Clinical Approach to Vomiting (Winston)

Question 1

(T/F) Vomiting is a diagnosis as well as a clinical sign

Answer 1

False, vomiting is a clinical sign, not a diagnosis

Question 2

Vomiting is a _______________ reflex

Answer 2

central nervous system

Question 3

(T/F) Coordinated closure of nasopharynx and glottis to protect the airway

Answer 3

True

Question 4

Definition:
Is used when vomitus contains blood flecks, blood clots, or brown coffee ground-like material (digested blood)

Answer 4

Hematemesis
(serious problem)

Question 5

Acute vomiting: _____ week in duration

Answer 5

< 1

Question 6

Chronic vomiting: _______ week in duration

Answer 6

> 2-3

Question 7

Causes of vomiting can be characterized as:

Answer 7

1. Primary gastrointestinal (GI)
2. Extra-GI/Systemic disorders

Question 8

List GI Causes of ACUTE Vomiting:

Answer 8

• Dietary Related
• Acute gastritis or enteritis
• Drug-induced
• Viral enteritis
• Bacterial infection
• Parasites
• Gastric or intestinal obstruction

Question 9

(T/F) It is okay to not look under a cat’s mouth that presents for vomiting

Answer 9

False, you need to complete oropharyngeal examination in every vomiting cat to look for a string wrapped around the base of the tongue

Question 10

List Extra-GI Causes of ACUTE Vomiting:

Answer 10

• Motion sickness
• Vestibular disease
• Acute pancreatitis
• Acute kidney failure
• Acute hepatic failure
• Ketoacidotic diabetes mellitus
• Pyometra
• Prostatitis
• Peritonitis
• Drug-induced (e.g., cardiac glycosides, narcotics, chemotherapeutics)
• Sepsis
• CNS disorders (inflammation, edema)

Question 11

What is necessary to rule out extra-GI disorders that cause vomiting prior to evaluating for primary GI disorders with contrast radiology, endoscopy, or exploratory laparotomy?

Answer 11

Laboratory Evaluations

Question 12

The top extra-GI causes of vomiting (+/- diarrhea) are:
- Liver Failure
- Pancreatitis
- Kidney Failure
- HYPOadrenocorticism
But for cats, we need to add on…

Answer 12

• Hyperthyroidism
• Heartworm disease

Question 13

Many vomiting animals do not have an acid-base disturbance but if they do, it is more commonly a ______________due to severe dehydration → poor tissue perfusion → subsequent lactic acidosis

Answer 13

metabolic acidosis
- LRS or plasmalyte (likely with additional KCl)

Question 14

_____________________ is most likely to occur in dogs and cats with vomiting secondary to pyloric or proximal small bowel obstruction. Can also occur 2º to severe diffuse vomiting w/o obstruction

Answer 14

Metabolic alkalosis
- 0.9% saline supplemented with KCl

Question 15

(T/F) If vomiting is severe or persistent enough to require antiemetics, you should also be simultaneously investigating the underlying cause

Answer 15

True

Question 16

If the owner reports that the patient re-ingest the “vomitus”, consider _______________ and not ________________

Answer 16

regurgitation, vomiting

Question 17

Stimulation of the afferent nerves in the ___________________ can be caused by diseases that result in inflammation, irritation, infection, or stretch of organs within the abdominal cavity

Answer 17

abdominal viscera

Question 18

Stimulation of the _____________________ zone can be caused by noxious substances in the bloodstream that typically arises from either an organ-system failure, blood-borne toxin, or drug-induced

Answer 18

chemoreceptor trigger

Question 19

Stimulation of the __________________ is primarily caused by motion sickness or disease of cranial nerve VIII

Answer 19

vestibular apparatus

Question 20

Stimulation of the _________________ is medicated by psycho-social cues (e.g. stress) in people and will not be further considered here as a cause of vomiting in dogs and cats

Answer 20

cerebral cortex

Question 21

___________________ is a good general-use anti-emetic in cats. In dogs, however, it is most effective for inhibiting abdominal visceral (and NOT chemoreceptor trigger zone) causes of vomiting

Answer 21

Ondansetron (Zofran)

Question 22

___________________ works well in dogs to inhibit the chemoreceptor trigger zone causes of vomiting. In cats, however, it is NOT thought to inhibit any inputs to the vomiting center and instead functions as a prokinetic (promotes gastrointestinal motility).

Answer 22

Metoclopramide (Reglan)

Question 23

Four drugs are used most commonly in dogs and cats for the control of vomiting, which one is this one?

• blocks dopamine (D2) receptors

Answer 23

Metoclopramide (Reglan)
- Chemoreceptor Trigger Zone (dogs)

Question 24

Four drugs are used most commonly in dogs and cats for the control of vomiting, which one is this one?

• blocks serotonin (5-HT3) receptors

Answer 24

Ondansetron (Zofran)
- Abdominal Viscera (dog)
- Vomiting Center (cats)

Question 25

Four drugs are used most commonly in dogs and cats for the control of vomiting, which one is this one?

• blocks neurokinin (NK1) receptors (substance P)

Answer 25

Maropitant (Cerenia)
- all of them both cats and dogs (Abd. Viscera, Chemo.trigger zone, Vestibular apparatus, vomiting center)

Question 26

Four drugs are used most commonly in dogs and cats for the control of vomiting, which one is this one?

• blocks alpha-adrenergic (alpha1/alpha2) receptors (also blocks dopamine, histamine type-1 & muscarinic receptors

Answer 26

Chlorpromazine (Compazine)
- Chemoreceptor Trigger Zone (dogs & cats)
- Vomiting Center (dogs & cats)