PMS: SHOCK Flashcards

hypovolemic shock
Terms Definitions
Shock from any  cause can progress to....
organ failure
What is multiple organ dysfunction syndrome?
often involves the ultimate failure of 2 or more organ systems after a severe illness or injury.
How can shock be classified? (3)
prinicipal pathophys process
clinical manifestations
What causes the following:

neurogenic or vasogenic: 
traumatic shock: 
cardiogenic: caused by heart failure
neurogenic or vasogenic: caused by alterations in vascular smooth muscle tone
anaphylactic: caused by hypersensitivity
septic: caused by infection
hypovolemic: caused by insufficient intravascular fluid volume
traumatic shock: components of hypovolemic and septic shock
What are common signs of symptoms of pt experiencing shock?
feel sick
What is the common pathway in all types of shock?
impairment of cellular metabolism
Explain the impairment of oxygen use in:
cardiogenic shock
hypovolemic shock
neurogenic, anaphylactic and septic shock
cardiogenic shock: CO is too low to deliver adequate oxygen to the cell
hypovolemic shock: O2 delivery is impaired by inadequate numbers of red cells or inadeq volume of intrvascular fluid.
Neurogenic, anaphylactic, septic shock: systemic vascular resistance is too low and perfusion pressure in the capillaries is inadequate to drive O2 across cell membranes
Septic shock: hypoxia is made worse by fever, which increases the cell's oxygen consumption rate and by endotoxic and inflammatory chemical disruption of cell metabolism, which impairs the cells' ability to use oxygen
What happens when a cell doesn't have oxygen?
it shifts from aerobic to anaerobic metabolism
anaerobic metabolism is less efficient method of extracting energy from carbon bonds and cell begins to use adenosine triphosphate faster than it can be replaced
What happens when a cell doesn't have ATP?
without ATP, cell loses its ability to maintain an electrochemical gradient across its selectively permeable membrane (ie. can't work the Na/K pump)
What happens if the Na and K pump doesn't work bc of lack of O2?
sodium and chloride builds up in the cell and K exits
How do you get decreased circulatory volume when there is impairment of oxygen use?
As sodium moves into the cell, water follows. Throughout the body, the water drawn from the interstitium into the cells is "replaced" by water that is in turn drawn out of the vascular space, often called "third spacing" of fluid
What 3 positive feedback loops further impair oxygen use:
1. activation of the clotting cascade
2. decreased circulatory volume
3. lysosomal enzyme release
What activates the clotting cascade in the positive feedback loop?
What are complications of clotting cascade in shock?
sluggish capillary flow decreases tissue perfusion further and activates the clotting cascade.
Complications: acute tubular necrosis, ARDS, DIC
What amplifies intravascular fluid loss?
when serum protein and other plasma proteins are consumed for fuel which results in decreased intravascular osmotic pressure, shift of fluid to the interstitial or extracellular spaces and decreased circulation volume
Impair oxygen use causes lysosomal enzymes to be released from cells...what is the impact?
the enzymes not only damage the cell that released them but also injures adjacent cells.
By damaging the mechanisms of surrounding cells, lysosomal enzymes extend areas of impaired metabolism and cellular injury.
WHen you don't have oxygen for cells, the cells go into anaerobic metabolism. This has an effect on the pH. Explain.
it causes metabolic acidosis
cardiac and skeletal muscle use lactic acid as fuel sources, but only for a limited time
What are consequences of decreasing pH of a cell?
Enzymes necessary for cellular function dissociate under acid conditions.
Enzyme dissociation stops cell function, repair and division.
As lactic acid is released systemically- blood pH drops, reducing the oxygen-carrying capacity of the blood; THEREFORE LESS OXYGEN IS DELIVERED TO THE CELLS!
further acidosis triggers the release of more lysosomal enzymes because the low pH disrupts lysosomal membrane integrity
What prevents glucose uptake?
vasoactive toxins, endotoxins, histamine and kinins
What can influence glucose metabolism to be increased or disrupted? (2)
fever or bacteria
What are the effects of high serum levels of cortisol, growth hormone, and catecholmines?
cause hyperglycemia and insulin resistance
increased SVR
increased cardiac contractility
When cells are not getting the glucose that they need, for example, due to a shock state- how do they compensate?
glycogenolysis, gluconeogenesis and lipolysis
True or False:
The depletion of fat and glycogen stores is the cause of organ failure.
The energy costs of glycogenolysis and lipolysis are considerable and contribute to the cells' failure.
What is a cause of organ failure in shock?
depletion of protein is a cause
why? Gluconeogensis causes proteins to be used for fuel soo these proteins are no longer available to maintain cellular structure, function, repair and replication.
During anaeorobic metabolism,
protein breakdown liberates ____, which is converted to ___ acid. IN sepsis this ____ acid is changed into lactic acid and positive feedback loop is formed.
During anaeorobic metabolism,
protein breakdown liberates alanine, which is converted to pyruvic acid. IN sepsis this pyruvic acid is changed into lactic acid and positive feedback loop is formed.
what is the byproduct of proteins broken down during anaerobic metabolism--aka what is produced?
urea and ammonia
In septic shock plasma protein breakdown includes ____, thereby impairing immune system function when it is most needed.
what is considered a final outcome of impaired cellular metabolism?
build up of metabolic end products in the cell and interstitial spaces. 
Waste products are toxic to the cells and further disrupt cellular function and membrane integrity.
Ex. in septic shock- a deficiency isn cellular metabolism and the buildup of toxins may precede and cause decreased tissue perfusion.
The inability of the heart of pump adequate blood to tissues and end organs from any cause, the most common being within hours of an acute MI or severe epidsode of myocardial ischemia.
What is this called?
cardiogenic shock
Name 3 things that can lead to cardiogenic shock.
 pathologic conditions that:
1. reduce contractility: AMI, cardiomyopathy, sepsis,  myocarditis, dysarrythmias, metabolic abnormalities, papillary muscle reputure
2. impair diastrolic filling: related to arrythmias
3. cause obstruction: due to PE, cardiac tamponade, valvular disorders and wall rupture or defects
What are some compensatory mechanisms that kick in when CO decreases?
RAA system
neurohormoanal and sympathetic nervous system
BP mainted through vasoconstriction in response to catecholmine release from adrenals; catecholmines also increase HR and contractility
Increases in blood volume and vascular resistance normalize blood pressure and increase cardiac performance
What progressively deteriorates the mycocardium?
increased coronary, tissue and cellular ischemia
pg. 1700
low measured CO
hallmarks of cardiogenic shock
What are signs of end organ failure in cardiogenic shock?
cyanosis, skin mottling, rapid, faint or irregular pulses, low urine output and occasional peripheral edema 
Name causes of hypovolemic shock.
whole blood (hemorrhage)
plasma (burns)
interstitial fluid (diaphoresis, DM, diabetes insipidus, emesis or diuresis)
How do the liver and spleen try to assist in hypovolemic shock?
add to blood volume by disgorging stored red blood cells and plasma
How do the kidneys assist in hypovolemic shock?
renin stimulates aldosterone relase and retention of sodium (and hence water), whereas ADH, or vasopressin, from the posterior pituitary gland increases water retention
high SVR
poor skin turgor
low systemic and pulmonary preloads and rapid heart rate
hypovolemic shock
Widespread and massive vasodilation that results from an imbalance between parasympathetic and sympathetic stimulation of vascular smooth muscle.
what is this describing?
neurogenic or vasogenic shock
Explain the process of impaired cellular metabolism as it related to neurogenic shock
blood volume has not changed, but the amt of space containing the blood has increased, so the SVR decreases drastically; thus pressure in the vessels is inadequate to drive nutrients across capillary membranes, and nutrient delivery to the cells is impaired.
parasympathetic stimulation automatically ___ sympathetic activity and vice versa
Normally, sympathetic stimulation maintain ____.
If the stimulation is interrupted or inhibited- this causes...
muscle tone
causes vasodilation
WHat are ways to interrupt sympathetic activity causing neurogenic shock?
trauma to the spinal cord or medulla
conditions that interrupt the supply of oxygen to the medulla, or conditions that deprive the medulla of glucose
Other: depressive drugs, anesthetic agents, severe emotional stress and pain
low SVR
ejection fraction remains high (indicates healthy myocardium)
neurogenic shock
True or False
Most  episodes of fainting are NOT shock
widespread hypersensitivity reaction
anaphylactic shock
What is the inflammatory response to allergen in anaphylactic shock?
vasodilation and increased vascular permeability, resulting in peripheral pooling and tissue edema
Extravascular effects: constriction of extravascular smooth muscle--often causes respiratory difficulty bc it tends to affect smooth muscle layers in the airways walls
What is often the first manifestation of anaphylactic shock?
anxiety, difficulty in breathing, GI cramps, edema, hives, and sensations of burning or iteching of the skin
Why do you give EPI in anaphylactic shock?
decrease mast cell and basophil degranulation, cause vasoconstriction and reverse airway constriction
How does septic shock happen? (ie progression)
begins with systemic inflammation response syndrome (SIRS)


severe sepsis

septic shock
What are the most common infection sites associated with sepsis in the ICU?
intravascular catheter
surgical wound infection
What is the leading cause of sepsis?
gram pos bacteria
(used to be gram neg but abx have helped lower)
How does bacteria enter the blood to form bacteremia?
1. directly from the stie of infection
2. from toxic substances released by the bacteria directly into the blood stream
What are the toxic substances released that lead to septic shock?
gram neg: endotoxins
gram pos: lipoteichoic acids and peptidoglycan
What are the proinflammatory cells released during septic shock?
what are proinflammatory mediators?
polymorphonuclear leukocytes
pg. 1704
Proinflammatory cytokines enhance tissue factors which initiates ______.
What is the end result of septic shock?
mixed antagonistic response syndrome as proinflammatory and anti-flammatory mediators respond, intensify and lead the host into MODS
Septic shock and states of proglonged shock cause.....
tissue hypoxia with lactic acidosis increase NO synthesis, activate ATP sensitive and calcium regulated K channels in vascular smoothmuscle and lead to depletion of ADH.
tachycardia causes cardiac output to remain normal or become elevated, although myocardial contractility is reduced.
Pt could be hyperthermic or hypothermic
What can help prevent evolution of severe sepsis and shock?
ABX and identifiying sepsis in early stages
What should be included in initial resuscitation in septic shock?
initial resuscitation within the first 6 hrs to include fluids, (crystalloids or colloids)
What are the most common causes of multiple organ dysfunction syndrome?
sepsis and septic shock
Who is at the greatest risk for developing MODS?
older adults and persons with significant tissue injury or preexisting disease
What causes secondary MODS?
the result of an excessive inflammatory reaction, after a latent period following the initial injury, in organs distant from the site of the original injury
What organs are most severely affected by MODS?
lungs, splanchnic bed, liver and kidneys
What is an early indicator of progression of sepsis to MODS?
shunting caused by loss of autoregulation in some organs
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