GI WORKSHOPS Flashcards
what does GORD stand for?
gastro oesophageal reflux disease
(sometimes refered to as GERD)
What is Gastro oesophageal reflux disease?
- Gastro-oesophageal reflux is the retrograde, effortless movement of stomach contents into the oesophagus.
- When troublesome symptoms or mucosal damage occurs as a result of this process, this is defined as gastrooesophageal reflux disease (GORD)
diagnosis of GORD
- diagnosis of GORD is **suggested when heartburn or regurgitation symptoms occur two or more times per week **
- Endoscopy is preferred for assessing mucosal injury and to identify complications such as esophageal strictures (which can cause difficulty swallowing) and erosive esophagitis due to repeated and prolonged exposure to gastric refluxate.
- A mucosal biopsy should be taken to identify Barrett esophagus, which is associated with an increased risk of developing esophageal cancer
*
Clinical presentation of GORD (typical symptoms)
may be aggravated by activities that worsen reflux such as recumbent position, bending over, or eating a high-fat meal
* heartburn - often described as a substernal sensation of burning
* hypersalivation
* regurgitation
* belching
atypical symptoms of GORD
these are associate with GORD, but causality should only be considered if typical symptoms are also present
* chronic cough
* larngitis
* hoaresness
* wheezing
* noncardiac chest pain
* asthma (approx. 50% with asthma have GORD)
alarm symptoms of GORD
may indicate GORD complications such as Barrett esophagus, esophageal strictures, or esophageal adenocarcinoma and require further diagnostic evaluation
* dysphagia
* odynophagia
* weight loss
* bleeding
General approach to treatment of GORD
treatment for GERD involves one or more of the following modalities:
1. patient-specific lifestyle changes (non pharmacological therapy)
2. pharmacologic intervention primarily with acid-suppressing therapy
3. **antireflux surgery ** (surgical treatment)
Nonpharmacologic therapy for GORD
lifestyle modifications
* many won’t respond adequately to just lifestyle changes alone - it is still helpful to reduce need for long-term pharmacologic therapies
* losing weight if overweight or obese (particulary a reduction in waist circumference)
* elevating head of the bed with a foam wedge if symptoms are worse when recumbent
* smaller meals & avoiding meals 3h before sleeping
* avoiding food or medications that exacerbate GORD
* smoking cessation
* avoiding alcohol
why is elevating the head of the bed a helpful lifestyle modification for patients with GORD
decreases the contact time of gastric acid with the oesophageal mucosa at night
Surgical treatment of GORD
generally last resort BUT antireflux surgical options may be considered when there is a large hiatal hernia, evidence of aspiration or cardia dysfunction, or when pharmacologic management is undesirable due to side effects or adherence challenges in patients with well-documented GORD
* GOAL OF SURGERY → to reestablish the antireflux barrier, position the LES within the abdomen where it is under positive (intra-abdominal) pressure, and close any associated hiatal defect.
pharmacological therapies for treatment of GORD
Pharmacologic therapies for GERD typically involve **increasing the pH of gastric contents **through either direct gastric acid neutralization OR reducing acid production through inhibition of stimulation pathways, thereby reducing GERD symptoms and tissue damage.
* antacids & alginic acid
* histamine-2 receptor antagonists (H₂RAs)
* proton pump inhibitors (PPIs)
Effectiveness ranking of pharmacologic therapies for GORD
antacids are inferior to histamine-2 receptor antagonists (H2RAs), and H2RAs decrease acid secretion less than PPIs.
i.e. PPIs are best!
antacids & alginic acid for treatment of GORD
ANTACIDS:
* useful for intermittent treatment of GORD symptoms and can be used for patients with infrequent typical reflux symptoms
* effective for immediate, symptomatic relief, BUT require frequent dosing
* usually well tolerated, and potential side effects include constipation or diarrhea depending on the formulation being used
ALGINIC ACID:
* creates a viscous barrier that can aid in acid neutralization & is often used in combo with antacids
histamine-2 receptor antagonists for the treatment of GORD
- examples → cimetidine, famotidine, nizatidine
- decrease acid secretion by blocking histamine-2-receptors in gastric paretial cells
- provide relief from typical acute GERD symptoms and can also be administered prophylatically (as prevention treatment)
- more effective than antacids at controlling chronic GERD symptoms but less effective than PPIs
- may be dosed intermittently or on a scheduled basis depending on the degree of symptom control
- generally well tolerated; side effects are mild and include headache and nausea
Proton pump inhibitors (PPIs) for the treatment of GORD
- eg → omeprazole, lansoprazole
- block gastric acid secretion by inhibiting gastric H+/K+-ATPase in gastric parietal cells
- Primary uses of PPIs are treating frequent reflux symptoms and healing of gastric or esophageal ulcerations
- PPIs provide significant reduction in gastric acid and the greatest relief of symptoms, especially in patients with moderate-to-severe GERD, with high rates of healing erosive disease
- typically formulated in delayed-release capsules or tablets
- Most patients should be instructed to take their PPI in the morning, 30 to 60 minutes before breakfast to maximize efficacy.
- Due to their slow onset of action, PPIs are most effective when taken on a scheduled basis. Patients requiring a second dose if nighttime symptoms are predominant should take the dose before the evening meal
- PPIs are generally well tolerated; the most common side effects are headache and GI effects such as diarrhea and nausea
what is heartburn?
- common term to describe a burning feeling in the chest or throat caused by stomach acid.
- This feeling is a symptom of a condition, not a condition itself
what is gastric/acid reflux?
- common term to describe the movement of stomach acid up the oesophagus
- used interchangeably with GORD sometimes
what is dyspepsia?
- A term to represent a group of symptoms of upper GI discomfort including: bloating, belching, nausea, early satiety after meals. Symptoms usually associated with eating.
- also known as/called indigestion
what is emesis?
- the clinical word for vomiting
what is nausea?
unpleasant sensation of an urge to vomit
GI or intraperitoneal causes of vomiting
- obstructing disorders
- achalasia
- enteric infections
- appendicitis
- pancreatitis
- inflammatory bowel disease (IBS)
- cholecystitis
- gastroparesis
- gastroesophageal reflux (GORD)
- peptic ulcer disease
- peritonitis
cardiac causes of nausea & vomiting
- cardiomyopathy
- myocardial infarction
- heart failure
neurologic causes of nausea & vomitting
- vestibular disease
- motion sickness
- labryinthitis
- head trauma
- migraine headache
- increased intercranial pressure
- meningitis
- hydrocephalus
- psychological distress
- self-induced
- depression
other causes of nausea & vomiting
- bulimia
- anorexia nervosa
- cyclic vomiting syndrome
therapy induced causes of nausea & vomiting
- cancer chemotherapy
- antibiotics
- antiarrythmics
- digoxin
- oral hypoglycemics
- oral contraceptives
- theophylline
- anticonvulsants
- radiation therapy
- ethanol
- toxins
endocrine/metabolic causes of nausea & vomiting
- pregnancy (NVP)
- hyperemesis gravidarum
- renal disease (uremia)
- diabetes (ketoacidosis)
- thyroid disease
- parathyroid disease
- adrenal insufficiency
- hyponatremia
- hypercalcemia
what are common causes of acute nausea & vomiting
- infection
- motion sickness
- alcohol
- poisioning
- anaesthesia
- over-eating
- pregnancy
what are common causes of chronic nausea & vomiting
(these can also be causes of acute)
- migraine
- severe pain
- emotional distress
- gastroparesis
- traumatic brain injury/concussion
- food intolerance
- vertigo
- drug-induced
what are the most likely causes of vomiting in a young child?
the most common cause of vomiting in both adults & children is gastroenteritis, which is commonly known as ‘gastro’ or tummy bug
other causes include:
- food allergy
- poisoning
- reflux
- meningitis
- overeating
- stress
what is the most important (possible) medical complication associated with vomiting to manage in the short term?
dehydration
manage by rehydrating!
desired outcomes of treatment for nausea & vomiting
- The primary goals of treatment → relieve the symptoms of nausea and vomiting,** increase quality of life**, and prevent complications such as dehydration or malnutrition
- Drug therapy for nausea and vomiting should be safe, effective, and economical.
nonpharmacologic therapy for nausea & vomiting
- include dietary, physical, and psychological measures
- Dietary management is important when treating NVP due to concern for teratogenic effects with drug therapies
- eating frequent, small meals
- avoiding spicy or fatty foods
- eating high-protein snacks
- avoiding iron-containing pills
- eating bland or dry foods the first thing in the morning
signs of nausea and vomiting
with complex & prolonged nausea & vomiting, patients may show signs of malnourishment, weight loss, & dehydration (dry mucous membranes, skin tenting, tachycardia, & lack of axillary moisture)
laboratory tests for nausea & vomiting
Dehydration, electrolyte imbalances, and acid–base disturbances may be evident in complex and prolonged nausea and vomiting.
* Dehydration is suggested by elevated blood urea nitrogen (BUN), serum creatinine (SCr), and BUN-to-SCr ratio (20:1 or greater using traditional units of measurement [100:1 or greater using SI units of mmol/L]).
* Calculated fractional excretion of sodium (FeNa) less than 1% (0.01) indicates dehydration and reduced renal perfusion.
* Low serum chloride and elevated serum bicarbonate levels indicate metabolic alkalosis.
* Hypokalemia may occur from GI potassium losses and intracellular potassium shifts to compensate for alkalosis.
what are antimetic drugs, and what are the most common classes?
antimemetic drugs = drugs effective against nausea & vommiting
* anticholinergics
* dopamine antagonists
* corticosteriods
* cannabinoids
* benzodiazepines
* serotonin antagonists
* neurokinin-1 receptor antagonists
* olanzapine
anticholinergics (scopolamine) for nausea & vomiting
- scopolamine blocks muscarinic receptors
- effective for prevention & treatment of motion sickness, & some efficacy in preventing PONV
- adhesive transdermal (TD) patch, effective for up to 72 hours after application
- should be applied 4 hours prior to motion sickness triggers and the evening before surgery if used to prevent PONV
what does PONV stand for
Post-operative nausea & vomiting
what does CINV stand for
chemotherapy induced nausea & vomiting
antihistamines for nausea & vomiting
- used to prevent and treat nausea and vomiting due to motion sickness, vertigo, or migraine headache
- 2nd Gen → cyclizine, fexofenadine
- 1st Gen → meclizine, hydroxyzine, dimenhydrinate
- First-generation antihistamines cause undesired effects including drowsiness, blurred vision, and urinary retention
- available in a variety of dosage forms, including oral capsules, tablets, and liquids
what are the 3 main groups of dopamine antagonists (antiemetic drugs)
- phenothiazines
- butyrophenones
- prokinetic agents
phenothiazines for nausea & vomiting
- dopamine antagonist
- e.g. promethazine, prochlorperazine, chloropromazine
- Availability in multiple dosage forms (ie, oral, parenteral, rectal)
- use in a variety of settings including severe motion sickness or vertigo, gastritis or gastroenteritis, NVP, PONV, and CINV
what does NPV stand for
nausea & vomiting in pregnancy
butyrophenones in nausea & vomiting
- dopamine antagonist
- e.g. droperidol, haloperidol
- effective for preventing PONV
- may also be used in for treating CINV for patients who are intolerant to serotonin receptor antagonists and corticosteroids
- RARE BUT SERIOUS: QT prolongation, cardiac arrymthimias
Prokinetic agents in nausea & vomiting
- dopamine antagonists
- e,g, metoclopramide & domperidone
- Their antiemetic and prokinetic effects are useful in PONV, CINV, gastroparesis, and gastroesophageal reflux disease (GORD)
- Metoclopramide is available in injectable, oral solid, and oral liquid dosage forms
- metoclopramide crosses BBB, so has centrally mediated adverse effects!
corticosteriods for nausea & vomitting
- e.g. dexamethasone, methylprednisolone
- used alone or in combo for preventing & treating PONV, CINV, or radiation-induced nausea & vomiting
- Efficacy is thought to be due to release of 5-HT, reduced permeability of the blood–brain barrier, and decreased inflammation
cannabinoids for nausea & vomiting
- e.g. dronabinol, nabilone
- used for prevention & treatment of refractory or delayed CINV
benzodiazepines for nausea & vomiting
- e.g. lorazepam, alprazolam
- used to prevent & treat CINV
- used as an adjunct to antiemetic agents
serotonin antagonists for nausea & vomiting
- e.g. ondansetron, granisetron, dolasetron, tropisetron, palonosetron
- most useful for PONV
- also CIVN, radiation induced nausea
- most well tolerated, dose-related QT changes have been reported (so ECG monitoring recommended for at risk patients)
neurokinin-1 receptor antagonists for nausea & vomiting
- e.g. aprepitant, rolapitant, netupitant
- effective for preventing acute and delayed CINV, PINV
- numerous drug interactions! (as CYP inhibitor)
olanzapine for nausea & vomiting
- antipsychotic agent that has effects at D2, 5-HT2c, and 5-HT3 receptors
- combination therapy for prevention of CINV in patients receiving highly emetogenic chemotherapy
Sea-legs product
- sold for the prevention of travel sickness
- contains meclozine, an antihistamine which is generally less sedating than promethazine
- Meclozine is a Pharmacy Only Medicine and not for use in children under six years old.
- Taken the night before travel or one hour before travel and the dose can repeated every 24 hours if necessary.
- Can cause drowsiness thus making it dangerous to drive or operate machinery. Limit alcohol intake
Scopoderm TTS product
- sold for the prevention of motion sickness
- contains hyoscine (scopolamine) (an antichlonergic medicine)
- a topical patch, needs to be placed behind the ear at least five hours before travelling (though eight hours produces the best effect)
- wash hands after handling the patch, & to wash area after patch removal
- Drowsiness can occur with this medicine and patients must be warned about driving or operating machinery
sea band product
- sold for “the control of nausea & motion sickness without drugs”
- is homeopathic and may be of benefit to those who cannot take other medicines
- bands aim to apply constant pressure to the Nei-Kuan pressure points in the wrists which may help reduce the feelings of nausea
- Patients should be advised to place the bands in the middle of the inner wrist, about three finger widths from the crease where the wrist joins the hand.
Phenergan product
- 1st gen antihistamine
- PHARMACIST ONLY
- Phenergan is a **brand name of the generic promethazine **which is a sedating antihistamine
- pharmacists must be wary about the potential abuse of this type of medicine
- Patients should be warned about drowsiness and avoiding driving and operating machinery.
nausicalm product
- sold for the treatment of nausea and prevention of travel sickness
- contains cyclizine, an antihistamine which is generally less sedating than promethazine
- PHARMACIST ONLY (max 6 tablets)
- adult dose: 1 tablet (50mg) taken 1–2 hours before travel
- Warnings: Drowsiness - do not drive or use tools or machines. Do not drink alcohol.
what is the likely mechanism that causes motion sickness?
conflicting sensory input to brain due to differences between actual and expected patterns of movement or vision
heartburn
- Heartburn is a burning feeling that rises from the stomach or lower chest up towards the neck and is often a symptom of GORD.
- Heartburn does not refer to pain of cardiac origin although pharmacists should be alert for symptoms that might indicate heart disease.
what are some conditions you should try rule out when questioning a patient with dyspepsia?
(i.e. differential diagnoses for dyspepsia)
- gastric ulcer
- duodenal ulcer
- medicine-induced dyspepsia
- irritable-bowel syndrome (IBS)
- gastric or oesophageal cancer
- heart disease
- galstones
what are some questions you might ask a patient complaining of dyspepsia?
- AGE? The age of the patient is relevant as pathological conditions are more likely to occur in older patients (e.g. >50 years of age)
- DESCRIPTION OF THE PAIN? Both the location of the pain and it’s intensity may point towards a possible cause. Pain described as gnawing, sharp or stabbing may indicate more serious pathology. Intense or severe pain should be referred to exclude more serious conditions
- DOES PAIN RADIATE? Pain that radiates to other parts of the body may indicate more serious disease & should be referred e.g. cardiovascular pain may radiate to the left arm, shoulder or jaw
- ASSOCIATED SYMPTOMS? Symptoms such as persistent vomiting, altered bowel habit or black & tarry stools may indicate serious disease & should be referred
- WHAT MAKES IT WORSE (OR BETTER)? does eating make it better, or worse? Is it relieved by antacids? Certain types of food may aggravate symptoms for some people
- SOCIAL HISTORY? stress or rushed eating may worsen symptoms. Alcohol consumption often causes dyspepsia.
- HOW LONG has this been a problem?
what are some symptoms associated with heart burn?
- burping & regurgitation of food
- pain relieved by antacids
- burning sensation at front of chest after meals
what are 3 OTC products a patient can purchase for the treatment of GORD
- mylanta (antacid)
- gaviscon (anginate)
- losec (omeprazole) (proton pump inhibitor)