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GSACEP core man LECTURE
series:
SCHOCK
Brian Kitamura
MD, CPT, USARNG
Updated: 20APR2013
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Disclaimer
Views and opinions expressed do not
necessarily reflect those of GS-ACEP,
The Department of Defense, the U.S.
Army, the U.S. Government, or any
other governmental or nongovernmental
organization unless explicitly stated.
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Outline
Shock Definition
Types of Shock
Cardiogenic
Distributive
Obstructive
Hypovolemic
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Definition of Shock
“Shock is circulatory insufficiency that creates
an imbalance between tissue oxygen supply
(delivery) and oxygen demand (consumption).”
Tintinalli’s Emergency Medicine, 7th ed
“In philosophic terms, shock [is the] transition
between life and death”
Rosen’s Emergency Medicine, 7th ed
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Definition of Shock
In short, the tissues are not getting the oxygen
they require
Can often be qualified as a “fluids,” “pump,” or
“pipes” problem
It really is all plumbing
Pulmonary and toxicologic causes of
shock are outside the scope of the lecture
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Definition of Shock
Bedside determination of shock
Systolic Blood Pressure < 90
Mean Arterial Pressure < 65
Shock index > 1 (Heart Rate/Systoilc BP)
Elevated Lactate
Decreased level of consciousness with brain injury
All just general guidlelines
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Cardiogenic Shock
“Pump Problems”
Essentially heart failure
Caused by:
Acute Myocardial Ischemia
Cardiomyopathy
Dysrhythmias
Structural damage
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Cardiogenic Shock
Acute MI
Heart Muscle is stunned or dead
Blood flow is restricted to an area of muscle
Muscle doesn’t contract properly
Treatment
Relieve the blockage: Aspirin, thrombolytics,
stents/angioplasty, bypass
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Cardiogenic Shock
Congestive Heart Failure
Heart muscle is globally weak
Multiple heart attacks, high blood pressure,
weakened ventricles, stiff ventricles
Fluid overload stretches the heart
Treatment
Optimize the physiology
Decrease blood pressure
Decrease volume
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Cardiogenic Shock
Dysrhythmia
Irregular rhythm prevents forward flow of
blood
Treatment
Cardioversion/Defibrilation, antiarrhythmics
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Cardiogenic Shock
Structural Disturbances
Penetrating trauma
Valve disorders
Treatment:
Cold steel
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Cardiogenic Shock
Structural Disturbances
Penetrating trauma
Valve disorders
Treatment:
Cold steel
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Distributive Shock
“Pipe Problem”
Leaky blood vessels (microscopic)
Lack of vascular tone or “squeeze”
“Warm Shock”
Septic Shock
Anaphylactic Shock
Neurogenic Shock
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Septic Shock
Infection causes release of inflammatory
signals
Blood vessels “leak” to allow more blood flow,
infection fighting cells out into the tissues
System is overrun in shock
Treatment
Provide fluids first, then pressors
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Anaphylactic Shock
Massive, rapid, histamine release in response
to a specific antigen
Blood vessels dilate and leak
Treatment
EPINEPHRINE!
Benadryl, Steroids
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Neurogenic Shock
Brain or spinal cord injury
Neurologic system has constant control
over vascular tone
If input is lost, vessels dilate
Treatment
Vasopressors
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Obstructive Shock
Blockage prevents forward movement of blood
Pulmonary Embolism
Tension Pneumothorax
Cardiac Tamponade
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Pulmonary Embolism
Blood clot from the venous system gets
lodged in the lungs
Common post traumatic patients
Treatment:
Difficult, but we use anticoagulants, lytics 18
Tension Pneumothorax
Pressure builds up in the chest preventing
return of venous blood
Seen in
chest trauma
Treatment:
Needle decompression, chest tube
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Cardiac Tamponade
Pressure builds up in the pericardial sac
Seen in
chest trauma
Treatment:
Pericardiocentesis
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Hypovolemic Shock
“Fluid Problem”
Loss of fluid
Loss of blood
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Hypovolemia
Non-blood losses decrease plasma volume
Sweating
GI Losses
Inadequate
Intake
Treatment: Replace fluids - oral or IV
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Hemorrhage
Just like is sounds, someone is bleeding out
Trauma
GI Bleeding
Stop the bleeding
Resuscitate with crystalloids first, blood
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if needed.
In summary
Shock is inadequate perfusion
Treat underlying causes if possible
Resuscitate based on cause
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References
Tintinalli’s Emergency Medicine

7th Edition
Rosen’s Emergency Medicine
7th Edition
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