Table 2.

Abnormalities leading to hypotension in various shock states, including septic shock

Shock type	Venous return	Pump function	Vascular tone	Other abnormalities	Examples
Cardiogenic	Normal or ↑	↓↓	Normal or ↑	Primary pump failure, may develop compensatory salt/water retention and increased vascular tone	Myocardial infarction, injury
Neurogenic	↓	↓↓	↓↓	Loss of inotropic/chronotropic input and vascular tone	High cervical transection, spinal anesthetic
Distributive	↓↓	Normal (may ↑ or ↓, depending on etiology and compensation)	↓	Mediators dilate a vascular tree that cannot be filled with the existing blood volume	Anaphylaxis, adrenal insufficiency, SIRS response
Septic	↓↓	↑ or normal, but can be ↓↓	↓↓	Dysfunctions in 1. Vascular tone leading to pooling of venous blood, 2. Myocardial pumping 3. Vascular tone, contributing to hypotension	Peritonitis, pneumonia, urosepsis

Key abnormalities are indicated by bold double arrow