53 bytes removed ,  15:08, 16 September 2010
no edit summary
Line 1: Line 1:  
{{review}}
 
{{review}}
 
==What is Shock?==
 
==What is Shock?==
 +
"Shock" is a clinical term to describe a condition in which:
 +
* The body temperature is subnormal.
 +
* Reflexes are subnormal.
 +
* Respiration is shallow.
 +
* There is a rapid thready pulse.
   −
* "Shock" is a clinical term to describe a condition in which:
+
==Causes of Shock==
** The body temperature is subnormal.
  −
** Reflexes are subnormal.
  −
** Respiration is shallow.
  −
** There is a rapid thready pulse.
     −
==Cause of Shock==
+
The cause of the clinical signs of shock is circulatory failure, which results in impaired perfusion of tissues and inadequate cellular oxygenation. There are several different circumstances that might lead to the development of shock, such as:
   −
* The cause of shock is circulatory failure.
+
===Hypovolaemia===
** This leads to impaired perfusion of tissues, resulting in inadequate cellular oxygenation.
+
This is caused by massive reduction in circulating blood volume; for example due to loss in  
 
+
severe haemorrhage or extensive body burns where there is excessive loss of tissue fluid from the injured area.
==Types of Shock==
  −
 
  −
===Hypovolaemic shock===
  −
 
  −
* This is caused by massive reduction in circulating blood volume.
  −
** For example, due to loss in  
  −
*** Severe haemorrhage.
  −
*** Extensive body burns.
  −
**** There is excessive loss of tissue fluid from the injured areas.
      
===Trauma, pain and major surgery===
 
===Trauma, pain and major surgery===
 +
These factors can affect the vasomotor control of the peripheral circulation; the capillaries become dilated and blood pools in the peripheral circulation. A secondary hypovolaemia then occurs.
   −
* Trauma, pain and minor surgery affect the vasomotor control of the peripheral circulation.
+
===Endotoxaemia===
* The capillaries become dilated and blood pools in the peripheral circulation.
+
Endotoxaemia can occur in severe infections by Gram negative bacteria. The toxins produced by the bacteria are thought to induce blood clotting in very small vessels, occluding blood flow and resulting in blood pools in the peripheral tissues. Endotoxaemia is a risk factor for the development of [[Disseminated Intravascular Coagulation|Disseminated Intravascular Coagulation]].
** A secondary hypovolaemia occurs.
  −
 
  −
===Endotoxic shock===
  −
 
  −
* Endotoxic shock occurs in severe infections by Gram negative bacteria.  
  −
* The toxins produced by the bacteria are thought to induce clotting of the blood in very small vessels.
  −
** The flow is blocked and blood pools in the peripheral tissues.
  −
thereby blocking the flow and causing pooling of blood in the peripheral
  −
* The condition is known as [[Disseminated Intravascular Coagulation|Disseminated Intravascular Coagulation]].
  −
 
  −
===Cardiogenic shock===
     −
* Cardiogenic shock occurs when a suddenly developing cardiac failure causes circulatory collapse, e.g.
+
===Cardiac disruption===
** Myocardial infarction
+
Acute cardiac malfunction such as myocardial infarction, severe arrhythmias or sudden failure of the valves can cause circulatory collapse.
** Severe arrhythmia
  −
** Sudden failure of the valves.
      
==Pathophysiology of Shock==
 
==Pathophysiology of Shock==
5,582

edits