What is Shock?
a condition in which tissue perfusion is inadequate to deliver oxygen and nutrients to support vital organs and cellular function
when cells die what do they release?
lactic acid
stages of shock
compensatory
progressive
irreversible
compensatory stage of shock
SNS causes vasoconstriction, increased HR, and heart contractility perfusion of tissues is inadequate acidosis increased respiratory rate confusion
progressive stage of shock
BP and MAP decrease
all organs suffer hypoperfusion
vasoconstriction
decreased cerebral perfusion and hypoxia
irreversible stage of shock
organ damage is so severe that the pt does not respond to treatment and cannot survive
hypovolemic shock
inadequate circulating volvume
caused by sudden blood loss or severe dehydration and burns
management of hypovolemic shock
- restore circulating volume with crystalloids first
- blood products
- O2, monitor VS, labs, respiratory status, mentation and urine output
cardiogenic shock
loss of critical contractile function of the heart
assessment findings of cardiogenic shock
chest pain hypotension cool skin oliguiria decreased mentation dyspnea crackles elevated myocardial markers, BNP
management of cardiogenic shock
- increase myocardial O2 delivery, CO, decrease LV workload correct reversible problems fluids diuresis nitrates electrolyte repletion analgesia sedative monitor for dysrhythmias and hemodynamic status
circulatory shock
an acute failure of the circulatory system to supply the peripheral tissues and organs of the body with an adequate blood supply, resulting in cellular hypoxia
causes of circulatory shock
- damage of the heart from MI
- ineffective pumping caused by arrhythmias
- ventricular septal defect
- ventricular aneurysm
- acute disruption of valvular function
- problems with open heart sx
hypovolemic circulatory shock
- loss of whole blood
- loss of plasma
- loss of extracellular fluid
obstructive circulatory shock
- inability of heart to fill properly
- obstruction to outflow from the heart
distributive circulatory shock
- loss of sympathetic vasomotor tone
- presence of vasodilating substance in the blood
- presence of inflammatory mediators
complications of shock
- acute respiratory distress syndrome
- acute renal failure
-GI complication
DIC
MODS
types of crystalloids
- NA saline
- lactated ringers
- hypertonic solutions (3% saline)
types of colloids
albumin
dextran
what does dextran interfere with?
platelet aggregation
complication of fluid replacement
fluid overload
pulmonary edema
clinical manifestations of cardiogenic shock
- decrease CO
- CI
drug therapy for cardiogenic shock
NTG Nipride diuretics dobutamine amrinine digoxin dopamine IABP PTCA CABG
effects of NTG
- dilates coronary arteries, improves collateral blood flow to ischemic areas withing the heart
- reduces preload
- reduces LV afterload, which deacreased myocardial O2 demand and consumption
