3. Physiology
        3.2. Cardiovascular
            3.2.6. Special circumstances
                3.2.6.3. Haemorrhage
3.2.6.3.1. Refractory shock

Refractory shock

[Ref: BL8:p283-285; WG21:p642]

 

Characterised by positive feedback

Acidosis

Decreased perfusion may lead to increase anaerobic glycolysis, resulting in lactic acidosis

Resulting in:

--> Aggravate fall in BP

Heart failure

 

Severe CNS ischaemia

Depression of cardiovascular centres in the brainstem

--> Reduced sympathetic tone

--> Drop in BP

 

Alterations in coagulation

--> Further bleeding and drop in BP

 

Depression of reticuloendothelial system

Endotoxins from normal bacteria flora in intestines are normally inactivated by RES, mainly in the liver

When RES is depressed, endotoxins invade the circulation

--> Produce profound generalised vasodilation

 

Other notes

Acute respiratory distress syndrome

Late complication of shock

Damage to capillary endothelial cells and alveolar epithelial cells

--> Release of cytokines

 

 

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