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19 Cards in this Set
- Front
- Back
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What is circulatory shock?
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Cardiovascular dysfunction associated with inadequate tissue perfusion of the vital organs, leading to collapse of homeostasis. CO is insufficient to meet peripheral metabolic needs.
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What are the 5 causes of circulatory shock?
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Hypovolemic
Septic Neurogenic Anaphylactic Cardiogenic |
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What are the effects of blood loss on MAP? At what point does it become decompensated?
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Initially, hemorrhage results in decrease in MAP that is compensated. Blood pressure is returned to normal within a few hours. At around 40% blood loss, the compensatory mechanisms fail.
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What is the initial response to hemorrhage?
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Decreased venous pressure, decreased EDV, decreased SV, decreased CO, decreased arterial pressure.
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What are the stages of shock?
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Compensated shock
Progressive shock Irreversible shock |
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What is the baroreflex response in compensated shock?
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Increased heart rate, cardiac contractility, arteriolar constriction and venous tone return CO toward normal.
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What is the sympathetic response in compensated shock?
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Decreased perfusion to nonessential organs.
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What is the hormonal compensation in compensated shock?
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Adrenal catecholamine release
RAAS activation to conserve water ADH release to conserve water Reduced ANP and BNP |
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How do the capillaries function in compensated shock?
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Capillary hypotension due to arteriolar constriction causes absorption of fluid.
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What is the result of increased absorption in the capillaries?
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Decreased plasma colloid osmotic pressure to the dilution of plasma proteins.
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What happens in decompensated shock?
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Cardiac depression
Decreased vasoconstriction Endothelial dysfunction Acidosis DIC CNS depression Reduced organ perfusion |
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What causes irreversible shock?
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Loss of energy reserves required to maintain cellular function.
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What are results of irreversible shock?
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Increased capillary permeability
Multiple organ failure Acute respiratory distress syndrome Nitic oxide overproduction Decreases in blood pressure |
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What are features of septic shock?
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Fever, vasodilation, initial hyperdynamic phase followed by hypodynamic stage.
Cardiovascular failure, DIC, ARDS, multiple organ failure |
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What can potentially cause septic shock?
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Peritonitis from uterus
Perforation of the gut Generalized infection Kidney or UTI Trauma/ burn |
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What is SIRS? What are the criteria?
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Systemic response to infection.
Temp >100.5 or <96.8 HR > 120bpm RR>20breaths/min Leukocytes >12000 |
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What is the most important treatment in shock? Why must it be watched closely?
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Fluids- increasing blood volume too much can cause edema and congestion due to overloading.
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How is ventricular filling pressure measured?
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Pulmonary capillary wedge pressure
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Why are vasoconstrictors used to treat circulatory shock? Why are vasodilators?
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Vasoconstrictors increase blood pressure, but can reduce tissue perfusion.
Vasodilators (dopamin, alpha 1 antagonist, beta agonist) are administered to relieve excess sympathetic constriction after cardiac output is elevated by fluids. |
