Vomiting Flashcards
T/F:
Vomiting is a reflex
TRUE
What are the 3 phases of vomiting?
Nausea (Prodromal) Phase
Retching Phase
Expulsion Phase
T/F:
The stomach is responsible for actively expelling contents
in vomiting
FALSE!
The force that expels is from the contraction of the
diaphragm and abdominal muscles
Stomach, esophagus, and sphincters are all
______ during vomiting
relaxed
Fill in the blanks for the pathway of vomiting:
Stimuli → Afferent pathways → Higher brain →
___________→ CRTZ →______→Efferent motor signals→ VOMIT
Stimuli→ Afferent pathways → Higher brain →
Vestibular Apparatus→CRTZ→Emetic Center→
Efferent motor signals→ VOMIT
Which receptors are found in the
Vestibular Nuclei?
H1, AChM
Which receptors are found in the
Visceral Afferents?
5-HT3
Which receptors are found in the
CRTZ?
D2
5-HT3
NK-1
Which receptors are found in the
Vomiting Center?
AChM
NK-1
Which receptor is found in the Stomach and SI?
NK-1
Where is the CRTZ located?
The medulla oblongata
The CRTZ is stimulated by the ________ system
vestibular
Motion Sickness is also known as
Kinetosis
Describe the mechanism of motion sickness:
_______ stimulation→ Dopamine and Serotonin released
from ______ activation→______ released from emetic center
Inner ear/labyrinth stimulation→ Dopamine and Serotonin released
from CRTZ activation→ACh released from emetic center
How do drugs like chemo agents stimulate vomiting?
5HT-serotonergic receptors and CRTZ
How does intestinal inflammation stimulate vomiting?
Direct afferent input to the vomiting center
How do opioids stimulate vomiting?
Stimulation of the CRTZ, increased vestibular sensitivity,
gastric stasis, or impaired intestinal motility/constipation
What are 3 ways that uremia can cause vomiting?
Decreased gastric clearance→ulcers,gastritis
Toxins cross BBB→stimulate central and peripheral receptors
D2-dopaminergic receptors→ activates CRTZ
Acute vomiting is <____week
Chronic is >_____week
Acute- < 1 week
Chronic- > 1 week
T/F:
A foreign body can cause either acute or chronic vomiting
TRUE!
chronic- ball moving in and out of the pylorus intermittently
Normosol
Plasmalyte
LRS
Sodium Chloride
Are all examples of this type of fluid
maintenance
Famotidine, Ranitidine, and Cimetidine
are all drugs in this category
used in the tx of vomiting
H2-receptor antagonists
What is the MOA of H2-receptor antagonists?
Affects gastric parietal cell receptors resulting in
reducing acid secretion with only a mild effect on pH