequately to pump.
    o These Pts will generally skip compensatory phase as these mechanisms are compromised.
     For example, APO PT with hypotension
  • Neurogenic
    o Occurs as a result of reduced peripheral vascular resistance
     Compensatory are not activated as there is no sympathetic response
  • Anaphylactic
    o Caused by a severe allergic reaction
     This causes a relative fluid shift
    • And compensatory mechanisms fail due to the vasodilation
  • Septic
    o Occurs due to gross overwhelming infection
     Often seen in those with low immune systems or low mobility (OLD CUNTS)
    • The process of septic shock is as follows
    o Release of bacterial toxins
    o Vasodilation and permeability of vessel walls
    o Relative fluid loss
    o Cellular necrosis and inflammatory response interferes with compensatory mechanisms
  • Hypovolemic
    o Fluid loss may be absolute or relative
     Offset by compensatory methods initially
    o Loss of whole blood, plasma or interstitial fluid
    o Renal compensatory methods
30
Q

What are common causes of cardiogenic shock?

A
  • AMI
  • Tension pneumothorax
  • Cardiac tamponade
  • Pulmonary Embolism
  • Valvular disease
  • Cardiomyopathies
31
Q

What are management options in the setting of cardiogenic shock?

A
  • Reperfusion strategies
  • Possible circulatory support
    o Fluid replacement – MICA Only
  • Drug Therapy
    o Vasodilators to reduce afterload
    o Positive inotropes to increase Stroke Volume and contractility
    o Positive chronotropes to increase HR
32
Q

Why is systemic Inflammatory Response Syndrome (SIRS) important in regards to septic shock?

A
  • It is a key component due to the inflammatory response in this condition
33
Q

What is the PT presentation of Septic Shock?

A
  • Low arterial pressure
  • Low Systemic Vascular resistance
    o This is due to vasodilation
  • Tachycardia
  • Temperature instability
    o You can have hot or cold sepsis
     This depends on the type of injection and its impact on the temperature regulatory systems
  • Affected organ systems
    o Renal, resp and brain
34
Q

What is the treatment of septic shock?

A
  • Management of hypovolemia if present
  • Correction of metabolic acid-base imbalances
  • fluid resuscitation
  • Respiratory support
  • Vasopressors to improve cardiac output
  • Thorough history to identify the source of sepsis
35
Q

What are the causes of hypovolaemic shock/

A
  • Haemorrhage
  • Burns (plasma loss)
  • Dehydration
    o Through diarrhoea, vomiting, diuresis and diabetes
36
Q

How will a PT with hypovolaemic shock present?

A
  • Poor perfusion
  • Poor skin turgor
    o This shows significant fluid loss
  • Thirst
  • Oliguria
  • Need to elicit good history with these PT
37
Q

What are key factors that need to be recognised for positive PT outcome for severe haemorrhage or shock?

A
  • Rapid recognition
  • Early initiation of treatment
  • Prevention of additional injury
  • Rapid transport to appropriate hospital
  • Advance notification to receiving facility
38
Q

What is the best way to achieve fluid resuscitation

A
  • Blood transfusions are the most effective way, but fluids will buy time for the PT.
39
Q

What reasons do we administer fluid replalcement?

A
  • In volume depleted patients
  • To expand the fluid volume, for example, anaphylaxis
    o Must be careful once conditions has reversed not to place these PT into APO
  • As a fluid challenge in PEA/EMD
  • Vehicle for drug administration
  • TKVO
40
Q

What type of fluid solutions are available?

A
  • Isotonic solutions
    o Concentration of solutes are the same a s those in body fluids
  • Hypotonic solutions
    o Solution has a lower concentration of solutes than those of body fluids
  • Hypertonic solutions
    o Solution ha a higher concentration of solutes than those of body fluids
41
Q

What are the causes of aggressive fluid resuscitation?

A
  • Additional bleeding, clot dissolution and dilution of clotting factors
    o All this adds to increase in haemorrhage.