Exam 3 - GI Part 1 Flashcards
Pathophysiology of GERD?
Retrograde movement of acid from the stomach into the esophagus; as well as bile acids, pancreatic enzymes, and pepsin.
Leads to increased contact of stomach acid with mucosa.
Caused by low LES tone, increased intra-abdominal pressure, gastric emptying, etc.
Where are gastric acids coming from?
Parietal cells secrete gastric acid.
H-K-ATPase secretes hydrogen ions and produces an acidic environment in stomach.
Influenced by histamine affecting H2 receptors, muscarinic receptors, acetylcholine to increase activity of proton pump.
Gastrin secretes more gastric acid.
Paracrine cells release histamine, which are affected by muscacrinic and gastric receptors.
What inhibits secretion of gastric acid?
NSAIDs inhibit production of prostaglandins, which means stomach isn’t as protected. Less acid will be secreted.
Epithelial cells function in stomach?
Responsible for protecting stomach.
Prostaglandins and muscarinic receptors increase release of bicarbonate for mucus.
Mucus layer on cells has pH of 7.
Gastric lumen can have a pH of 2.
Mucus protects gastric ulcers from being formed.
Risk factors for GERD
Obesity, delayed gastric emptying, pregnancy, hiatal hernias, recumbency (laying back), smoking, spicy food
What foods trigger GERD?
Alcohol, spicy food, citrus, tomatoes, fatty foods, chocolate, and peppermint
Medications that trigger GERD?
Anticholinergics, narcotics, CCBs
Anything that prevents the smooth muscle from contracting and slows peristalsis.
NSAIDs cause GERD by inhibiting prostaglandin synthesis.
What is bisphosphate?
Used for osteoporosis, but can stick in the throat and lead to GERD.
Complications of GERD
Esophagitis, strictures, anemia from bleeding, Barrett Esophagus, risks for cancer from long-standing reflux.
Clinical Presentations of Esophageal Symptoms
Heartburn (pyrosis), followed by regurgitation, belching, and water brash (hyper salivation).
Atypical signs of GERD
Pharyngitis, chronic cough horaseness
What are alarming signs of GERD that should be taken care of in ER?
Continual pain, dysphagia, odynophagia, unexplained weight loss, GI bleeding, choking, and vommitting.
Esophagus is bright red from coughing, or GI bleed = black tarry stools.
LIfestyle modifications for GERD
LIfestyle modifications - don’t eat spicy foods, don’t smoke, weight loss, elevate head of bed, avoid alcohol
Pharmacology intervention and therapy is possible.
How do you treat kids with reflex?
Surgery can pull stomach muscle over esophageal sphincter to help close it for kids with bad reflux.
Acid-Peptic Disease
Roles of therapy?
Neutralize excess acid, decrease gastric secretion, or enhance gastric mucous defense.
What meds help neutralize excess acid?
Antacids - directly neutralize acid in the stomach; best to take in the morning before you eat or afterward when you have symptoms to neutralize (Time when most acid is produced).
Different palatability of GERD meds?
Some meds respond better than others
Types of antacids
Sodium bicarbonate
Calcium carbonate
Aluminum Hydroxide
Magnesium Hydroxide
How does sodium bicarbonate work?
Not super common. Quickly neutralizes acid and produces sodium and alkali load.
Can see fluid retention, because of added sodium. May not be good for salt sensitive. Can also produce gas.
Raises pH of stomach (base), so stomach thinks it needs to produce more acid and have more gastrin release. May need more antacid to counteract. Limited in use.
Calcium Carbonate (Tums)
Works rapidly, moderate neutralizing ability, and will absorb calcium.
If they have kidney stones or kidney issues with too much calcium, can exacerbate.
Taking calcium orally can cause constipation.
Chelates other drugs.
Aluminum Hydroxide (Amphagel)
Good phosphate binder. Used for patients with chronic kidney disease and hyperphosphatemia.
May see decreased stomach emptying (might increase gastric acid secretion). Forms a cytoprotective effect on mucosa to help with natural barrier.
Will cause constipation.
Have the ability to chelate other drugs - Need to separate antacids from other drugs by taking it an hour before or 4 hours afterwards. Like Bile Acid Sequestrants.
Why do you separate levofloxacin and ciprofloxacin from GERD medicines?
They can bind calcium and magnesium! Take an hour before or four afterward.
Magnesium hydroxide (Milk of Magnesia)
“Green Rocket”
Good neutralizing ability; see magnesium chloride has low solubility, can have some Mg absorption through tract.
Can cause diarrhea; used for constipation!
Bad for appendicitis, intestinal obstruction, AND renal failure, because you don’t want them to absorb magnesium (Hypermagnesiuma).
MgOH + AlOH (Mylanta, Maalox) - Comes in a liquid suspension. Coats GI tract. Can counteract GI motility.
Problems with antacid treatment at home?
They can mask worsening disease, because they don’t know the alarming signs.
Safe in pregnancy, but AVOID sodium bicarbonate - more prone to HTN.