Difference between revisions of "Gastric Dilation and Rupture - Horse"

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{{unfinished}}
  
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Also known as: '''''Gastric Rupture
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{| cellpadding="10" cellspacing="0" border="1"
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| Also known as:
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|'''Gastric Rupture'''
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|}
  
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==Introduction==
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{| cellpadding="10" cellspacing="0" border="1"
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| See also:
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|'''[[Colic, Gastric Causes]]'''
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|}
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==Description==
 
Gastric dilation in the horse may be primary, secondary or idiopathic.<ref name="Sanchez">Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref>
 
Gastric dilation in the horse may be primary, secondary or idiopathic.<ref name="Sanchez">Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref>
−
 
−
See also: '''[[Colic, Gastric Causes|Gastric causes of colic]]'''
 
  
 
==Aetiology==
 
==Aetiology==
  
−
<u>'''Primary causes:'''</u>
+
*'''Primary causes:''' [[Gastric Impaction - Horse|gastric impaction]], food engorgement, excessive water intake after exercise, aerophagia, ''[[Gasterophilus spp.|Gasterophilus]]'' infestation and [[Habronema and Draschia spp.|habrenomiasis]].<ref name="Camp">Campbell-Thompson, M.L, Merritt, A.M (1999) Alimentary system: diseases of the stomach.  In Colahan, P.T, Mayhew, I.G, Merritt, A.M, Moore, J.N ''Equine medicine and surgery'', St Louis, Mosby, pp 699-715.  In: Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref><ref name="Todhunter">Todhunter, R.J, Erb, H.N, Roth, L (1986) Gastric rupture in horses: a review of 54 cases. ''Equine Vet J'', 30:344-348.</ref>  Excessive consumption of fermentable feeds (grains, lush grass, and beet pulp) causes a large increase in the production of volatile fatty acids which is thought to delay gastric emptying.<ref name="Merck">Merck & Co (2008) '''The Merck Veterinary Manual (Eighth Edition)''', ''Merial''.</ref>
−
 
+
*'''Secondary causes:''' primary intestinal ileus or small or large intestinal obstruction. Dilation resulting from small intestinal obstruction is the most common cause.  Fluid from the obstructed small intestine accumulates in the stomach, causing [[Colic Diagnosis - Naso-gastric Intubation|nasogastric reflux]]. Gastric dilation may also occur with certain colonic displacements, especially [[Large Colon, Right Dorsal Displacement - Horse|right dorsal displacement of the colon]] around the caecum. It is hypothesised that the displaced colon obstructs duodenal outflow. Gastric fluid accumulation is also characteristic of '''proximal enteritis-jejunitis'''.<ref name="Merck">Merck & Co (2008) '''The Merck Veterinary Manual (Eighth Edition)''', ''Merial''.</ref>
−
[[Gastric Impaction - Horse|Gastric impaction]], food engorgement, excessive water intake after exercise, aerophagia, ''[[Gasterophilus spp.|Gasterophilus]]'' infestation and [[Habronema and Draschia spp.|habrenomiasis]].<ref name="Camp">Campbell-Thompson, M.L, Merritt, A.M (1999) Alimentary system: diseases of the stomach.  In Colahan, P.T, Mayhew, I.G, Merritt, A.M, Moore, J.N ''Equine medicine and surgery'', St Louis, Mosby, pp 699-715.  In: Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref><ref name="Todhunter">Todhunter, R.J, Erb, H.N, Roth, L (1986) Gastric rupture in horses: a review of 54 cases. ''Equine Vet J'', 30:344-348.</ref>  Excessive consumption of fermentable feeds (grains, lush grass, and beet pulp) causes a large increase in the production of volatile fatty acids which is thought to delay gastric emptying.<ref name="Merck">Merck & Co (2008) '''The Merck Veterinary Manual (Eighth Edition)''', ''Merial''.</ref>
 
−
 
 
−
<u>'''Secondary causes:'''</u>
 
−
 
 
−
Primary intestinal ileus or small or large intestinal obstruction. Dilation resulting from small intestinal obstruction is the most common cause.  Fluid from the obstructed small intestine accumulates in the stomach, causing nasogastric reflux. Gastric dilation may also occur with certain colonic displacements, especially [[Large Colon, Right Dorsal Displacement - Horse|right dorsal displacement of the colon]] around the caecum. It is hypothesised that the displaced colon obstructs duodenal outflow. Gastric fluid accumulation is also characteristic of '''proximal enteritis-jejunitis'''.<ref name="Merck">Merck & Co (2008) '''The Merck Veterinary Manual (Eighth Edition)''', ''Merial''.</ref>
 
  
 
Untreated, gastric dilation can rapidly lead to '''gastric rupture''' whereby the stomach usually tears along its greater curvature.  It has been proposed that the '''seromuscularis''' weakens and tears before the gastric mucosa.<ref name="Todhunter">Todhunter, R.J, Erb, H.N, Roth, L (1986) Gastric rupture in horses: a review of 54 cases. ''Equine Vet J'', 30:344-348.</ref><ref name="Kiper">Kiper, M.L, Traub-Dargatz, J, Curtis, C.R (1990) Gastric rupture in horses: 50 cases (1979-1987), ''J Am Vet Med Assoc'', 196:333-336.  In: Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref>  Most cases of rupture occur secondary to mechanical obstruction, ileus, and trauma.  The rest are due to overload or idiopathic causes.<ref name="Merck">Merck & Co (2008) '''The Merck Veterinary Manual (Eighth Edition)''', ''Merial''.</ref>  Rupture can occur secondary to [[Gastric Ulceration - Horse|gastric ulceration]], in which case full-thickness tearing usually occurs in all layers of the gastric wall.<ref name="Sanchez">Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref>  Certain '''risk factors''' have been identified for gastric rupture<ref name="Todhunter">Todhunter, R.J, Erb, H.N, Roth, L (1986) Gastric rupture in horses: a review of 54 cases. ''Equine Vet J'', 30:344-348.</ref><ref name="Kiper">Kiper, M.L, Traub-Dargatz, J, Curtis, C.R (1990) Gastric rupture in horses: 50 cases (1979-1987), ''J Am Vet Med Assoc'', 196:333-336.  In: Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref> including:
 
Untreated, gastric dilation can rapidly lead to '''gastric rupture''' whereby the stomach usually tears along its greater curvature.  It has been proposed that the '''seromuscularis''' weakens and tears before the gastric mucosa.<ref name="Todhunter">Todhunter, R.J, Erb, H.N, Roth, L (1986) Gastric rupture in horses: a review of 54 cases. ''Equine Vet J'', 30:344-348.</ref><ref name="Kiper">Kiper, M.L, Traub-Dargatz, J, Curtis, C.R (1990) Gastric rupture in horses: 50 cases (1979-1987), ''J Am Vet Med Assoc'', 196:333-336.  In: Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref>  Most cases of rupture occur secondary to mechanical obstruction, ileus, and trauma.  The rest are due to overload or idiopathic causes.<ref name="Merck">Merck & Co (2008) '''The Merck Veterinary Manual (Eighth Edition)''', ''Merial''.</ref>  Rupture can occur secondary to [[Gastric Ulceration - Horse|gastric ulceration]], in which case full-thickness tearing usually occurs in all layers of the gastric wall.<ref name="Sanchez">Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref>  Certain '''risk factors''' have been identified for gastric rupture<ref name="Todhunter">Todhunter, R.J, Erb, H.N, Roth, L (1986) Gastric rupture in horses: a review of 54 cases. ''Equine Vet J'', 30:344-348.</ref><ref name="Kiper">Kiper, M.L, Traub-Dargatz, J, Curtis, C.R (1990) Gastric rupture in horses: 50 cases (1979-1987), ''J Am Vet Med Assoc'', 196:333-336.  In: Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref> including:
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==Diagnosis==
 
==Diagnosis==
 +
 
'''Primary gastric dilation''' should be suspected if there are copious amounts of [[Colic Diagnosis - Naso-gastric Intubation|gastric reflux]] in the absence of small intestinal distension on [[Colic Diagnosis - Rectal Examination|rectal examination]] and the absence of endotoxaemia.<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>  A retrospective diagnosis of '''primary gastric dilation''' can be made if colic signs cease following decompression, and other clinical parameters return to normal.  Primary gastric dilation does not cause any significant change in peritoneal fluid parameters until rupture occurs.<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>
 
'''Primary gastric dilation''' should be suspected if there are copious amounts of [[Colic Diagnosis - Naso-gastric Intubation|gastric reflux]] in the absence of small intestinal distension on [[Colic Diagnosis - Rectal Examination|rectal examination]] and the absence of endotoxaemia.<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>  A retrospective diagnosis of '''primary gastric dilation''' can be made if colic signs cease following decompression, and other clinical parameters return to normal.  Primary gastric dilation does not cause any significant change in peritoneal fluid parameters until rupture occurs.<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>
  
−
'''Secondary gastric dilation''' should be considered if there is persistent [[Colic Diagnosis - Clinical Signs|colic]], repeated retrieval of [[Colic Diagnosis - Naso-gastric Intubation|nasogastric reflux]], intestinal distension on [[Colic Diagnosis - Rectal Examination|rectal examination]] and clinical signs of endotoxaemia.<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>  These are all indications for '''exploratory laparotomy''' to look for an intestinal obstruction.   
+
'''Secondary gastric dilation''' should be considered if there is persistent [[Colic Diagnosis - Clinical Signs|colic]], repeated retrieval of [[Colic Diagnosis - Naso-gastric Intubation|nasogastric reflux]], intestinal distension on [[Colic Diagnosis - Rectal Examination|rectal examination]] and clinical signs of [[Colic Diagnosis - Clinical Signs|endotoxaemia]].<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>  These are all indications for '''exploratory laparotomy''' to look for an intestinal obstruction.   
  
 
NB: ''excessive fluid within the stomach is not always detected by nasogastric intubation, despite repeated attempts with frequent repositioning of the tube. Furthermore, gastric impaction with solid food material may be too firm to be retrieved by this method.''<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>   
 
NB: ''excessive fluid within the stomach is not always detected by nasogastric intubation, despite repeated attempts with frequent repositioning of the tube. Furthermore, gastric impaction with solid food material may be too firm to be retrieved by this method.''<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>   
  
−
'''Gastric rupture''' results in septic peritonitis which will be reflected in the [[Colic - Peritoneal Fluid Analysis|nature of fluid collected by abdominocentesis]]<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>:
+
'''Gastric rupture''' results in septic peritonitis which will be reflected in the nature of fluid collected by [[Colic Diagnosis - Abdominocentesis|abdominocentesis]]<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>:
 
*Foetid, turbid sample containing particulate matter
 
*Foetid, turbid sample containing particulate matter
 
*White cell count >40 x 10<sup>9</sup>/l
 
*White cell count >40 x 10<sup>9</sup>/l
Line 65: Line 68:
  
 
==Treatment==
 
==Treatment==
−
'''[[Colic, Medical Treatment|Medical treatment]]:'''
 
  
−
If anatomical obstructions have been ruled out, '''prokinetic agents''' such as '''metoclopramide''' or '''bethanecol''' may prove useful to restore gastric motility, especially in the presence of post-operative ileus.  Unfortunately, metaclopramide causes neurological side effects and bethanecol produces dose-related gastrointestinal problems including colic, diarrhoea and salivation.<ref>Murray, M.J (1990) Gastric ulceration.  In: Smith, B.P, '''Large Animal Internal Medicine''', ''CV Mosby Publishing Company'', USA, pp 648-652.  In: Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>  '''Nonsteroidal anti-inflammatory drugs (NSAIDs)''' such as '''flunixin meglumine''' and '''phenylbutazone''' may also be beneficial in post operative ileus to help combat the effects of endotoxin.  It is crucial that '''gastric decompression''' is maintained in cases of delayed gastric emptying.  This can be achieved with an indwelling nasogastric tube, (although prolonged intubation carries its own risk) or by repeated intubation.  '''IV fluid therapy''' should be given to ensure adequate hydration.<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>
+
*'''[[Colic, Medical Treatment|Medical treatment]]:''' if anatomical obstructions have been ruled out, '''prokinetic agents''' such as '''metoclopramide''' or '''bethanecol''' may prove useful to restore gastric motility, especially in the presence of post-operative ileus.  Unfortunately metaclopramide causes neurological side effects and bethanecol produces dose-related gastrointestinal problems including colic, diarrhoea and salivation.<ref>Murray, M.J (1990) Gastric ulceration.  In: Smith, B.P, '''Large Animal Internal Medicine''', ''CV Mosby Publishing Company'', USA, pp 648-652.  In: Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>  '''Nonsteroidal anti-inflammatory drugs (NSAIDs)''' such as '''flunixin meglumine''' and '''phenylbutazone''' may also be beneficial in post operative ileus to help combat the effects of endotoxin.  It is crucial that '''gastric decompression''' is maintained in cases of delayed gastric emptying.  This can be achieved with an indwelling nasogastric tube, (although prolonged intubation carries its own risk) or by repeated intubation.  '''IV fluid therapy''' should be given to ensure adequate hydration.<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>
  
−
'''Surgical treatment''':  
+
*'''Surgical treatment''': the surgical options for managing gastric disease are limited since the equine stomach is diffcult to access surgically.  Extending the midline laparotomy incision cranially may improve access slightly but also increases the risk of post operative wound problems.<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>  Gastrotomy and removal of impacted food material has been reported<ref>Clayton-Jones, D.G, Greatorex, J.C, Stockman, M.J.R, Harris, C.P.J (1972) Gastric impaction in a pony: Relief via laparotomy.  ''Equine Vet J'', 4:98-99.  In: Proudman, C.J, Baker, S.J (1994) ''Satellite Article'': Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>but carries a high risk of gross peritoneal contamination. For gastric rupture, surgical success has been reported for repairing partial thickness tears<ref>Steenhaut, M, Vlaminck, K, Gasthuys, F (1986) Surgical repair of a partial gastric rupture in a horse.  ''Equine Vet J'', 18:331-332.  In: Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref> and also in one case of a full thickness rupture.<ref>Hogan, P.M, Bramlage, L.R, Pierce, S.W (1995) Repair of a full-thickness gastric rupture in a horse.  ''J Am Vet Med Assoc'', 207:338-340.  In: Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref>
−
 
 
−
The surgical options for managing gastric disease are limited since the equine stomach is difficult to access surgically.  Extending the midline laparotomy incision cranially may improve access slightly but also increases the risk of post operative wound problems.<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref>  Gastrotomy and removal of impacted food material has been reported<ref>Clayton-Jones, D.G, Greatorex, J.C, Stockman, M.J.R, Harris, C.P.J (1972) Gastric impaction in a pony: Relief via laparotomy.  ''Equine Vet J'', 4:98-99.  In: Proudman, C.J, Baker, S.J (1994) ''Satellite Article'': Gastric disease in the adult horse: a clinical perspective.  ''Equine Vet Educ'', 6(4):178-184.</ref> but carries a high risk of gross peritoneal contamination. For gastric rupture, surgical success has been reported for repairing partial thickness tears<ref>Steenhaut, M, Vlaminck, K, Gasthuys, F (1986) Surgical repair of a partial gastric rupture in a horse.  ''Equine Vet J'', 18:331-332.  In: Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref> and also in one case of a full thickness rupture.<ref>Hogan, P.M, Bramlage, L.R, Pierce, S.W (1995) Repair of a full-thickness gastric rupture in a horse.  ''J Am Vet Med Assoc'', 207:338-340.  In: Sanchez, L.C (2010) ''Other Disorders of the Stomach'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 15.</ref>
 
  
 
==Prognosis==
 
==Prognosis==
−
The prognosis for survival may be excellent in most cases of gastric dilation<ref name="Merck">Merck & Co (2008) '''The Merck Veterinary Manual (Eighth Edition)''', ''Merial''.</ref> but gastric rupture is usually '''fatal''' because of widespread contamination of the peritoneal cavity, septic peritonitis, and septic shock. '''Food engorgement''' also carries the risk of secondary laminitis.
+
The prognosis for survival may be excellent in most cases of gastric dilation<ref name="Merck">Merck & Co (2008) '''The Merck Veterinary Manual (Eighth Edition)''', ''Merial''.</ref> but gastric rupture is usually '''fatal''' because of widespread contamination of the peritoneal cavity, septic peritonitis, and septic shock. '''Food engorgement''' also carries the risk of secondary [[laminitis]].
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{{Learning
 
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|flashcards = [[Equine Internal Medicine Q&A 01]]
 
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|literature search = [http://www.cabdirect.org/search.html?q=title:(gastric)+AND+(title:(dilat*)+OR+title:(ruptur*))+AND+od:(horses) Gastric Dilatation or Rupture in horses publications]
 
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==References==
 
==References==
 
<references/>
 
<references/>
  
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[[Category:To_Do_-_Nina]]
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{{review}}
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[[Category:To_Do_-_Review]]
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==Webinars==
 
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<rss max="10" highlight="none">https://www.thewebinarvet.com/gastroenterology-and-nutrition/webinars/feed</rss>
 
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[[Category:Expert_Review - Horse]]
 
 
[[Category:Surgical_Colic_in_the_Horse]]
 
[[Category:Surgical_Colic_in_the_Horse]]
 
[[Category:Colic - Gastric Causes]]
 
[[Category:Colic - Gastric Causes]]
 
[[Category:Medical Colic in the Horse]]
 
[[Category:Medical Colic in the Horse]]
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[[Category:Stomach Diseases - Horse]]
 

Revision as of 21:43, 6 October 2010


 This article is still under construction.


Also known as: Gastric Rupture
See also: Colic, Gastric Causes

Description

Gastric dilation in the horse may be primary, secondary or idiopathic.[1]

Aetiology

  • Primary causes: gastric impaction, food engorgement, excessive water intake after exercise, aerophagia, Gasterophilus infestation and habrenomiasis.[2][3] Excessive consumption of fermentable feeds (grains, lush grass, and beet pulp) causes a large increase in the production of volatile fatty acids which is thought to delay gastric emptying.[4]
  • Secondary causes: primary intestinal ileus or small or large intestinal obstruction. Dilation resulting from small intestinal obstruction is the most common cause. Fluid from the obstructed small intestine accumulates in the stomach, causing nasogastric reflux. Gastric dilation may also occur with certain colonic displacements, especially right dorsal displacement of the colon around the caecum. It is hypothesised that the displaced colon obstructs duodenal outflow. Gastric fluid accumulation is also characteristic of proximal enteritis-jejunitis.[4]

Untreated, gastric dilation can rapidly lead to gastric rupture whereby the stomach usually tears along its greater curvature. It has been proposed that the seromuscularis weakens and tears before the gastric mucosa.[3][5] Most cases of rupture occur secondary to mechanical obstruction, ileus, and trauma. The rest are due to overload or idiopathic causes.[4] Rupture can occur secondary to gastric ulceration, in which case full-thickness tearing usually occurs in all layers of the gastric wall.[1] Certain risk factors have been identified for gastric rupture[3][5] including:

  • Feeding grass hay
  • Not feeding grain
  • Gelding
  • Non-automatic water sources

Clinical signs

Gastric dilation usually produces:

  • Acute, severe colic
  • Tachycardia
  • Pale mucous membranes
  • Retching[4]
  • Ingesta at the nares in severe cases (rare)
  • Gastric reflux

NB: the time to development of reflux is proportional to the distance to the intestinal segment involved, (e.g. 4 hours with duodenal obstruction[6]). Furthermore, nasogastric intubation does not preclude the possibility of gastric rupture.[3]

Gastric rupture typically results in:

  • Relief
  • Depression

The inevitable peritonitis and endotoxic shock will lead to:

  • Reluctance to move[7]
  • Tachypnoea
  • Tachycardia
  • Sweating
  • Muscle fasciculations
  • Blue or purple mucous membranes[7]

NB: rupture of a stomach containing dry, fibrous material may produce a more insidious onset of clinical signs of peritonitis than rupture of a fluid distended viscus. This is probably because it takes longer for the dry gastric contents to disperse around the peritoneum.[7]

Diagnosis

Primary gastric dilation should be suspected if there are copious amounts of gastric reflux in the absence of small intestinal distension on rectal examination and the absence of endotoxaemia.[7] A retrospective diagnosis of primary gastric dilation can be made if colic signs cease following decompression, and other clinical parameters return to normal. Primary gastric dilation does not cause any significant change in peritoneal fluid parameters until rupture occurs.[7]

Secondary gastric dilation should be considered if there is persistent colic, repeated retrieval of nasogastric reflux, intestinal distension on rectal examination and clinical signs of endotoxaemia.[7] These are all indications for exploratory laparotomy to look for an intestinal obstruction.

NB: excessive fluid within the stomach is not always detected by nasogastric intubation, despite repeated attempts with frequent repositioning of the tube. Furthermore, gastric impaction with solid food material may be too firm to be retrieved by this method.[7]

Gastric rupture results in septic peritonitis which will be reflected in the nature of fluid collected by abdominocentesis[7]:

  • Foetid, turbid sample containing particulate matter
  • White cell count >40 x 109/l
  • Protein content >30g/l.

Findings on rectal examination may include[7]:

  • A 'gritty feeling' on the serosal surfaces of intestine due to adherent food material
  • An impression of 'space' in the abdomen due to gas in the peritoneal cavity.

Laboratory findings[2] may include:

  • Haemoconcentration
  • Hypokalaemia
  • Hypochloraemia

Treatment

  • Medical treatment: if anatomical obstructions have been ruled out, prokinetic agents such as metoclopramide or bethanecol may prove useful to restore gastric motility, especially in the presence of post-operative ileus. Unfortunately metaclopramide causes neurological side effects and bethanecol produces dose-related gastrointestinal problems including colic, diarrhoea and salivation.[8] Nonsteroidal anti-inflammatory drugs (NSAIDs) such as flunixin meglumine and phenylbutazone may also be beneficial in post operative ileus to help combat the effects of endotoxin. It is crucial that gastric decompression is maintained in cases of delayed gastric emptying. This can be achieved with an indwelling nasogastric tube, (although prolonged intubation carries its own risk) or by repeated intubation. IV fluid therapy should be given to ensure adequate hydration.[7]
  • Surgical treatment: the surgical options for managing gastric disease are limited since the equine stomach is diffcult to access surgically. Extending the midline laparotomy incision cranially may improve access slightly but also increases the risk of post operative wound problems.[7] Gastrotomy and removal of impacted food material has been reported[9]but carries a high risk of gross peritoneal contamination. For gastric rupture, surgical success has been reported for repairing partial thickness tears[10] and also in one case of a full thickness rupture.[11]

Prognosis

The prognosis for survival may be excellent in most cases of gastric dilation[4] but gastric rupture is usually fatal because of widespread contamination of the peritoneal cavity, septic peritonitis, and septic shock. Food engorgement also carries the risk of secondary laminitis.

References

  1. ↑ 1.0 1.1 Sanchez, L.C (2010) Other Disorders of the Stomach in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) Equine Internal Medicine (Third Edition), Saunders, Chapter 15.
  2. ↑ 2.0 2.1 Campbell-Thompson, M.L, Merritt, A.M (1999) Alimentary system: diseases of the stomach. In Colahan, P.T, Mayhew, I.G, Merritt, A.M, Moore, J.N Equine medicine and surgery, St Louis, Mosby, pp 699-715. In: Sanchez, L.C (2010) Other Disorders of the Stomach in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) Equine Internal Medicine (Third Edition), Saunders, Chapter 15.
  3. ↑ 3.0 3.1 3.2 3.3 Todhunter, R.J, Erb, H.N, Roth, L (1986) Gastric rupture in horses: a review of 54 cases. Equine Vet J, 30:344-348.
  4. ↑ 4.0 4.1 4.2 4.3 4.4 Merck & Co (2008) The Merck Veterinary Manual (Eighth Edition), Merial.
  5. ↑ 5.0 5.1 Kiper, M.L, Traub-Dargatz, J, Curtis, C.R (1990) Gastric rupture in horses: 50 cases (1979-1987), J Am Vet Med Assoc, 196:333-336. In: Sanchez, L.C (2010) Other Disorders of the Stomach in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) Equine Internal Medicine (Third Edition), Saunders, Chapter 15.
  6. ↑ Puotunen-Reinert, A, Huskamp, B (1986) Experimental duodenal obstruction in the horse. Vet Surg, 15:420-428. In: Sanchez, L.C (2010) Other Disorders of the Stomach in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) Equine Internal Medicine (Third Edition), Saunders, Chapter 15.
  7. ↑ 7.00 7.01 7.02 7.03 7.04 7.05 7.06 7.07 7.08 7.09 7.10 Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective. Equine Vet Educ, 6(4):178-184.
  8. ↑ Murray, M.J (1990) Gastric ulceration. In: Smith, B.P, Large Animal Internal Medicine, CV Mosby Publishing Company, USA, pp 648-652. In: Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective. Equine Vet Educ, 6(4):178-184.
  9. ↑ Clayton-Jones, D.G, Greatorex, J.C, Stockman, M.J.R, Harris, C.P.J (1972) Gastric impaction in a pony: Relief via laparotomy. Equine Vet J, 4:98-99. In: Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective. Equine Vet Educ, 6(4):178-184.
  10. ↑ Steenhaut, M, Vlaminck, K, Gasthuys, F (1986) Surgical repair of a partial gastric rupture in a horse. Equine Vet J, 18:331-332. In: Sanchez, L.C (2010) Other Disorders of the Stomach in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) Equine Internal Medicine (Third Edition), Saunders, Chapter 15.
  11. ↑ Hogan, P.M, Bramlage, L.R, Pierce, S.W (1995) Repair of a full-thickness gastric rupture in a horse. J Am Vet Med Assoc, 207:338-340. In: Sanchez, L.C (2010) Other Disorders of the Stomach in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) Equine Internal Medicine (Third Edition), Saunders, Chapter 15.
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