Vomiting In Dogs and Cats Flashcards
What is the prodromal phase of vomiting?
Prodromal phase:
- nausea (??) –doesn’t always progress into vomiting!
- hypersalivation
- loss of appetite
- lip licking
- excessive swallowing
What happens during the retching phase of vomiting?
Retching:
- retrograde duodenal contractions
- rhythmic inspiratory movements against a closed glottis
- dilation of the cardia and the lower oesophageal sphincter
What happens during the expulsion phase of vomiting?
Expulsion: -abdominal muscles involved
- reduced oesophageal and pharyngeal tone
- active expulsion of gastric/duodenal contents by contraction of abdominal muscles
When does aspiration become a risk with vomiting?
- If weakpatient or neurological compromise, the fine tuning of this pathway isn’t as good as it should be and these patients can be at risk of aspiration –this is why vomiting through alcohol toxicity is so risky and dangerous, because there are compromised reflexes and more likely to aspirate
What are some peripheral nervous system triggers for vomiting?
Abdominal visceral receptors - stretching of GI, inflammatory etc
GI tract, biliar system, peritoneum
What are some things that can activate the CRTZ and therefore vomiting?
What are some diet causes that can cause vomiting?
- Change of diet
- planned
- unplanned
- Spoiled food
- Food intolerance
- non immune mediated
- Food allergy
- IS immune mediated process
- types I, III and IV
- proteins (glycoproteins)
What are some stomach conditions that can cause vomiting?
- Inflammatory
- “gastritis” (acute or chronic)
- ulceration
- Physical
- foreign body
- outflow obstruction
- hiatal hernia
- Functional
- motility disorder
- Neoplastic
- adenocarcinoma
- Lymphoma – always possible in cats
- Leiomyoma
What are some intestinal causes of vomiting?
- Inflammatory
- inflammatory bowel disease (IBD)
- infectious enteritis/colitis
- SIBO/ARD
- Physical
- foreign body
- Intussusception
- Can often palpate this is puppies and kittens easily
- volvulus (mesenteric torsion) –hugely rare.
- constipation? Potentially can be a cause of vomiting if very severe but unlikely to be the only thing the owner will tell you about
- Intestinal disease is just as likely to cause vomiting as gastric disease. Intestinal disease can obviously cause diarrhoea and/or weight loss as well but don’t forget vomiting is a major clinical sign of intestinal disease.
- SIBO: small intestinal bacterial overgrowth
- ARD: antibiotic responsive diarrhoea
What are some functional intestinal causes of vomiting?
Functional
- Ileus
- Vomiting causes hypokalaemia which leads to poor motility
- Constipation?
What are some intestinal neoplastic causes of vomiting?
Neoplastic
- carcinoma
- lymphoma
- focal
- Generalised throughout GI just causing generalised thickening in gut wall (Cats!)
- leiomyoma/sarcoma
- Cancers of muscle wall
- Intestinal mast cell tumour (cats)
What are some general abdominal causes of vomiting?
- Pancreas (examples only!)
- acute or chronic pancreatitis
- pancreatic tumour
- EPI with SIBO?
- Peritonitis
- Liver disease (examples only!)
- cholangiohepatitis
- chronic hepatitis
- cholecystitis
- biliary obstruction +/-rupture
- Renal disease
- CKD/acute kidney injury
- pyelonephritis
- urinary tract obstruction
- calculi
- blood clots
- tumours
- Uterine
- Pyometra –likely cause of vomiting
- Pregnancy –less likely, but due to stretch receptors activated in the abdomen
- Prostatic disease –anything painful or inflammatory here can activate CRTZ
- prostatitis
- paraprostaticcysts
- prostatic tumour
- benign hyperplasia?
What are some viral causes of vomiting (and d+ in most cases)?
- Parvovirus, Feline panleucopenia
- Coronavirus (FIP), FeLV/FIV
- Distemper, Canine adenovirus (ICH),
- Others –rotavirus, enterovirus, astrovirus
What are some metabolic/endocrine causes of vomiting?
- Hyperthyroidism
- cats (not dogs)
- Azotaemia
- Hypoadrenocorticism
- Diabetic ketoacidosis
- Hypercalcaemia
- Hepatic encephalopathy
- congenital PSS?
- acquired liver disease
- Vomiting likely to be one of the clinical signs in these cases, often other clinical signs to go with it
What are some bacterial causes of vomiting (and d+ in most cases)?
Salmonella
Clostridium perfringens
E.coli
Campylobacter jejuni
Yersinia
What are some top tips with regards to bacterial and viral causes of vomiting?
- Think about signalment and vaccination status of the patient
- Why are infectious diseases more likely in puppies and kittens? More likely to succumbtoviralinfections, butalsoaged immunosuppressed animals Causes of vomiting (and diarrhoea in most cases…)
What are some parasitic causes of vomiting?
- Parasites?
- worms
- Toxocara
- Taenia
- Uncinaria
- Trichuris
- Dipylydium?
- protozoa –often pop up in puppies and kittens, might have multiple reasons for vomiting as the gut has not yet learnt how to get rid of these organisms
- Isospora
- Cryptosporidium
- Giardia
- Tritrichomonas (cat)
- worms
Usually infection can be a cause of vomiting, but it isnt all too serious as it is treatable.
When is it a serious cause of vomiting?
When it becomes septicaemia
What are some toxin causes of vomiting?
Toxins (examples only!)
- ethylene glycol
- raisins or grapes (dogs)
- theobromine
- heavy metal/lead
- daffodils, ivy, bluebells, lilies
- conkers & acorns
- amanita phalloides
- adder bites & toads
- luminous necklaces
- Often there will be other important clinical signs and hopefully a useful history in these cases
What are some iatrogenic causes of vomiting?
Drugs (examples only!)
- antibiotics
- NSAIDs
- cyclosporine
- cytotoxics
- Digoxin
- Some vomiting associated with drugs (eg antibiotic associated vomiting) is an individual patient side effect, some (eg cyclosporine) can be common in most patients.
- Owner may be giving drugs or medication that they think is harmless, but may not be a great thing to do –need a history to help with this
What are some central/CNS causes of vomiting?
Central/CNS
- motion sickness
- Usually young animal thing
- vestibular disease
- Idiopathic –can just present with vomiting and owners don’t always notice the tell tale signs
- Often elderly patients, need to think about managing and support at the difficult times
- encephalitis
- limbic epilepsy
- tumours
- Odd things cats do
- congestive heart failure -> vomiting, anorexia
- Airway disease Causes of vomiting
What are some indications for inducing vomiting?
- Gastric decontamination after toxin ingestion
- within 4-6 hours
- ideally ASAP, <2-3hrs
- +/-gastric lavage
- +/-activated charcoal
- Foreign body ingestion
What are some contraindications for inducing vomiting?
- Caustic substance ingestion
- Lethargy/debilitation
- Dyspnoea
- Neurological signs
- Abdominal surgery
- Spinal injury
What is a dopamine agonist used to induce vomiting in dogs?
Apomorphine
Name 2 alpha 2 agonists that are used to induce vomiting in cats?
Medetomidine
Xylazine
What are plans for investigating acute or chronic vomiting in patients?
Signalment
Full clinical history
Thorough physical exam
What are some more likely causes in younger dogs for acute/chronic vomiting?
Foreign body
Dietary indiscretion
Infectious disease
Intussuception
What are some more likely causes in growing up dogs for acute/chronic vomiting?
IBD
Diet Intolerance
What are some more likely causes in older dogs for acute/chronic vomiting?
Neoplastic diseases more common
What are some more likely causes in older cats for acute/chronic vomiting?
Hyperthyroid
Lymphoma
If you have oral dysphagia and there is a problem with prehension, what are some likely causes?
Oral injury
Dental Disease
Oral FB/mass
Cranial Nerve Problem
Masticatory muscle disease
Mandible fracture
If you have pharyngeal dysphagia and there is a problem with swallowing, what are some likely causes?
Cranial nerve problem
Cricopharyngeal achalasia
FB/mass in pharynx
Rabies??
What is ptyalism?
Hypersalivation
What are some things that can cause ptyalism that is unrelated to nausea?
Oropharyngeal disease
Protosystemic shunt
Salivary gland disease - sialadenitis, phenobarb responsive sialadenitis
What are some important points in patient assessment with every patient, every time?
- Clinical history:
- why is the patient at the vets?
- what are the owners concerns?
- what have they seen?
- Physical exam:
- is your patient sick or well ?
- what are your findings
- Collate & interpret the information using your knowledge and experience
- Come up with a plan which might be:
- diagnostic
- therapeutic
- both running in tandem
When is it okay NOT to worry about the dog or cats vomiting?
When your patient is
- bright and alert
- clinically well
- appropriately hydrated
- showing short duration clinical signs
- If owners aren’t worried and just need reassurance
If we have decided to only give supportive care, what are some things we can do?
- Anti emetics?
- Gut protectants? Recent review on these has reminded us how little evidence we have to say these things work
- 24 hrs stave
- water little & often
- electrolyte fluids?
- Bland, easy to digest diet initially
- high protein
- low fat
- small meals
If you have only given supportive care to a vomiting patient, how soon should you check up on them?
If no better or worse in 24 hours: CALL OR REVISIT
When should we do basic investigations into a vomiting patient?
When your patient is
- quite bright but lacking stamina
- “fades” during consult
- borderline dehydrated
- dry/tacky mm
- nauseous
- salivating
- lip smacking
- PCV/TP +/-blood smear
- blood glucose
- electrolytes (Na/K)
- urea and creatinine
- urine SG and stix
- store baseline samples especially if:
- treatment indicated
- fluid therapy
When should you definitely worry about your vomiting patient?
History:
- several days duration or rapid deterioration
- persistent vomiting and/or inappetence
- “not keeping anything down”
- “not interested in any food”
- haematemesis
- blood?
- Looks like coffee grounds?
- profuse SI diarrhoea
- Rapid weight loss or any weight loss
Physical Exam
- weak, collapsed
- MM: dry/tacky, pale or congested
- tachycardia, bradycardia, arrhythmia
- weak & threadyor hyperdynamic pulses
- Check the metatarsal pulses!
- hypothermia or pyrexia
- abdominal pain or distension
- melaena, haemorrhagic diarrhoea
What are some screening tests we can use for the vomiting patient if we need to?
Blood tests
- haematology/CBC
- numbers & blood smear
- biochemistry
- electrolytes
Urinalysis
- dipstick
- specific gravity
- sediment examination
- +/-culture
- When you might want to use radiography and when you might want to use ultrasound. US is useful for looking at enlarge or abnormal LNs –if looking for lymphoma or FB reaction into LNs etc. abnormal LN can alert you to a more severe process
When is one instance of using ultrasound a good screening test for a vomiting patient?
When you might want to use radiography and when you might want to use ultrasound. US is useful for looking at enlarge or abnormal LNs –if looking for lymphoma or FB reaction into LNs etc. abnormal LN can alert you to a more severe process
When is endoscopy indicated?
When is it not appropriate?
Indicated for chronic disease
Not appropriate for acute disease unless confirming a gastric ulcer (although we often treat symptomatically) or removing a FB
What is shown here?
Giardia
What are some diagnostic investigations for critical cases?
- Blood gas analysis?
- Lactate?
- Peritoneal fluid sampling?
- Exploratory surgery?
- take (plenty of) biopsies –even if you find nothing! As you went in for a reason! If you cant find a FB, take biopsies of a lot of the organs –get as much info as possible to make time worthwhile
What is the supportive care and stabilisation for management of vomiting?
Fluid therapy
- how much?
- how fast?
- which fluid?
Electrolyte replacement?
- Anti emetics
- if no obstruction?
- can monitor closely
- avoid with toxin ingestion initially
- if no obstruction?
Gastroprotectants-frequently used but poor evidence behind this –not as useful as we think
- misoprostol-no justification and possSEs
- Sucralfate –commonly used, does no harm?
- others: aluminium hydroxide, bismuth
Prokinetics
- ranitidine?
Nutrition
- can be problematic
Care of the hospitalised patient
- think about what needs to be on the kennel sheet
Name some gastroprotectans sometimes used for the management of stabilisation
Misoprostol
Sucralfate
Aluminimum hydroxide
Bismuth
What is the ideal anti emetic drug like?
- Broad spectrum activity vs vomiting centre
- central & peripheral pathways
- Minimal cardiovascular side effects
- patients may be
- dehydrated
- haemodynamically unstable
- patients may be
- Wide therapeutic index
- clearance mechanisms may be compromised
- renal
- hepatic
- clearance mechanisms may be compromised
- Minimal CNS side effects (such as sedation)
- reduces risks of aspiration
- increases ability to
- diagnose 1ry disease
- assess progression of 1ry disease
- Minimal –ve effects on GI motility
- reduces risk of
- gastric stasis
- ileus
- constipation
- reduces risk of
What kind of effects do you want an anti-emetic to have on the CNS?
Minimal CNS side effects (such as sedation)
- reduces risks of aspiration
- increases ability to
- diagnose 1ry disease
- assess progression of 1ry disease
What kind of effects do you want an anti-emetic to have on the GI motility?
Minimal –ve effects on GI motility
- reduces risk of
- gastric stasis
- ileus
- constipation
Maropitant is an anti-emetic drug.
Where does it work?
What is it effective against?
Which species and how is it given?
- selective NK1 receptor antagonist
- effective against
- peripheral pathways
- central pathways
- higher dose required for motion sickness
- useful prophylactic?
- useful analgesic properties? Might be useful for things such as pancreatitis
- cats & dogs
- oral & injectable
Metaclopramide is an anti-emetic drug.
Where does it work?
Where does it have its effects?
Which species and how is it given?
- dopamine, 5-HT 3 & H 1 receptor antagonist
- central>peripheral pathway effects
- variable prokineticeffect
- cats & dogs
- oral & injectable
Explain the vomiting reflex - what are the centers?
- Two separate centres
- CRTZ
- chemical stimuli
- BBB is permeable in the area of the CRTZ
- vomiting centre in brainstem
- coordinates and integrates vomiting
- Vestibular apparatus
- input for motion sickness
- CRTZ
Explain the pathophysioloy of vomiting
- The vomiting centre consists of several brain stem nuclei
- receives nerve impulses via 2 pathways
- central
- peripheral
- +/-input from vestibular system in motion sickness
- receives nerve impulses via 2 pathways
- Substance P
- neurotransmitter
- binds to NK-1 receptors
- NK-1 receptors
- location: cell membrane
- vomiting centre
- CRTZ
- Substance P binds (“lock & key”) to NK-1 receptor
- Generated signal transmitted via vagus nerve
- Stimulates vomiting via abdominal muscles & diaphragm
