Shock Flashcards
What is shock defined as?
inability of the circulatory system to meet the oxygen and nutrient needs of body tissues
Fill in the blank:
The cause for shock is; ___________ __________ does not meet _________ _________.
Tissue 02 supply does not meet 02 demand
what is the conceptual framework of shock?
relationship between 02 supply (delivery) and 02 demand (consumption)
What state is the body in during shock?
hypermetabolic; the body is using a lot of energy
What does the hypermetabolic state of shock cause?
skewed electrolytes
elevated blood glucose
pale and cool skin
decreased capillary refill
what is shock?
a condition in which tissue perfusion is inadequate to deliver oxygen and nutrients to support vital organs and cellular function
which body systems does shock effect?
ALL OF THEM
Shock effects all body systems
What are some potential causes for shock?
- Ineffective pumping
- insufficient volume
- massive vasodilation vascular bed
Physiological changes regarding shock?
- hypoperfusion of tissues
- hypermetabolism
- activation of inflammatory response
What is a sign the inflammatory response has been activated?
An elevated CRP is the main sign
CRP worsens the metabolic state because it requires steroids to treat; then worsens the hypermetabolic state causing the BG, and electrolytes to be elevated
requires an insulin drip to regulate BG
What is common to all shock states:
A. BP of 90mmHg, HR >100
B. Loss of blood volume
C. Decreased 02 delivery with decreased 02 consumption
D. Inadequate 02 delivery to meet cellular demands
The answer is d.
this is the biggest defining trait between all types of shock
With hypermetabolic, you will have increased oxygen consumption
What is the pathophysiology of shock? (4)
- diminished tissue perfusion
- widespread vasodilation
- cellular dysfunction
- compensatory mechanisms
- multiple organ dysfunction syndromes (MODS)
some major traits related to the pathophysiology of shock? (6)
- inadequate 02 to cells
- anaerobic metabolism
- acidotic environment
- Na-K pump malfunction
- cell structures damaged
- cell death
How long does it take MODS to reverse?
THIS IS A TRICK QUESTION
MODS IS NON REVERSIBLE BECAUSE TISSUE DEATH IS NON REVERSIBLE
tests to identify that compensatory mechanisms have begun working? (2)
ABG’s
Lactic Acid
How much of a window do we have for treating shock?
think time=muscle!!!
very narrow window for treatment of shock
signs of shock?
increased temperature increased HR low BP dizzy, cool and pale skin decreased UOP, and perfusion
What are the cellular effects of shock? (7)
- cellular edema
- Efflux of K+
- Increased membrane permeability
- lysosomal membrane rupture
- influx of Na and H20
- cell damage and death
- mitochondrial damage and swelling
What are cytokines?
any number of substances, such as interferon, interleukin, and growth factors, that are secreted by certain cells of the immune system and have an effect on other cells
What is perfusion dependant on?
MAP
What is the compensatory mechanism related to cytokines?
Cytokines are released by the cells and stimulate vasodilation or vasoconstriction depending on the need for cell oxygen and nutrients
What works together on the cellular level to increase CO?
interaction of neural, chemical, and hormonal regulators work together to adjust cardiac output and peripheral resistance
what is cardiogenic shock?
the heart is unable to pump enough blood to meet the needs of the body
Common causes of cardiogenic shock?
- Left ventricular failure
- Myocardial Infarction
- any condition stressing the myocardium (maybe coronary or noncoronary)
What is hypovolemic shock?
inadequate volume in the vascular space
Causes of hypovolemic shock?
- Blood Loss
- Third Spacing (fluid in extremities)
- Trauma
What population are most susceptible to hypovolemic shock?
The elderly
What is distributive shock?
abnormal placement or distribution of volume
Types of distributive shock?
- Sepsis
- Neurogenic
- Anaphylaxis
what two conditions does hypovolemic shock result from?
- decreased fluid volume in circulation (traumatic blood loss)
- Internal fluid shift (dehydration, severe edema, ascites)
Pathophysiology of hypovolemic shock?
decreased intravascular volume leads to decreased venous return to right atrium, decreases ventricular filling decreases cardiac output
decreased BP leads to decreased tissue perfusion which causes cell death
Examples of fluid shifts causing hypovolemic shock? (5)
- hemorrhage
- burns
- ascites
- Peritonitis
- dehydration
Why do burns cause fluid shifts resulting in hypovolemic shock?
third spacing results from the skins inability to keep fluids in; this is why burn patients need drains
Examples of fluid losses resulting in hypovolemic shock?? (6)
- trauma
- surgery
- vomiting
- diarrhea
- diuresis
- diabetes insipidus
why is it a problem when there is a diminished supply of hemoglobin?
Hemoglobin carries oxygen to tissues; with less hemoglobin comes less oxygen transported to tissues
What can a transport shock state lead to? (3)
- carbon monoxide toxicity
- anemia
- hemorrage
what might carbon monoxide toxicity look like?
cannot regulate; patient will be sleepy, confused, HA, stewed 02 and H and H
Pathophysiology of cariogenic shock?
impaired delivery due to cardiac dysfunction either by the right or left ventricle
causes of cardiogenic shock? (9)
- MI (especially anterior wall MI)
- mechanical complications (valve failure)
- cardiomyopathy (contractility)
- myocardial contusion (damage to heart)
- pericardial tamponade (fluid surrounding the heart, causing the heart to pump ineffectively)
- ventricular rupture
- arrhythmias
- valvular dysfunction (leaky valves)
- end stage HF
What is the number one cause of cardiogenic shock?
Anterior wall MI
Vulnerable populations for cardiogenic shock? (4)
- elderly
- diabetic
- anterior MI
- history of MI
pathophysiology of cardiogenic shock state?
decreased cardiac contractility
decreased stroke volume and CO
causes pulmonary congestion, decreased systemic tissue perfusion, and decreased coronary artery perfusion
how does necrosis effect the heart muscle?
impairs contractility and CO
cannot go back once the tissue is dead
effects of Infarction in LV? (6)
- necrosis in heart
- oxygenated blood not moved forward into systemic circulation
- tissues have decreased 02
- decreased SV
- decreased CO
- decreased BP
effects of infarction in RV? (5)
- ejects too little blood into the LV
- tissues have decreased 02
- decreased SV of LV
- decreased CO
- decreased BP
what is an obstructive shock state?
mechanical barrier to blood flow blocks 02 delivery to tissues
examples of obstructive shock causes? (3)
- pulmonary embolism
- tension pneumothorax
- cardiac tamponade
true or false:
You can only have one type of shock at a time
FALSE!
you can have more than one type of shock
characteristics of distributive (circulatory) shock?
- blood volume pools in peripheral vessels
- result of either loss of sympathetic tone or release of biochemical mediators from cells
- massive arterial and venous dilation cause peripheral pooling
3 types of distributive shock?
- septic
- neurogenic
- anaphylactic
what is septic shock caused by?
widespread infection
s/s r/t septic shock
- tachycardia, fever, flushed skin, bounding pulses, tachypnea, change in UOP, and GI function
what are two signs of hyper-metabolism?
increased blood sugar and insulin resistance
what does a high CRP indicate?
infection and the presence of long term diseases
what does CRP show?
inflammation in the body
treatment for CRP?
steroids: solumedrol prednisone cortisone dexamethasone
what is neurogenic shock?
loss of balance between sympathetic and parasympathetic
sympathetic nervous system unable to respond to body stressors
predominant parasympathetic response resulting vasodilation
causes of neurogenic shock? (5)
- spinal cord injury
- spinal anesthesia
- nervous system damage
- depressant action of a medication
- hypoglycemic
s/s of neurogenic shock?
dry and warm skin
hypotension
bradycardia
What is anaphylactic shock?
- severe allergic reaction with systemic antigen-antibody reaction
- sudden onset of HoTN, near compromise, respiratory distress and cardiac arrest
what type of cells release potent vasoactive substances in anaphylactic shock?
mast cells release histamine and bradykinin
what does anaphylactic shock cause throughout the body?
widespread vasodilation and capillary permeability
What occurs in the initial stage of shock?
no signs or symptoms yet
what occurs in the compensatory stage of shock?
attempt to compensate for decreased CO and adequate oxygen and nutrients – neural, hormonal and chemical responses
what occurs in the progressive stage of shock?
end organ failure due to cellular damage, usually GI and renal first then cardiac, with loss liver and cerebral function
What occurs in the refractory stage of shock?
irreversible damage (necrosis, tissue death)
What does the SNS cause in the compensatory stage of shock?
vasoconstriction
- increased HR and contractility
Maintains BP and CO
body shunts blood from skin, kidneys, and GI tract
- causing cool and clammy skin; hypoactive bowel sounds and decreased UOP, and perfusion of tissues is inadequate
what occurs in the compensatory stage of shock as a result of anaerobic metabolism?
acidosis
what increases r/t acidosis and what can it cause?
RR; may cause a compensatory respiratory alkalosis
