Shock Flashcards
what is shock?
insufficient delivery of oxygenated blood to the microcirculation resulting in tissue hypoxia and cellular dysfunction
What are the common factors among all types of shock?
hypoperfusion and impaired cellular oxygen utilization
What are the 4 types of shock?
- cardiogenic
- obstruction
- hypovolemic
- distributive
obstruction shock
circulatory blockage disrupts CO
Distributive shock
greatly expanded vascular space because of inappropriate vasodilation
cardiogenic shock
results from heart disorders that cause inadequate CO despite sufficient vascular volume
hypovolemic shock
associated with loss of blood volume
What can hypoxia lead to?
cell death, organ dysfunction, and stimulation of inflammatory rxns
What does lack of oxygen cause?
anaerobic metabolism
failure of ion pumps lead to salt and water reabsorption in cell swelling
formation oxygen radicals
induction of inflammatory cytokines
What are the early defects in shock?
displaying signs of insufficient CO and decreased tissue perfusion
Nurse K thinks John is in shock how does she know this?
john’s pulse pressure narrows, he is tachycardic, fast and deep respirations, decreased urinary output, increased urine specific gravity, cool/clammy skin, altered mentation and dilated pupils
What is progressive shock marked by?
hypotension and hypoxia
Nurse K actually detects John is in progressive shock how does she know this?
John has the following clinical manifestations: hypotension, narrow pulse pressure, tachycardia, acute renal failure, decreased level of consciousness, increased respiratory rates and metabolic and respiratory acidosis with hypoxemia
Diagnostic features of cardiogenic shock
decreased CO, pulmonary edema, elevated left ventricular end diastolic pressure (preload)
Therapy for cardiogenic shock
improving CO and myocardial workload
Common causes of Obstructive shock
pulmonary embolism, cardiac temponade, tension pnuemonthorax; manifested as right-sided heart failure
What are internal external losses of hypovolemic shock?
External: burns, external hemorrhage, severe vomiting, diarrhea, and diuresis
Internal: internal hemorrhage, fracture of long bones or leakage of fluid into the interstitial space
What is the treatment for hypovolemic shock?
therapy is aimed at fluid replacement and controlling the volume by colloids, crystalloids, and and blood
What do all types of distributive shock have in common?
vasodilation and profound hypotension
What are the types of distributive shock?
anaphylactic, septic, and neurogenic
Etiology of anaphylactic shock
IgE Ab binds to receptor releasing histamines,, leukotrienes, and prostagladins that cause bronchiconstriction, peripheral vasodilation and increase capillary permeability
Si/Sx of anaphylactic shock
hives, itching, hypotension, bronchiconstriction ( wheezing and cyanosis)
Treatment of anaphylactic shock
antihistamines, vasodilators, EP, and vasopressors
Neurogenic shock
loss of sympathetic activation of arteriolar smooth muscle
Causes of neurogenic shock
brain injury, drug overdose or spinal cord injury
Treatment of neurogenic shock
re-establish pooling, elevation of legs, fluids, slow position changes and use of stocking
septic shock
results from severe systemic inflammatory response to infection
What are the common causes of septic shock?
gram-negative and gram-positive bacteria
How is septic shock characterized?
release of immune mediators causing inflammations, profound peripheral vasodilation with hypotension, cellular hypoxia and edema
What are complications of shock?
generalized inflammatory response and may affect affect all organs and systems of the body
Acute Respiratory Distress Syndrome
most commonly associated with septic shock; pulmonary edema leads to pulmonary compliance; lungs are most affected
Disseminated Intravascular Coagulation
usually occurs in septic shock
Acute renal failure
kidneys undergo prolonged periods of hypoperfusion, kidneys do not respond to fluids or diuretics
