Gastrointestinal Motility Flashcards
(25 cards)
sub-threshold slow waves
produce a weak contraction
slow waves depolarize
much stronger or phasic contractions
serotonin
- activates sensory neurons
- activates myenteric plexus.
substance P and ACh
contraction
NO, VIP, neuropeptide y, ATP
relaxation
Migrating Motor Complex (MMC)
Sweeps the stomach & small intestine of indigestible materials in preparation for the next meal
Loss of the MMC
can cause bacterial overgrowth in the small intestine
Esophagus transit time
10 seconds
Stomach transit time
1-3 hours
Small Intestine transit time
7-9 hours
Large Intestine transit time
25-30 hours
GASTRO-ESOPHAGEAL REFLUX DISEASE (GERD)
LES is incompetent
Associated with tobacco, alcohol, scleroderma
Presentation: heartburn, sour taste, dysphagia, regurgitation
Complications: Barret’s esophagus
Barret’s esophagus
stratified squamous epithelium is replaced by intestinal simple columnar epithelium with goblet cells
Complication: adenocarcinoma of the lower esophagus
Achalasia Cardia
degeneration ofAuerbach’s (myenteric) plexus in the DISTAL ESOPHAGUS
“bird’s beak” appearance
*** Migrating motility complexes (MMC) occur about every 90 min between meals and are thought to be stimulated by the gastrointestinal hormone, motilin. An absence of MMCs causes an increase in which of the following?
Intestinal bacteria
*** A 68-year-old male presents to his primary care physician with complaints of heartburn, belching, and epigastric pain. He states that the symptoms are aggravated by drinking coffee or eating fatty foods and improved by taking chewable heartburn relievers. He is started on a trial of omeprazole, which relieves his discomfort for several weeks, but his symptoms return. When counseling this patient, which of the following statements must be made?
He is at increased risk of esophageal cancer and should have further tests
Mallory-Weiss tear
Superficial longitudinal mucosal lacerations
Boerhaave’s syndrome
full-thickness rupture of the distal thoracic esophagus
complication ofbulimia
*** A 21-year-old male presents to the emergency department with hematemesis. He had been out drinking every night that week with his friends in celebration of his 21st birthday. He reports having vomited each night, but tonight when he started vomiting, his friends noticed that there was streaking of blood and brought him into the emergency department. An upper endoscopy is conducted and reveals superficial lacerations of the distal esophagus as shown in the figure. Which of the following abnormalities is associated with this patient’s presenting condition?
Mallory-Weiss tear
*** A 20-year-old female presents to the hospital with severe chest pain. She states that the pain started suddenly and is retrosternal in nature. The pain began shortly after lunch and is worse with swallowing. She has no prior medical history except for a brief inpatient stay for what she describes as an “eating disorder.” On exam, her vitals are as follows: HR 120, RR 22, BP 145/90. She is flushed and taking deep breaths. Which of the following abnormalities is associated with this patient’s presenting condition?
Boerhaave’s syndrome
Gastric emptying time faster with
Liquid contents
Isotonic contents
Gastric emptying time slower with
Fatty acids
H+ ions
Hypertonic or hypotonic contents
GASTROPARESIS
damage to the vagus nerve
*** A 48-year-old female visits your office complaining that she has trouble swallowing solids and liquids, has persistent bad breath, and sometimes wakes up with food on her pillow. Manometry studies show an absence of functional peristalsis and a failure of the lower esophageal sphincter to collapse upon swallowing. The patient’s disorder is associated with damage to which of the following?
Myenteric (Auerbach’s) plexus
Achalasia Cardia
