Vomiting, Acute

DEFINITION
Forceful, reflex expulsion of gastric contents from the oral cavity
Acute vomiting is defined as vomiting of short duration (<7 days) and variable frequency.
PATHOPHYSIOLOGY
A complex set of reflex activities under central neurologic control involving the coordination of GI, abdominal, and respiratory musculature
Often preceded by prodromal signs of nausea that can include depression, shivering, hiding or seeking comfort, hypersalivation, lip licking, frequent swallowing, and retching
Occurs when the VC in the medulla is stimulated by afferent activity from several sources
Stimulation can occur from stretch receptors, chemoreceptors, and osmoreceptors located throughout the GI tract, hepatobiliary system, genitourinary system, peritoneum, and pancreas.
The CTZ, when stimulated by a variety of drugs and toxins, can also stimulate the VC.
Higher centers can lead to psychogenic vomiting and input from the vestibular apparatus (e.g., motion sickness, vestibular disease) can stimulate the VC.