Shock
Shock -The body's pathological response to illness, trauma or severe psychological or emotional stress.
Shock is a general term that indicates a failure of the circulatory system to support vital body functions.
A clinical picture of shock:
- At the onset of the shock syndrome, the changes in the physiological function of the cells is not detectable except for a possible increase in heart rate.
- As the condition progresses, blood is shunted away from the lungs, skin, kidneys and GI tract to provide needed O2 to the brain and heart.
- At this stage, the "Compensatory Stage", the following symptoms may be observed:
- Skin is cold and clammy
- Decreased urine output
- Increased respirations
- Normal BP
- Anxiety levels increase, may become uncooperative
- If allowed to progress beyond the Compensatory Stage, the mean arterial pressure - MAP (the average pressure within an artery over a complete cycle of one heartbeat) falls, all body systems are inadequately perfused, including the heart, which begins to fail to pump adequately.
- Peripheral circulation reacts to chemical mediators (a neurotransmitter chemical) released by the body and fluid leaks from the capillaries further decreasing volume of fluid in the circulation.
- Acute renal failure follows, then the liver, GI and hematological systems begin to fail.
- This stage is called the "Progressive Stage", symptoms of which follow:
- BP drops precipitously (rapidly)
- Respiration becomes rapid and shallow
- Severe pulmonary edema (fluid in the lungs) results from leakage of fluid from pulmonary capillaries
- Tachycardia (radid heartbeat) of up to 150 bpm
- Pt may complain of chest pain
Mental status changes are subtle at first, progressing from confusion to lethargy (state of sluggishness or inactivity) and later to unconsciousness
- If shock progresses beyond this point, it is called the "Irreversible" or "Refractory Stage"
- Recovery becomes unlikely
- Shock may be classified as hypovolemic , cardiogenic , obstructive , and distributive.