GI - SA acute vomiting/diarrhoea Flashcards
Where is the vomiting centre located?
In the brainstem
What parts of the body act on the vomiting centre?
Cerebral cortex
Vestibular system
GI tract
Peripheral sensory receptors
Chemical stimuli in blood
What are the 4 stages of vomiting?
Prodromal - signs of nausea
Retching
Expulsion
Relaxation
What are the signs of nausea?
Restlessness
Lip smacking
Salivating
What occurs during retching?
Duodenal retroperistalsis
What occurs during expulsion of vomit?
Pyloric contraction
Lower oesophageal sphincter relaxation
Protect the airway - breathing inhibition, closed glottis
Abdominal contraction
Diaphragm descent - squashes stomach
What are some bad consequences of vomiting?
Fluid loss - dehydration
Acid base disturbance
Aspiration pneumonia
What make up normal stomach electrolytes?
Hydrochloric acid and potassium
(HCl only produced during feeding though)
What makes up normal duodenum electrolytes?
Bicarbonate
What electrolytes are primarily lost during vomiting with a patent pylorus? What does this cause?
Primarily lose bicarbonate and potassium
Causes a metabolic acidosis
Why does vomiting with a patent pylorus cause a metabolic acidosis?
Because the only thing left is the HCl making it acidic
What electrolytes are primarily lost during vomiting with an obstructed pylorus? What does this cause?
Primarily lose hydrochloric acid and potassium (the stomach contents)
Causes a metabolic alkalosis
What are the main two anti-emetic drugs?
Maropitant
Metoclopramide
What action does maropitant have to act as an anti-emetic?
NK1 receptor antagonist
What are the actions of metoclopramide?
Anti-emetic
Pro-kinetic - stimulates gastric and duodenal motility
When should you not use metoclopramide?
If there is a GI tract blockage - increased motility doesnt help
In cats - poor efficacy, maropitant is better
What are the 4 disease types of diarrhoea?
Osmotic
Secretory
Permeability
Motility
What causes osmotic diarrhoea?
Food not being digested properly
Net water movement into gut lumen due to the unabsorbed solute
What causes secretory diarrhoea?
Intestines secrete too much GI fluid and cant absorb it back
What causes permeability diarrhoea?
Disease in the lining of the intestines
Increases the leakiness and impairs fluid absorption, villus atrophy
What causes motility diarrhoea?
Increased GI transit rate - pass through too quickly for fluid to be absorbed
What is motility diarrhoea usually secondary to?
Bacterial toxins
Intestinal distention (laxatives)
High T4
What can be used/done as therapy for diarrhoea?
Appropriate fluid intake
Buscopan - antimuscarinic
Opioids
What should you do to treat acute diarrhoea?
Usually self limiting so doesnt need treating itself, just treat symptoms eg. fluid balance
Do obstructions cause vomiting or diarrhoea?
Vomiting
Does stomach/small intestinal disease cause vomiting or diarrhoea?
Can cause both
Does large intestinal disease cause vomiting or diarrhoea?
Diarrhoea
What is the term for small intestinal inflammation?
Enteritis
What is the term for large intestinal inflammation?
Colitis
What is the difference between a primary and extra GI disease?
Primary - structural or functional disease which primarily affects the GI tract
Extra - disease elsewhere in the body which affects GI health or function
What should you investigate first - primary or extra GI disease?
Extra GI disease - because they are easy to miss if you investigate the primary GI causes first
Unless the history makes it very obvious that it is a primary GI disease eg known foreign body
What is the difference between acute and chronic vomiting/diarrhoea?
Chronic - more than 3 weeks duration
Acute - less than 3 weeks, usually less than 1 week
What are the causes of acute vomiting/diarrhoea out of the VITAMIND list?
Vascular
Inflammatory
Traumatic/toxic
What are some primary GI inflammatory causes of acute vomiting/diarrhoea?
Parvovirus
Parasites
Bacterial enteritis
What are some extra GI inflammatory causes of acute vomiting/diarrhoea?
Acute pancreatitis
Infection eg. pyometra, hepatitis, peritonitis
Hypoadrenocorticism
What can cause chronic vomiting/diarrhoea out of the VITAMIND list?
Inflammatory, neoplastic
Metabolic
What are some primary GI inflammatory causes of chronic vomiting/diarrhoea?
Chronic inflammatory enteropathies
eg. food responsive disease, antibiotic responsive disease, inflammatory bowel disease
What are some extra GI inflammatory causes of chronic vomiting/diarrhoea?
Chronic pancreatitis
What are some metabolic causes of chronic vomiting/diarrhoea?
Exocrine pancreatic insufficiency
Endocrine disease
Renal disease
Hepatic disease
What is the difference between small and large intestinal diarrhoea?
SI - large volume, normal frequency, no urgency
LI - small volume, increased frequency, with urgency, straining and difficulty, may have more mucus
What are some other signs of small intestinal disease other than diarrhoea?
Weight loss
Inappetence or pica, polyphagia, coprophagia
Gas production
What will a puddle of diarrhoea from small intestinal disease look like?
Large brown liquid puddle
What will a puddle of diarrhoea from small intestinal disease look like?
Smaller bloody, mucousy puddle
When should acute vomiting/diarrhoea be investigated?
If dehydrated/hypovolaemic
If there was an abnormality/alarm bell from history or clinical exam
What should you do to manage acute vomiting/diarrhoea?
Fluids
Bland food little and often
Not very good to fast them
Anti-emetic (if obstruction excluded)
Appetite stimulant
Analgesia (NOT NSAIDs)
Probiotics
What is the difference between prebiotics and probiotics?
Prebiotics - feed and promote the health of the bacteria in the gut
Probiotics - the microorganisms themselves
Should you give antimicrobials if vomiting/diarrhoea?
NO - unless know that it is bacterial enterocolitis which is rare
What should you do if you suspect a GI foreign body?
Abdominal radiographs
Emesis if small/soft
Surgical resection - if obstructed/perforated
Wait and see - if small/not obstructed/needle
When should you do faecal analysis?
If have done all the tests eg. haem, biochem, imaging and still not found an answer
What can you test for on faecal analysis?
Parvovirus
Parasitology
Giardia
Tritrichomonas
What are the 3 diseases that it might be if vomiting/diarrhoea cause is not found after haem, biochem, imaging or faecal testing?
Acute pancreatitis
Hypoadrenocorticism
Hyperthyroidism
What is the job of the exocrine tissue in the pancreas?
Produce digestive enzymes for proteins, carbs and fats
Produce NaHCO3/bicarbonate to neutralise gastric acid
What is the job of the endocrine tissue in the pancreas?
Produce insulin and glucagon
What are the digestive enzymes in the pancreas stored in?
Zymogen granules (away from the activators that are stored in lysosomes)
What happens in pancreatic pathology?
Abnormal fusion of zymogen granules and lysosomes causing pancreatic autodigestion
What can trigger pancreatitis?
Dietary indiscretion - high fat items
Obesity
Blunt abdominal trauma
Hypoperfusion
Drugs
Idiopathic
What breed is predisposed to pancreatitis?
Miniature schnausers
Where is the pancreas located?
Left limb - adjacent to duodenum
Right limb - adjacent to transverse colon
Adjacent to common bile duct
Near stomach
What are the presenting clinical signs of pancreatitis?
Vomiting
Diarrhoea
Inappetance
Abdominal pain (prayer position)
Pyrexia
Jaundice
How does pancreatitis cause vomiting?
Duodenum proximity causes inflammation and ilius
Stomach proximity causes peritonitis/inflammation, vagal nerve stimulation
How does pancreatitis cause jaundice?
Pancreas swelling can block bile duct
What is the difference between acute and chronic pancreatitis?
Sudden onset vs waxing/waning
potentially fully reversible vs progressive
What can chronic pancreatitis result in if it gets to end stage?
Exocrine pancreatic insufficiency
Diabetes mellitus
What can you see on biochem/haem to indicate pancreatitis?
Inflammatory leukogram - neutrophilia, left shift
Acute phase protein response - hyperalbuminaemia and hyperglobulinaemia
What is the test of choice for pancreatitis?
Pancreatic lipase immunoreactivity
What are the two types of pancreatic lipase immunoreactivity tests?
Spec cPL/fPL - quantitative, monoclonal antibodies sent to lab
SNAP test - qualitative, lots of false positives
How do you interpret a SNAP pancreatic lipase immunoreactivity test?
Test spot lighter than reference - negative
Test spot same as or darker than reference - may be positive, send off for spec
What does pancreatitis look like on ultrasound?
More abnormal on acute than chronic
Abnormal size/echogenicity
Free fluid
What does pancreatitis look like on radiograph?
Loss of detail in right cranial quadrant - local peritonitis
Poor sensitivity
How do you manage acute pancreatitis?
Supportive
Fluids
Nutrition - keep feeding little and often
Control nausea, vomiting, pain
What is the prognosis of acute pancreatitis?
Guarded - recurrence and death possible
Can develop exocrine pancreatic insufficiency
How is canine parvovirus spread?
Faeco-oral spread - low infective dose
What disinfectants can you use to inactivate canine parvovirus?
Formalin
Hypochlorite
What is an issue with canine parvovirus vaccination?
Maternally derived antibody causes an immunity gap where this wanes but not responsive to vaccination yet
What is the usual signalment of canine parvovirus?
Variable but usually unvaccinated puppy around 3-6 months old
What are the main clinical signs of canine parvovirus?
Haemorrhagic diarrhoea - intestinal crypt necrosis
Dehydrated
Neutropenia - bone marrow necrosis
+/- vomiting
How do you diagnose canine parvovirus?
Faecal parvovirus antigen ELISA (in house) - test any dog with haemorrhagic diarrhoea
PCR - lab test cheek swab
How do you treat canine parvovirus?
Aggressive fluid therapy
Nasoesophageal tube trickle feeding once stopped vomiting
May need glucose supplementation
Antiemetic
Antibiotic - amoxyclav
How can you administer aggressive fluid therapy for canine parvovirus dogs?
IV
Intraosseus
When should you give antibiotics in canine parvovirus cases? What antibiotic do you give?
IF severe Haemorrhagic diarrhoea
And/or neutropenic
Amoxycillin clavulanate
How do you prevent canine parvovirus?
Vaccination
Barrier nursing
Disinfection with hypochlorite
What is the prognosis of canine parvovirus?
Variable
>50% fatality if no care provided
What are the different names for feline parvovirus?
Feline panleukopenia
Feline infectious enteritis
How does feline parvovirus relate to canine parvovirus?
Closely related virus
Same clinical syndrome
Can transmit from dogs to cats and vice versa
What can feline parvovirus cause in kittens?
Cerebellar hypoplasia
What signalment are particularly at risk of getting bacterial enterocolitis?
Raw fed diet
Young
Unsanitary/crowded environment
What pathogens cause bacterial enterocolitis and how is this an issue?
E. coli
Clostridium perfringens
Campylobacter
Salmonella
Can all be isolated from healthy dog faeces too - often overdiagnosed
What are the clinical signs of bacterial enterocolitis?
Haemorrhagic vomiting and/or diarrhoea
Pyrexia
Sepsis
Enterotoxaemia
How do you test for bacterial enterocolitis?
Faecal culture - only if have the right clinical signs and are at risk animals
What campylobacter species is related to disease in dogs?
C. jejuni
What campylobacter species is related to disease in cats?
C. coli
What campylobacter species is a commensal in dogs?
C. upsaliensis
What disease does campylobacter have the potential of developing?
Potential to attach/invade and cause ulcerative enterocolitis
What antimicrobial is the first line therapy for campylobacter GI infection?
Erythromycin
What can antibiotics do in cases of salmonella?
May encourage carrier state
When should you treat salmonella?
Only if clinically unwell - subclinical carriage is common in healthy animals (30% of dogs)
How do you subtype clostridium perfringens?
Subtype based on various toxins
What symptoms do dogs with clostridium perfringens tend to have?
Large intestinal diarrhoea
But can have small or mixed as well
How do you diagnose and treat clostridium perfringens?
Faecal culture - but huge limitations
Only treat if systemically ill
Ampicillin or metronidazole
What causes Acute Haemorrhagic Diarrhoea Syndrome (AHDS)?
Thought to be clostridium perfringens NetF toxin targeting pore in enterocytes
What are the clinical signs of Acute Haemorrhagic Diarrhoea Syndrome (AHDS)?
Acute haemorrhagic diarrhoea
Marked haemoconcentration (less fluid in blood)
+/- vomiting
Hypovolaemia
What does Acute Haemorrhagic Diarrhoea Syndrome (AHDS) diarrhoea look like?
Strawberry jam
How do you diagnose Acute Haemorrhagic Diarrhoea Syndrome (AHDS)?
Consistent clinical sings
Marked elevation in PCV without protein increase
How do you treat Acute Haemorrhagic Diarrhoea Syndrome (AHDS)?
Intravenous crystalloid fluid therapy - boluses and continuous rate infusion
Amoxyclav if pyrexic/sepsis
When does disease from clostridium difficile tend to occur?
Disease likely secondary to toxin production
How do you diagnose clostridium difficile?
Faecal culture or ELISA antigen test
How do you treat clostridium difficile?
Metronidazole
When should you consider a bacterial pathogen is causing gastrointestinal disease?
ACUTE haemorrhagic vomiting/diarrhoea
With pyrexia
Sepsis
Inflammatory leukogram
What signalment do roundworms cause GI signs in?
Puppies/kittens
What are the names of the roundworms?
Toxocara canis
Toxocara cati
Toxascaris leonina
How do puppies/kittens contract roundworms?
Transplacental
Transmammary - drink in milk
What are the clinical signs of roundworms?
Vomiting/diarrhoea
Bloated abdomen
Obstruction if high amounts
How do you diagnose roundworms?
See adults in faeces
Faecal parasitology - eggs
What is a big risk of roundworms?
Zoonotic - causes larva migrans in humans
What are the names of the hookworms?
Ancylostoma
Uncinaria
What do ancylostoma hookworms cause?
GI blood loss
Anaemia
Iron deficiency
How do uncinaria hookworms invade?
Enter through the digital skin of the paws
What do uncinaria hookworms cause?
Pedal pruritus
Diarrhoea
How do you treat ancylostoma hookworms?
Pyrantel
What is the whipworm called?
Trichuris
What do whipworms cause?
Large intestinal diarrhoea - live in caecal and colonic mucosa, bury tail causing inflammation
GI blood loss
Abdominal pain
What do tapeworms cause?
DONT tend to cause GI signs
What are the main protozoa affecting the GI tract?
Giardia
Tritrichomonas
Cryptosporidium
What species does giardia affect?
More common in dogs than cats
Zoonotic - humans
What does giardia cause?
Acute or chronic diarrhoea
Malabsorption, weight loss
How do you diagnose giardia?
Faecal analysis - fresh smear
Antigen ELISA
Zinc sulfate floatation - oocysts
What doe giardia look like on fresh smear?
Pear shaped
Motile
Move like a falling leaf (different to tritrichomonas)
How do you treat giardia?
Fenbendazole orally once daily for 3 days
Clean environment, treat all dogs in household
What does tritrichomonas foetus cause?
Chronic recurrent large intestinal diarrhoea
Can be asymptomatic
Peri-anal oedema
Faecal incontinence
What signalment does tritrichomonas affect?
Kittens and young cats - immunity at maturity
How do you test for tritrichomonas?
Colonic wash - PCR
How do you treat tritrichomonas?
Ronidazole once a day for 2 weeks
Isolate
