Distributive shock

Definition:  Distributive shock refers to a group of shock subtypes caused by profound peripheral vasodilatation despite normal or high cardiac output.

Causes of distributive shock

1) Septic shock – the commonest among the group & clinically very important. 

2) Neurogenic shock

- Usually occurs in the setting of anaesthetic procedure [cephalo-caudal migration of anaesthetic agent] or spinal cord injury owing to loss of vascular tone & peripheral pooling of blood. 

3) Anaphylactic shock 

- Initiated by generalized IgE – mediated hypersensitivity response, associated with systemic vasodilatation & increased vascular permeability. 

4) Endocrine shock 

- This is a type of shock that typically occurs in adrenal insufficiency. 

 Next, we will discuss septic shock in some detail. But before discussing septic shock in detail it would be useful to know some aspects of sepsis briefly. Bactermia is the presence of viable bacteria in the blood as evidenced by blood culture.  Septicemia  is systemic infection due the presence of microbes and their toxin the blood.  Sepsis is a systemic response to severe infection mediated via macrophage-derived cytokines that target end organ receptors in response to infection. It is also called SIRS. 

References

Bezabeh ,M. ; Tesfaye,A.; Ergicho, B.; Erke, M.; Mengistu, S. and Bedane,A.; Desta, A.(2004). General Pathology. Jimma University, Gondar University Haramaya University, Dedub University.