Shock Flashcards
Why does shock occur?
Inadequate tissue perfusion
Types of shock
Septic Anaphylactic Cardiogenic Haemorrhagic Neurogenic
Definition of sepsis
An infection that triggers part of the systemic inflammatory response syndrome (SIRS)
Parts of SIRS
Body temp 36 - 38C
HP > 90
RR > 20
WBC > 12000 or < 4000
Diagnostic criteria for sepsis
Two or more features of SIRS with an infection
Define septic shock
Sepsis and refractory hypotension
Define severe sepsis
Sepsis + organ failure
What is released in the septic process?
Cytokines
Pathology of sepsis
Extensive cytokine release
Endothelial cell damage and neutrophil adhesion
Resulting in
- Excessive inflammation
- Coagulation and fibrinolytic suppression
Causes of shock in trauma patients
Haemorrhage Tension pneumothorax Spinal cord injury MI Cardiac tamponade
Most common cause of neurogenic shock
Spinal cord transection, usually at a high level
Pathology of neurogenic shock
Spinal cord transection
Resultant interruption of autonomic nervous system
Resulting in EITHER
- decreased sympathetic tone OR
- increased parasympathetic tone
Effect resulting in
- Decrease In peripheral vascular resistance mediated by marked vasodilation
- decreased preload and decreased CO
- decreased tissue perfusion and therefore shock
In contrast to other types of shock, what returns neurogenic shock to normal?
Peripheral vasoconstrictors
Main cause of cardiogenic shock
Ischaemic heart disease
Definition of anaphylaxis
Severe, life threatening, generalised or systemic hypersensivity reaction
