module 10 shock

Question 1

shock

Answer 1

imbalance between O2 supply and demand at the cellular level : inadequate O2
- group of life threatening condition s
common factor: hypo-perfusion and impaired cellular oxygen utilization
could result from:
- dec. CO
- maldistribution of blood flow
- dec blood O2 content

Question 2

cardiogenic shock

Answer 2

inadequate CO despite sufficient vascular volume

blood pump problem

Question 3

obstructive shock

Answer 3

circulatory blockage
- large pulmonary embolus
- cardiac tamonade
disrupts CP 
blood flow problem

Question 4

hypovolemic shock

Answer 4

loss of blood volume as a result of hemorrhage or excessive loss of extracellular fluids
blood volume problem

Question 5

distributive shock

Answer 5

greatly expanded vascular space because of inappropriate vasodilation
- blood vessel problem

Question 6

common factor of shock

Answer 6

impaired O2 utilization by cells

• > dec. function, cell death, organ dysfunction, inflammatory reactions.
• > glycolysis to produce ATP -> lactic acidosis
  dec. ATP -> plasma membrane dysfunction
• > inc. intracellular Na and Ca -> swelling
• > free radical formation
• > inflammatory cytokines
• > cell death

Question 7

Hallmark of shock

Answer 7

failure of microcirculation to auto-regulate blood flow

-> abnml distribution of blood flow

Question 8

Shocks with hypotension

Answer 8

cardiogenic
obstructive
hypovolemic
distributive

Question 9

systemic vascular resistance and shocks

Answer 9

cardiogenic: high
obstructive: high
hypovolemic: high
distributive: low

Question 10

cardiac output and shocks

Answer 10

cardiogenic: low
obstructive: low
hypovolemic: low
distributive: high

Question 11

cardiac preload and shocks

Answer 11

cardiogenic: high
obstructive: low
hypovolemic: low
distributive: normal to low

Question 12

venous oxygen saturation and shocks

Answer 12

cardiogenic: low
obstructive: low
hypovolemic: low
distributive: high

Question 13

urine output and shocks

Answer 13

cardiogenic: low
obstructive: low
hypovolemic: low
distributive: low

Question 14

skin temperature and shocks

Answer 14

cardiogenic: cool
obstructive: cool
hypovolemic: cool
distributive: warm

Question 15

compensation

Answer 15

works in early stages

• especially hypovolemic shock
• cardiogenic: may worsen already high pre-load -> inc. workload
• distributive: vasculature non-responsive to SNS signals to constrict -> blood pooling in tissues

Question 16

s/s of early compensated shock

Answer 16

narrow pulse pressure, w/ or w/out hypotension
HR > 100
fast and deep resp
dec. urinary output
inc. urine specific gravity
cool clammy skin
altered mentation 
dilated pupils

Question 17

s/s of progressive stage

Answer 17

low BP, < 90
narrow pulse pressure
tachycardia
acute renal failure
- oliguria, inc. blood urea nitrogen and creatinine
dec. LOC
inc. resp. rate
metabolic and respiratory acidosis with hypoxemia

Question 18

cardiogenic shock primarily results from

Answer 18

dysfunction of one or both ventricles -> inadequate pumping
- MI
- end stage cardiomyopathy
- papillary muscle dysfunction
- free wall rupture
- congenital defects
inc. LV diastolic filling (preload)
- - differentiates cardiogenic from hypovolemic
-> pulmonary: fluid in tissue -> pulmonary edema
possible S3 heart sound

Question 19

causes of obstructive shock and s/s

Answer 19

mechanical obstruction that prevents effective cardiac filling and SV
common causes:
- pumonlary embolism
- cardiac tamponade
- tension pneumothorax
Manifests as RSHF
RV enlargement -> LV compression -> dec. CO

Question 20

obstructive shock and cardiac tamponade

Answer 20

pericardial sac has inc. fluid volume

• sac can only stretch so much, then pressure pushes on heart
• > compression of vena cava, atria, and pulmonary veins
• > RV collapse
• > dec. RV filling in diastole
• > dec. SV and CO
• > cardiac arrest

Question 21

causes of hypovolemic shock

Answer 21

hemorrhage
burns
dehydration 
- dec. intravascular vol. 
-> dec. preload
-> dec. CO
-> hypotension 
-> dec. tissue perfusion 
-> hypoxic cell injury 
-> progressive shock

Question 22

causes of distributive shock

Answer 22

abnormally expanded vascular space caused by excessive vasodilation -> polling of blood in venous capacitance vessels -> relative hypovolemia

• Types
• Anaphylactic: IgE mediated
• Neurogenic:
• – brain trauma
• – spinal cord injury
• – high spinal anesthesia
• – drug overdose
• Septic: gram-negative bacteria: endotoxin -> vasodilation

Question 23

neurogenic shock

Answer 23

type of distributive
imbalance between SNS and PSNS stimulation
- depression of vasomotor center in medulla
- interruption of sympathetic nerve fibers
- baroreceptor reflex not working
Massive vasodilation
-> dec. vascular tone
-> dec. SVR
-> dec. CO
-> dec. tissue perfusion
-> impaired cellular metabolism

Question 24

anaphylactic shock

Answer 24

type of distributive 
antigen (allergen) reaction with IgE
-> complement, histamine, kinins, and prostaglandin activation 
-> peripheral vasodilation, inc. capillary permeability
-> dec. SV, edema 
-> relative hypovolemia
-> dec. CO 
-> dec. tissue perfusion 
-> impaired cellular metabolism

Question 25

septic shock

Answer 25

type of distributive 
bacteremia
-gram-negative: endotoxin release 
-> proinflammatory cytokines 
-> activation of complement system, coag system, kinin system, and WBC's
-> release of anti-inflammatory cytokines
-> endothelial cell dysfunction 
-> cell damage and death
-> multiple organ dysfunction 
-> death

Question 26

high risk for septic shock

Answer 26

young and elderly
debilitated
malnourished
immunocompromised 
chronic health problems
invasive lines
catheters 
surgery