WikiVet English - User contributions [en]

Colic, Medical Treatment

2010-09-19T15:04:16Z

Nmr28:

{{unfinished}}

Colic should always be viewed as an emergency as almost every colic case starts with a medical aspect. Over 90% of colics are medical and of these, the majority are associated with spasmodic intestinal colic. It can be difficult for veterianarians to distinguish between medical colic and an early surgical colic because the clinical signs are often very similar. It is often a lack of response to medical therapy that makes the decision. If referral is necessary then it should be done as soon as possible as a slow approach by the veterinarian will result in time delay and incorrect therapy and a poor outcome.

Medical colic is defined as colic that will respond to drug therapy and management alone. Once treated, cases of medical colic should not have any further complications that could have been avoided hd surgery been undertaken. Medical colic is a common condition in equine practice. It can be potentially life threatening so referral centres still play a role in the mnagement of medical coic. Some cases may also be contagious and/or zoonotic. The differentiation between [[Colic, Decision Making|medical and surgical]] colics is critical and can be acheived by a thorough clinical examination. There are important considerations to keep in mind when interpreting colic clinical signs. Some horses and especially donkeys and zebras, are very stoical in their nature and show only mild clinical signs, despite having a serious surgical condtion. Some horses have a low pain threshold and so may show severe, unrelenting signs of colic that are features of surgical colic cases. Medical causes of colic are often less painful than surgical causes. However, anterior enteritis can cause extreme pain, but can be managed medically with Metronidazole, penicillin, analgesia and repeated [[Nasogastric intubation in the horse|gastric decompression]]. Few medical cases have a complete abscence of borboygmi. The faecal output can also provide valuable information. Cases with diarhoea are often medical in nature and require medical management. Cases with a reduced faecal output for a couple of days usually have an impaction of the large colon. Very hard, mucous covered faeces indicate a reduced transit time through the small colon. This could be due to [[Grass Sickness]].

Pain management is an important aspect of treating any colic patient, whether it be surgical or medical. There are two major types of pain; visceral pain and parietal pain. Visceral pain is associated with inflammation or distention of a viscus, tension on the mesentery or a reduction in the blood supply. It is an obvious pain and the horse will exhibit [[Colic Diagnosis - Clinical Signs|signs of abdominal discomfort]]. The pain is oftern persistent and the horse maybehave violently if the pain is severe. Severe, unrelenting pain despite the administration of analgesia is an indication for surgery. Spasmodic colic that responds to analgesia is most likely to me medical. Parietal pain is associated with inflammation of the serosal surfaces of the organs of the peritoneum and parietal peritoneum. This pain is less obvious and the horse may be immobile guard the abdomen. This type of pain features in cases with a ruptured viscus and secondary peritonitis.

The response to mild analgesia is ofteen used to determine the level of pain and decide whether the case is medical or surgical. Mild analgesics include phenylbutazone or hyoscine-n-butyl bromide (Buscopan). Cases that do not respond within 2 hours require reassessment and potentially referral. Stong analgesics such as flunixin should not be used until the diagnosis has been made as many early surgical cases can be misdiagnosed as medical colics.

Treatment for the colicking horse should include all of the following:
* Pain relief
* Stabilization of the cardiovascular and metabolic status
* Minimizing the effects of endotoxaemia
* Establishing a functional intestine

Therapies should include the following, where clinically indicated:
* Analgesia
* Fluid therapy
* Cardiovascular support
* Laxatives and cathartics
* Antiendotoxin therapy
* Treatment for ischaemia-reperfusion injury
* Antimicrobial therapy
* Nutritional support
* Surgical intervention

===Analgesia===
Analgesia can be accomplished by the use gastric dcompression and the administration of analgesics.

====Nasogastric decompression====
Some patients require an indwelling nasogastric tube and repeated refluxing every 2 hours to prevent gastric distension and possibly gastric rupture. Patients referred to a surgical facility will require an indwelling nasogastric tube whilst being
transported.

====Non-Steroidal Anti-Inflammatory Drugs====
=====Flunixin meglumine=====
===Fluid Therapy and Cardiovascular Support===

===Laxatives===

===Antiendotoxin Therapy===

===Treatment for Ischaemia-Reperfusion Injury===

===Antimicrobials===

===Nutrition===
Management of medical colic should also inlude diet management. All food including hay and straw bedding should be withheld until the resolution of the condition. The normal diet can then be re-introduced slowly over 1-2 days beginning with a moist bran and alfalfa pellet mash, then grazing grass, followed by moist hay and finally grain. If the patient does not have continuous gastric reflux then ad lib water and a trace mineral salt lick should be provided. If there is any doubt regarding the diagnosis and exploratory surgery is a possibility then all food should be withheld during transport to the referral facility.

===Surgical Intervention===
The decision to treat the patient surgically or medically depends on a number of [[Colic, Decision Making|criteria]]. Most colic cases seen in first opinion practice are mild and respond well to medical management. A small proportion of cases will require surgery and a lack of response to medical therapy is often the deciding factor. Candidates who are dificult to categorise should be referred early as procrastination and time delay during transportation could worsen the prognosis of the patient. A ventral midline celiotomy is the surgical approach for most cases but specific treatments for specific disorders also apply.

Large colon impactions can be difficult to manage.Most cases will respond to aggressive medical treatment with analgesics, laxatives, oral and intravenous fluid therapy. Some may not respond to medical therapy and are secondary to another lesion, such as a concurrent large colon displacement or impaction of the right dorsal colon, which may only be resolved with surgery.

[[Category:Medical_Colic_in_the_Horse]]

Gastric Dilation and Rupture - Horse

2010-08-11T19:55:22Z

Nmr28: /* References */

{{unfinished}}

{| cellpadding="10" cellspacing="0" border="1"
| Also known as:
|'''Gastric Rupture'''
|}

{| cellpadding="10" cellspacing="0" border="1"
| See also:
|'''[[Colic, Gastric Causes]]'''
|}

==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>

==Aetiology==

*'''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>

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

==Clinical signs==
'''Gastric dilation''' usually produces:
*Acute, severe [[Colic Diagnosis - Clinical Signs|colic]]
*Tachycardia
*Pale mucous membranes
*Retching<ref name="Merck">Merck & Co (2008) '''The Merck Veterinary Manual (Eighth Edition)''', ''Merial''.</ref>
*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<ref>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.</ref>). Furthermore, '''nasogastric intubation does not preclude the possibility of 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>'''''

'''Gastric rupture''' typically results in:
*Relief
*Depression
The inevitable '''peritonitis''' and '''endotoxic shock''' will lead to:
*Reluctance to move<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>
*Tachypnoea
*Tachycardia
*Sweating
*Muscle fasciculations
*Blue or purple mucous membranes<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: 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.''<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>

==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>

'''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>

'''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
*White cell count >40 x 109/l
*Protein content >30g/l.
Findings on [[Colic Diagnosis - Rectal Examination|rectal examination]] may include<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 '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.
[[Colic Diagnosis - Clinicopathologic Evaluation|Laboratory findings]]<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> may include:
*Haemoconcentration
*Hypokalaemia
*Hypochloraemia

==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>

*'''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. Other approaches for gastric impaction are described [[Gastric Impaction - Horse|elsewhere.]] 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==
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]].

==References==
<references/>

[[Category:To_Do_-_Nina]]
[[Category:To_Do_-_Review]]
[[Category:Surgical_Colic_in_the_Horse]]

2010-08-11T18:29:03Z

Nmr28:

Abnormalities involving the descending (small) colon are infrequent, accounting for <5% of conditions characterized by colic in one study. The more common causes include meconium retention, impaction, and foreign body obstruction. (Merck)

[[Small Colon Impaction - Horse|Small colon impaction]]

[[Meconium Impaction - Horse|Meconium retention]]
=====Pelvic masses=====
A persistent mild colic may be found when intra-pelvic masses impinge upon the gastro-intestinal tract. Most commonly these are haematomas. Peri-anal lesions, such as [[melanomas]] may also produce these signs.

=====Neurological deficits=====
A complete or partial paralysis of the small colon and rectum may occur with [[polyneuritis equi]], resulting in a lack of faecal expulsion, and consequent obstruction. A diagnosis is made via a neurological examination. Treatment is palliative only, although the condition can be managed for many years by manual emptying of the rectum.

[[Category:Medical_Colic_in_the_Horse]]
[[Category:To_Do_-_Nina]]

Colic, Small Colon Causes

2010-08-11T18:28:54Z

Nmr28:

Abnormalities involving the descending (small) colon are infrequent, accounting for <5% of conditions characterized by colic in one study. The more common causes include meconium retention, impaction, and foreign body obstruction. (Merck)

[[Small Colon Impaction - Horse|Small colon impaction]]
[[Meconium Impaction - Horse|Meconium retention]]
=====Pelvic masses=====
A persistent mild colic may be found when intra-pelvic masses impinge upon the gastro-intestinal tract. Most commonly these are haematomas. Peri-anal lesions, such as [[melanomas]] may also produce these signs.

=====Neurological deficits=====
A complete or partial paralysis of the small colon and rectum may occur with [[polyneuritis equi]], resulting in a lack of faecal expulsion, and consequent obstruction. A diagnosis is made via a neurological examination. Treatment is palliative only, although the condition can be managed for many years by manual emptying of the rectum.

[[Category:Medical_Colic_in_the_Horse]]
[[Category:To_Do_-_Nina]]