SHOCK

Definition.

Shock is syndrome of cardiovascular system failure resulting in adequate tissue perfusion.Hypotension is common but not universal feature.
The primary function of cardiovascular system is to maintain the perfusion of organs and tissues with oxygenated blood.Complex homeostatic mechanisms of exist to ensure that an adequate cardiac out put and blood pressure are maintained to meet the needs of individual.When these mechanisms fail,"shock" ensues,which uncorrected can result in organ failure,prolonged ICU stay and death.

Clinical features.

The clinical features vary depending on the cause and the physiological response.Two patterns are typically recognized,although there is a continuum from one to the other:
*. warm pink vasodilated,hyperdynamic patient with high cardiac output and hypotension.
*. Cold,grey,sweaty,vasoconstricted,peripherally shutdown patient with low cardiac output.Blood pressure may be maintained in the early stage.
Other features of shock may include increased or decreased core temperature,hypovetilation or hyperventilation,renal and hepatic dysfunction,disseminated intravascular coagulation,and altered mental status,and multiorgan dysfunction syndrome.

Aetiology.

1.Hypovolemia
2.Cardiogenic
3.Mechanical/obstructive
4.Altered systemvascular resistence

Management.

Apart from the mechanical causes of shock,in which relief of the mechaniical obstruction may take priority,the principles of managing shock states are similar in all regardless of aetiology,they include :
a. Optimizing of oxygen delivery
b. Optimizing of cardiac output
c. Optimizing of blood pressure
d. Treathment of underlying pathology
e. Support of any organ failure.