Difference between revisions of "Consequences of Gastric Disease - Pathology"

From WikiVet English
Jump to navigation Jump to search
m (Text replace - "[[Forestomach - Anatomy & Physiology|" to "[[Monogastric Stomach - Anatomy & Physiology|")
(3 intermediate revisions by the same user not shown)
Line 1: Line 1:
 
{{review}}
 
{{review}}
  
−
==[[Vomiting]]==
+
{{toplink
 +
|backcolour =BCED91
 +
|linkpage =Alimentary System - Pathology
 +
|linktext =Alimentary System
 +
|maplink = Alimentary System (Content Map) - Pathology
 +
|pagetype =Pathology
 +
|sublink1=Stomach and Abomasum - Pathology
 +
|subtext1=STOMACH AND ABOMASUM
 +
}}
 +
<br>
 +
==Vomiting==
 +
 
 +
* Has potentially lethal effects in the monogastric animal.
 +
 
 +
 
 +
===Water Loss===
 +
 
 +
* Fluid loss is evident as:
 +
*# An increased PCV or haematocrit.
 +
*# An increased total protein concentration.
 +
*# A prerenal azotaemia.
 +
 
 +
 
 +
===Gastric Electrolyte Loss===
 +
 
 +
* The main losses are of H<sup>+</sup> and Cl<sup>-</sup>, and also K<sup>+</sup>
 +
* Can potentially cause metabolic alkalosis, although this is only likely with disease which stops at the pylorus, e.g.: pyloric outflow obstruction.
 +
** In cases where mild alkalosis occurs, homeostatic mechanisms produce a more alkaline urine to restore normal body pH.
 +
** However, in severe metablolic alkalosis with marked dehydration, acidic urine may be produced- this is termed '''paradoxical aciduria'''.
 +
*** Because [[Control of Feeding - Anatomy & Physiology#The Vomit Reflex|vomiting]] induceses hypokalaemia, there is an overriding stimulus in the kidney for Na<sup>+</sup> (and therefore water) retention.
 +
*** Na+ can only be resorbed in exchange for H+
 +
**** H<sup>+</sup> is therefore excreted in the urine, causing it to be acidic.
 +
*** [[Control of Feeding - Anatomy & Physiology#The Vomit Reflex|Vomiting]] also induces hypochloraemia, meaning bicarbonate rather than chloride is resorbed with the Na+ to maintain electrical neutrality
 +
**** This perpetuates the alkalosis.
 +
* [[Control of Feeding - Anatomy & Physiology#The Vomit Reflex|Vomiting]] does not occur in the ruminant although [[The Abomasum - Anatomy & Physiology|abomasal]] content may reflux into the [[Stomach and Abomasum - Anatomy & Physiology|forestomachs]].
 +
** Sequestration of secretions in the [[The Abomasum - Anatomy & Physiology|abomasum]] will have similar effects to pyloric outflow obstruction with [[Control of Feeding - Anatomy & Physiology#The Vomit Reflex|vomiting]] in the monogastric animal.
 +
*** e.g. abomasal torsion
 +
*** Causes dehydration, hypochloraemia, hypokalaemia and metabolic alkalosis.
 +
 
 +
 
 +
* Lesions in the [[Small Intestine - Anatomy & Physiology|small intestine]] can also lead to [[Control of Feeding - Anatomy & Physiology#The Vomit Reflex|vomiting]]
 +
** Both gastric acid and pancreatic and intestinal bicarbonate secretions are lost
 +
*** Animal consequently has a normal pH or may even be acidotic.
  
 
==Raised Intraluminal pH==
 
==Raised Intraluminal pH==
Line 9: Line 51:
 
* Causes failure of digestion.  
 
* Causes failure of digestion.  
 
** Anorexia and weight loss follow.  
 
** Anorexia and weight loss follow.  
−
* Increases the number of bacteria in the [[Monogastric Stomach - Anatomy & Physiology|stomach]].
+
* Increases the number of bacteria in the [[Forestomach - Anatomy & Physiology|stomach]].
 
* Diarrhoea reults
 
* Diarrhoea reults
 
** Cause is unknwn is unknown but appears to be related to the elevated pH.
 
** Cause is unknwn is unknown but appears to be related to the elevated pH.
Line 23: Line 65:
 
* Is usually haemorrhagic in nature
 
* Is usually haemorrhagic in nature
 
** Due to bleeding from gastric ulceration.
 
** Due to bleeding from gastric ulceration.
−
[[Category:Stomach_and_Abomasum_-_Pathology]]
 
−
[[Category:To_Do_-_Clinical]]
 

Revision as of 14:19, 29 May 2010

 This article has been peer reviewed but is awaiting expert review. If you would like to help with this, please see more information about expert reviewing.


WikiPathWikiPath Banner.png
()Map ALIMENTARY SYSTEM (Map)
STOMACH AND ABOMASUM



Vomiting

  • Has potentially lethal effects in the monogastric animal.


Water Loss

  • Fluid loss is evident as:
    1. An increased PCV or haematocrit.
    2. An increased total protein concentration.
    3. A prerenal azotaemia.


Gastric Electrolyte Loss

  • The main losses are of H+ and Cl-, and also K+
  • Can potentially cause metabolic alkalosis, although this is only likely with disease which stops at the pylorus, e.g.: pyloric outflow obstruction.
    • In cases where mild alkalosis occurs, homeostatic mechanisms produce a more alkaline urine to restore normal body pH.
    • However, in severe metablolic alkalosis with marked dehydration, acidic urine may be produced- this is termed paradoxical aciduria.
      • Because vomiting induceses hypokalaemia, there is an overriding stimulus in the kidney for Na+ (and therefore water) retention.
      • Na+ can only be resorbed in exchange for H+
        • H+ is therefore excreted in the urine, causing it to be acidic.
      • Vomiting also induces hypochloraemia, meaning bicarbonate rather than chloride is resorbed with the Na+ to maintain electrical neutrality
        • This perpetuates the alkalosis.
  • Vomiting does not occur in the ruminant although abomasal content may reflux into the forestomachs.
    • Sequestration of secretions in the abomasum will have similar effects to pyloric outflow obstruction with vomiting in the monogastric animal.
      • e.g. abomasal torsion
      • Causes dehydration, hypochloraemia, hypokalaemia and metabolic alkalosis.


  • Lesions in the small intestine can also lead to vomiting
    • Both gastric acid and pancreatic and intestinal bicarbonate secretions are lost
      • Animal consequently has a normal pH or may even be acidotic.

Raised Intraluminal pH

  • Associated with some forms of gastritis.
    • e.g. Ostertagiasis
  • Causes failure of digestion.
    • Anorexia and weight loss follow.
  • Increases the number of bacteria in the stomach.
  • Diarrhoea reults
    • Cause is unknwn is unknown but appears to be related to the elevated pH.

Hyperacidity

  • May develop in certain gastric disturbances
  • Thought to be a contributory factor in peptic ulceration.

Anaemia

  • May also develop in certain gastric diseases
  • Is usually haemorrhagic in nature
    • Due to bleeding from gastric ulceration.
Retrieved from "https://en.wikivet.net/index.php?title=Consequences_of_Gastric_Disease_-_Pathology&oldid=63899"