chapter 29 - Shock/hypotension Flashcards
what is a chronotropic effect
causes a change in HR
-can be positive or negative
what is a dromotropic effect
change in speed of electrical conduction
-can be positive or negative
what is an inotropic effect
change in myocardial contraction
what is normotensive
normal BP
what is a pressor
an effect that increases BP
homeostatic mechanisms
-autonomic resources
-capillary fluid shifts
-neurohormones
causes of hypotension
-failure for the heart to pump effectively -dysrhythmias and HF
- blood or fluid loss
-extreme stress that depletes NE
what is the impact of hypotension
-decreased o2 to tissues
-accumulation of waste products
-shock
-cell death
what is shock
compromised oxygen delivery, consumption, and utilization
-causes cellular and tissue hypoxia
treatment of shock/hypotension
increasing fluids
what is hypovolemic shock
decreased circulating volume
most common
-the result of hemorrhage, trauma, burns, diabetes insipidus (increased urine), or ketoacidosis (high sugar)
children can get from V/D
what is cardiogenic shock
pumping problem with the heart
-caused by MI, dysrhythmias, valve or ventricle rupture
what is obstructive shock
obstruction of flow
-caused by mass, accumulation of fluid, blood clot
what is distributive shock
massive vasodilation
anaphylactic: histamine release
neurogenic: spinal cord injury
septic: inflammatory response to infection
what happens during compensated shock
activation of SNS
-body attempts to restore homeostasis
-increases HR and vasoconstriction
what happens during uncompensated shock
normally body does not have enough blood volume to compensate
-progressive organ dysfunction
-CO/HR/BP continues to decrease
S: cool, clammy, restless, diaphoretic, decreased urine, metabolic acidosis
NEEDS RAPID MEDICAL ATTENTION
what happens during irreversible shock
permanent damage
-multi-organ failure, first is normally renal with no urine output
-pH imbalance, decreased CO and SEVERE hypotension
how do vasopressors work
potent vasoconstriction
side effects of vasopressors
decreased renal profusion, decreased liver profusion, dysrhythmias, ischemia of limbs, extravasation –needs to be given in central line due to toxicity
common vasopressor
norepinephrine
who can not have vasopressors
dysrhythmias, angina pectoris, hypertension, hyperthyroidism, cerebrovascular disease, and glaucoma, can also worsen psychiatric disorders
what does epinephrine do
stimulates beta and alpha receptors, causes vasoconstriction
what does dopamine do
potent alpha agonist
low dose: dilate renal and coronary arteries
high dose: increase HR and vasoconstriction
what does dobutamine do
stimulates beta 1, increased contractility
-does not cause tachycardia
-can not be run with bicarb