GERD Flashcards
True or false: gastric acid is the only troublesome contents that are regurgitated in GERD.
FALSE: while gastric acidity is an important factor in GERD pathophysiology, the activated digestive enzymes and the detergent bile acids contained in the duodenal contents will also be harmful.
True or false: the esophagus is not the only organ affected by GERD.
TRUE: while the main organ affected is the esophagus, extensive reflux can damage the vocal cords and respiratory airways
What is NERD?
Non Erosive Reflux Disease: which is GERD in the absence of pathologic evidence like esophagitis or inflammation
True or false: GERD is the most common outpatient GI diagnosis in the US
TRUE!
What are two factors in the US that are implicated for the rising incidence of GERD?
the extensive treatment of H. pylori and the current epidemic of obesit
True or false: if you have a smaller gastric volume, it is more likely that you will have GERD.
FALSE: the higher the gastric volume, the larger the refluxate
True or false: if you have higher pressure in the abdomen, it is more likely reflux will occur.
TRUE
What are the key agents in the stomach contents that lead to GERD?
Acid
Pepsin (proteolytic)
(synergistic)
Why is GERD worse in Zollinger-Ellison syndrome?
acid secretion is continuously stimulated by hypergastrinemia
Why does getting rid of H. pylori lead to an increased incidence of GERD?
because chronic H. pylori infection may ultimately result in gastric atrophy and decreased acid secretion
Which is more active in acid, conjugated or deconjugated bile salts?
conjugated
What duodenal contents can cause damage in GERD?
Bile salts (dissolve fats)
Amylase (polysaccharides)
Trypsin (proteins)
Lipase (lipids)
Why is it hard to detect duodenal reflux?
there is not good marker for it
Which part of the diaphragm forms a pinchcock around the entrance of the esophagus into the stomach?
crural diaphragm
What does the crural diaphragm do?
increases the lower esophageal pressure, especially during instances when an increased pressure gradient between the stomach and esophagus favors gastroesophageal reflux
What are two instances when the pressure gradient between the stomach and esophagus favors gastroesophageal reflux?
1) contraction of the inspiratory muscles of respiration produces negative intraesophageal pressure
2) contraction of the abdominal wall increases abdominal pressure
What is the name of the angulation where the fundus meets the esophagus that forms a flap valve that anatomically prevents reflux into the esophagus?
angle of His
What is the normal pressure gradient across the GE junction?
5-10 mm Hg
What is the resting pressure of the LES?
10-30 mm Hg
What happens when you swallow and propagation of an esophageal peristaltic wave occurs?
the LES relaxes to allow esophageal content and food to enter the stomach
What is it called when the ability of the LES to relax for food passage occurs?
achalasia (leads to dysphagia)
What are the two instances in which LES alterations lead to GERD?
hypotensive LES (uncommon) transient LES relaxation
What are some causes of hypotensive LES?
- Severe esophagitis
- Pregnancy
- Scleorderma
- Post ablative surgery (Heller myotomy)
- Fat, chocolate, peppermint and various medications
What is the cause of most reflux episodes in healthy patients?
transient LES relaxation (tLESR) which is accompanied by inhibition of the crural diaphragm
How long is the duration of tLESR?
greater than 10 seconds (longer than swallow-induced relaxation)
What stimulates tLESR?
- gastric distention (major, think of belching)
- stress, fat, and pharyngeal stimulation (minor)
Which is accompanied by a continuous repetitive “off contraction” throughout the esophageal body: tLESR or swallow-induced LESR?
tLESR
swallow-induced LESR is assoicated with a primary peristalsis
What is the condition where a widened diaphragmatic hiatus and a relaxed phreno-esophageal ligament allows the proximal stomach to migrate into the thorax?
hiatal hernia
List the three ways a hiatal hernia can lead to GERD.
- Loss of the diaphragmatic and abdominal pressure at the location of the hernia
- Loss of the angle of His and the accompanying flap valve
- Increased tLESR frequency
How do “sliding” and “rolling” hiatal hernias differ?
the “rolling” type of hiatal hernia is where the herniation is para-esophageal
What aids esophageal clearance of gastric acid?
esophageal peristalsis
What is the difference between primary and secondary peristalsis?
Primary peristalsis, initiated by saliva/a swallow, will propagate and strip the entire esophagus, while secondary peristalsis will start at the point of esophageal irritation and will clear the esophagus from that point onwards.
What is responsible for the neutralization of any remaining small amount of esophageal acid left in the esophagus?
bicarbonate contained in saliva and in secretions from submucosal esophageal glands
What is an anatomical protective factor against gastric acid reflux in the esophagus?
many layers of keratinized cells in the squamous esophageal mucosa
Why is GERD worse during sleep, with smoking, or with anticholinergics?
these are times of xerostomia (inhibited salivation), so there is less saliva to protect from the gastric acid
How does esophageal dysmotility cause GERD?
preventing efficient clearance of the esophagus
True or false: GERD is worse in a prone position.
What is the implication for this?
FALSE: GERD is worse in a supine position– the basis for the recommendation that patient with GERD should not lie down for 2 hours after a meal and should sleep with the head of the bed elevated
Why is GERD worse in patients with delayed gastric emptying?
the fuller the stomach is, the more these contents will be prone to reflux
Why do physicians tell patients with GERD to lose weight and not to wear tight clothes?
increased abdominal and intragastric pressure (e.g with obesity) will also induce reflux