Gastrointestinal Disease Moodle Book Flashcards
Dysphagia
defined as difficulty swallowing food and is usually detected at an early stage as it is relatively easily noticed by the owner.
Dysphagia may be classed as
Functional- where there is an underlying problem with the physical mechanics of swallowing, this may due to an underlying neuromuscular disorder affecting the physiological conduction of the swallowing reflex. In some cases functional dysphagia may be of unknown cause.
Dysphagia may be classed as;
Morphological- where problems in the anatomical structures of the oral or pharyngeal cavities result in difficulty swallowing. This can arise where a patient has severe dental disease or other condtions causing infection and inflammation of the oral and pharyngeal cavities, where trauma has damaged the tissues or where a neoplastic lesion (tumour) has formed.
Signs of dysphagia
dropping food from the mouth
excessive salivation
coughing
reluctance to eat
gagging
excessive motion of the head/head shaking
Diagnosis of Dysphagia
Diagnosis is based on history taking and clinical examination of the patient and may require further testing such as biopsy, culture and radiography to establish an underlying cause.
Treatment of Dysphagia
Treatments are based on addressing the underlying cause and providing symptomatic therapy (for example analgesia and amended constituency of food/assisted feeding if required).
Vomiting
an active process where gastric (and potentially dudodenal) content that is usually partly digested is forcibly ejected from the stomach
abdominal muscles strain during the process of vomiting
often occurs several hours after eating
if severe can be associated with loss of electrolytes and dehydration
Regurgitation
a passive process where mainly undigested food is returned from the oesophagus
there is no active contraction of the abdominal muscles
usually occurs shortly after eating
Regurgitation is generally a sign of oesophageal disease
Characteristics of regurgitation include
passive explusion of undigested food
occuring shortly after eating
patient may be anorexic or ravenous depending on the underlying pathology
may lead to pneumonia due to aspiration of food material
may eventually lead to cachexia - loss of body mass
Characteristics of vomiting include the forcible nature by which ingesta is expelled from the mouth.
Clinical signs may include;
nausea and salivation which may be accompanied by restlessness
retching and active abdominal effort
production of digested or semi-digested food or bile
possible anorexia, polydipsia and dehydration
depending on the underlying cause the content of the vomit may vary and the nature of the vomiting episodes may be acute or chronic.
Causes of vomiting may be classed as ;
PRIMARY - originating from the gastro intestinal tract. Examples include;
dietary indiscretion
infectious disease
GDV
inflammatory GI disease
foreign bodies
neoplasia
pyloric stenosis
poisoning
intussusception
endoparasites
Causes of vomiting may be classed as primary, for example -
dietary indiscretion
infectious disease
GDV
inflammatory GI disease
foreign bodies
neoplasia
pyloric stenosis
poisoning
intussusception
endoparasites
Causes of vomiting secondary
These could include examples such as;
hepatic failure
renal failure
severe infection eg. pyometra
diabetes mellitus
pancreatitis
drug reactions
motion sickness
Secondary causes of vomiting are causes…
SECONDARYcauses of vomiting are conditions elsewhere in the body that lead to activation of the ‘vomiting centres’ in the brain.
Primary causes of vomiting are causes…
PRIMARY - originating from the gastro intestinal tract.
Diagnosis and treatment of vomiting
History and presenting clinical signs particularly if there is known ingestion of a toxic or inappropriate substance.
A full physical examination including abdominal palpation may provide some clues as to the underlying cause in many cases.
In addition further diagnostics such as radiography (possibly with contrast media), ultrasound or endoscopy may be utilised.
In addition analysis of blood and vomit/urine/faeces may be required particularly if systemic causes of poisoning is suspected.
In some cases an exploratory laparotomy may be necessary to obtain a definitive diagnosis
Treatment of the vomiting patient invariably includes treatment of the primary underlying cause of disease, a short period of gastric rest , use of anti-emetics and/or gastro protectants and fluid therapy to correct any dehydration or electrolyte imbalance.
Diarrhoea
The term diarrhoea is used to refer to the frequent discharge of abnormally soft or liquid faecal matter.
Diarrhoea, like vomting, may be classified according to the origin of the problem. Primary causes are …
Seconary causes are …
those that directly affect the GI tract whereas
secondary causes are systemic in nature.
Primary Acute diarrhoea-
Infection – viral (e.g. Parvovirus) or bacterial (e.g. Salmonellosis)
Giardiasis
Dietary Indiscretion
Primary Chronic diarrhoea
Endoparasites
Inflammatory Bowel Disease
Neoplasia
Colitis
Secondary diarrhoea
Addison’s disease
Renal failure
Pancreatic disease
Liver disease
There are several methods available to diagnose cases of diarrhoea…
History and clinical signs which may suggest an aetiology
Clinical examination and abdominal palpation
Radiography (+/- contrast) used to identify lesions within the GI tract
Endoscopy/biopsy may be required to obtain samples from the intestinal wall for definitive diagnosis
Faecal analysis often used to determine presence of parasite eggs, viral or bacterial pathogens
Treatment of diarrhoea
Treatment of diarrhoea will consist of specific treatments if an underlying cause has been identified (this could include worming of the patient, antibiotics where indicated, or treatments for renal or hepatic disease) combined with more non-specific symptomatic treatments such as….
Anti-diarrhoealsor drugs to reduce gastrointestinal motility
Absorbantdrugs to decrease faecal water content.
Anti-inflammatorieswhere colitis or IBD has been identified
Pro-Bioticsto support normal intestinal flora
Constipation can be due to either ….
the nature and content of the faecal matter making the process more difficult. Examples include scavenging and feeding inappropriate substances, particularly bones, low residue diets, foreign bodies, hairballs and dehydration
OR
structural problems leading to problems with the mechanics of defaecation. Examples include pelvic/hind limb fractures, rectal strictures, perineal hernia, enlarged prostate, megacolon, neoplasia, anal sac disease or neurological dysfunction
Clinical signs of constipation
Clinical signs may include;
Absence of defaecation
Tenesmus or straining to pass faeces
Dyschezia or pain on defaecation
Haemochezia or passage of fresh blood with the stool
Discomfort, pain
If severe may affect appetite
Diagnosis and treatment of constipation
Diagnosis
—History and clinical signs
—Physical examination
—Radiography
—Colonoscopy
Treatment
—Treat the cause
—Diet
—Stool-softening agents
- Removal of impacted material
Cirrhosis
is the term used to describe fibrosis of the liver tissue that occurs as a result of degenerative changes to the tissue
Jaundice
Jaundiceis the yellow pigmentation of skin and mucous membranes often observed in patients suffering from liver disease. It is caused by an increase is serum levels of bilirubin.
Pre-hepatic jaudice
caused by haemolysis of red blood cells causing increased circulating bilirubin. This may be seen in patients with immune mediated haemolytic anaemias, those who have received an incompatible blood transfusion or in certain blood borne infections.
Hepatic jaundice
where the liver itself does not function correctly. There are various causes and they may be acute or chronic in nature
Examples of hepatic causes of jaundice include….
Infectious, e.g. ICH, leptospirosis
Genetic, e.g. copper toxicity in Bedlington terriers
Metabolic e.g. lipidosis
Toxic insults
Immune mediated hepatitis
Primary neoplasia affecting the liver tissue
Post-hepatic jaundice
where a disease of lesion elsewhere prevents the liver secreting bile
Post-hepatic jaundice examples,
Examples include;
—Gall bladder disease e.g. Gall stones, cholangitis
—Pancreatitis
—Intestinal obstruction
Diagnosis of liver disease
History and clinical signs- patients with liver disease may exhibit signs such as anorexia, weight loss and ascites as well as jaundice depending on the severity of their condition. Hepatic encephalopathy - nervous signs related to high blood ammonia levels may be seen in advanced cases of cases of PSS (see later) Additional signs related to reduced production of bile acids and plasma proteins may occur such as passing of pale faeces or clotting disorders.
Physical examinationmay reveal hepatomegaly.
Blood biochemistry- liver profile may be undertaken measuring liver enzymes such as alkaline phosphatase (ALKP) and alanine aminotransferase (ALT) and assessing bile acid function and plasma protein levels
Imaging- radiography or ultrasonography may be used to determine liver size or presence of lesions
Liver biopsy- to obtain a definitive diagnosis
PSS - portosystemic shunt
A portosystemic shunt is most often observed as a congenital condition in which the presence of a ‘shunting vessel’diverts blood from the small intestines directly to the venous system bypassing the liver.This means that the liver cannot then process the products of digestion leading to build up of toxins and proteins in the blood and reduced liver function.