Shock
Anna D. Jarvis
Introduction
Shock is a syndrome characterized by inadequate supply of oxygen and nutrients to meet tissue needs
Causes: hypovolemic, distributive, obstructive, cardiogenic, and dissociative
Also classified as compensated, decompensated, and irreversible shock
Shock is a continuum of vital organ dysfunction, from a single system problem (e.g., hemorrhage) progressing to secondary organ damage leading to multisystem failure and eventually death
(e.g., hemorrhage → tissue hypoxia → liver dysfunction → coagulopathy + brain hypoxia → coma → death)
Table 4.1 Causes of Shock | ||||||||||
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Classification of Shock
Compensated Shock
Vital organ perfusion maintained
Early signs of shock include heart rate and respiratory rate above expected
Blood pressure is maintained via vasoconstriction with perfusion to vital organs
Nonperfused areas of the body are hypoxic with progressive dysfunction
Note: In young children cardiac output is dependent on heart rate
Decompensated Shock
Hypotension and impaired tissue perfusion
First sign may be fatigue (e.g., infant with bronchiolitis and apneic episodes)
Slowing of the heart and/or respiratory rate to normal values without improvement in condition
Changes in peripheral perfusion: loss of peripheral pulses, capillary refill time > 3 seconds, changes in level of consciousness, and decreased urine output
A fall in blood pressure is a late sign and signals impending cardiopulmonary arrest
Table 4.2 Compensated vs Decompensated Shock | ||||||||||||
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Irreversible Shock
Multiorgan failure leading to death
May occur hours, days, or weeks after the episode
