Vomiting

Question 1

What are the phases of vomiting

Answer 1

Nausea
Retching
Expulsion

Question 2

What happens during the retching phase of vomiting?

Answer 2

Abdominal muscles, chest wall and diaphragm contract without actually puking bc the duodenal contents are moving into the stomach
Deep inspiratory movements
Respiratory center is inhibited

Question 3

What happens during phase 3 of vomiting?

Answer 3

Forceful expulsion
Stomach does not actively expel
Stomach, esophagus, and sphincters relaxed during vomiting
Forge that expels arises from the contraction of the diaphragm and abdominal muscles

Question 4

What is the physiological pathway for vomiting?

Answer 4

Stimuli -> afferent pathways (sensory and central) higher brain vestibular apparatus CRTZ -> emetic center -> efferent motor signals = vomit

Question 5

Acute vomiting timeline

Question 6

Chronic vomiting timeline

Answer 6

> 1 week

Question 7

Does abdominal ultrasound take the place of X-rays?

Answer 7

Nope

Question 8

How do you tx acute vomiting and not ill?

Answer 8

Antacid +/- fluid therapy and time
Anti-nausea can suppress normal vomiting response to expel FB (don’t mask with meds)

Water and food- no water for 6-8 hours then small frequent amounts working back to normal over 24-48 hours

If no vomiting, small meals every 4-6 hours for day 1 with bland diet or prescription diet

Question 9

What are pantoprazole and omeprazole and how do they work?

Answer 9

Gastric proton pump inhibitor antacid
Inhibits transport of hydrogen ions into the stomach
Inhibits the hepatic cytochrome p450 mixed function oxidase system

Question 10

Why aren’t histamine antagonists helpful for cats

Answer 10

Bc cats don’t have histamine receptors on CRTZ

Question 11

How does metoclopramide work?

Answer 11

D2- dopaminergic antagonist (5-HT3 antagonist and 5-HT4 agonist)

Stimulus on movement of distal esophagus and is antiemetic

More effective in the cat than the dog

Question 12

What are Dolasetron (anzemet) and Ondansetron (zofran)

Answer 12

5-HT3-serotonin antagonists

Work in GI tract and CRTZ

Question 13

How does Cerenia work?

Answer 13

Competes with substance P peripherally and centrally

Question 14

How does sucralfate work?

Answer 14

Stimulates PG E2 and I1- cytoprotective 
Reacts w/ HCl to form past which sticks to ulcers 
Inactivated pepsin and binds bile acids 
Binds gastrointestinal phosphorus 
Weak antacid

Question 15

Name 4 pro kinetic drugs

Answer 15

Metoclopramide
Cisapride
Ranitidine
Erythromycin

Question 16

5-HT4 Receptor Activators (drugs and how they work)

Answer 16

Cisapride
Metoclopramide

Gastric emptying and GI motility
Stimulate release of ACh into the enteric no
LES, stomach, colon

Question 17

How does macrolide antibiotics work?

Answer 17

Stimulate motilin
Promotes intestinal motility
Initiates phase III of migrating myoelectric complex which propels ingesta

Drug- erythromycin

Question 18

How does cyproheptadine work?

Answer 18

appetitive stimulant
H1 receptor blocker
Serotonin antagonist

Question 19

How does mirtazaprine work?

Answer 19

Tetracyclic antidepressant
Increases NE and thus appetite
5-HT3 antagonist
H1- histamine antagonist