Shock Flashcards
Shock - Definitiion
Inadequate blood flow resulting in tissue hypoxia
Goal of Care
Rapid transport to hospital. Fluid resuscitation where appropriate
Overview
pts in shock from any cause are critically ill and survival is dependent upon rapid appropriate therapy specific to the cause
Shock is a clinical diagnosis: signs include inadequate perfusion of the skin - cold, clammy, cyanotic
inadequate perfusion of the CNS - agitation, confusion, lethargy and coma
BP of 90 systolic is commonly used as a cut off to define shock but this is not universal and depends on the pts usual pressure
Stages of Shock - Compensated
is associated w/ some decreased tissue perfusion but the bodys compensatory responses are sufficient to overcome the decreas in available fluid.
An increase in catecholamine production maintains cardiac output and a normal systolic blood pressure. Perfusion to vital organs is maintained by moving blood flow from the non-vital organs (eg skin) causing the initial symptoms of cold and clammy skin
Stages of Shock - Uncompensated Shock
occurs when the body is no longer able to maintain blood pressure. As the bodys compensatory mechanisms begin to fail, systolic pressure drops and signs of vital organ ischemia appear
Categories of Shock
- Hypovolemic
- Distributive
- Obstructive
- Cardiogenic
Hypovolemic Shock
Critical decrease in intravascular volume
- Hemorrhagic
- Vomiting/diarrhea
- Burns
Distributive Shock
Inadequate intravascular volume due to vasodilation
Increased capacity for blood to pool in the vascular bed
- Anaphylaxis
- Sepsis
- Neurogenic associated w/ brain or spinal cord injury
Obstructive Shock
Reduction in cardiac output usually associated w/ obstruction (mechanical or pressure) in the cardiopulmonary circuit
- Cardiac tamponade
- Tension pneumothorax
- Pulmonary embolus
Cardiogenic Shock
Inability of the heart to pump efficiently
- AMI
- Arrhythmia
- Valve failure
- Ruptured cardiac septum
Guiding Principles
Causes of shock requiring specific treatment in the field:
Anaphylaxis - EPI
Hypovolemia - Fluid
Tension pneumothorax - Chest decompression
Arrhythmia - Cardioversion
Special Note
IV fluids should be used judiciously in pts w/ cardiogenic shock. Discuss the case w/ an EP if possible prior to administering a fluid challenge to theses pts
Intervention Guidelines EMR/PCP
EMR
- Keep pt at rest
- Supp O2
- Position pt
- Consider possibility of anaphylaxis
- Facilitate rapid transport
- Provide warmth
- Assess for likely cause of shock
PCP
All above, plus:
- IV during transport
Correct hypoperfusion - hypotension BP <90
- Fluid challenge if no pulmonary edema
NS upto 2L - reassess BP and lungs every 500cc - target 90 systolic
Intervention Guidelines - ACP
- Consider Arrhythmia
- Tension pneumothorax
Further Care
- Fluid resuscitation including blood products and colloid solutions
- Central line
- Blood gas. Lab monitoring
- Sepsis management
- Steroids
- Radiology diagnostics
- Pressor support
- Surgery
