Mod 3 Lecture 3 FULL Lower GI DX Flashcards
Exam 2
What makes up the lower GI:
Small intestine
Large intestine (colon)
Nerve innervations
What is the role of small intestine?
Completes digestion
Pancreatic & intestinal secretions
Mucus protects gut wall
Absorbs nutrients and most water
Peptidase digests protein
Sucrases digest sugar
Site of enzymatic activity
Bile emulsifies fat
What is the role of the large intestine?
Reabsorbs some water and ions
Forms and stores feces
Bacteria break down remaining proteins
Facilitates passage of fecal contents out of the body.
What are the nerve innervations of the lower GI tract?
- Parasympathetic
- Sympathetic
lower GI tract: Parasympathetic
Increasing digestive activity
Lower GI tract: Sympathetic
Slowing digestive activity
Vasoconstriction in mucosa
Lower GI A&P:
What are the components of the small intestine?
Duodenum (upper), jejunum, ileum
What is the longest section of the GI tract? How long?
Longest section of GI tract ~ 20ft
How does peristalsis occur in small intestine?
Peristalsis via muscular rings
What occurs in the small intestine?
Enzymatic degradation & nutrient absorption
Where do the nutrients absorbed in the small intestine go?
Nutrients –> circulatory & lymphatic systems
Lower GI A&P: Small Intestine
Plicae circulars
circular folds within wall
Lower GI A&P: Small Intestine
What makes up the plicae circulars?
Villi & microvilli
Capillaries, nerves,lymphatic vessels
Lower GI A&P: Small Intestine
What does the villi and microvilli do in the small intestine?
↑ surface area for absorption
absorb nutrients through finger-like, tiny projections
Lower GI A&P: Small Intestine
What are protective features of the small intestine?
Pancreas ducts
Mucus production
Lower GI A&P: Small Intestine
What do the pancreatic ducts do in the small intestine?
pH neutralizing fluid
produce fluid with a pH of around 7
Lower GI A&P: Small Intestine
What does the pancreatic ducts do with digestive enzymes?
The pancreatic duct carries digestive enzymes from the pancreas to the small intestine
Lower GI A&P: Large Intestine
How large is it?
shorter ~ 5ft long
Lower GI A&P: Large Intestine
What happens to the chyme from the small intestine? How long is this process?
Chyme from small intestine –> large intestine ~ 3-5h
Lower GI A&P: Large Intestine
What does the small intestine have that the large intestine does not?
⍉ villi
Lower GI A&P: Large Intestine
What is the cecum
Cecum – beginning of large intestine, precedes colon
Lower GI A&P: Large Intestine
What is the order of the large intestine?
Ascending –> transverse –> descending –> sigmoid –> rectum –> anus
Lower GI A&P: Large Intestine
What occurs minimally in the colon?
Absorption of nutrients is minimal
Lower GI A&P: Large Intestine
How much fluid enters the colon each day?
1500 mL of fluid enters colon each day
Lower GI A&P: Large Intestine
What is reabsorbed in the colon?
Reabsorption of fluids, electrolytes, acids & bases
Lower GI A&P: Large Intestine
What is stored/formed in the colon?
Forms and stores feces
Lower GI A&P: Large Intestine
What is attached to the cecum of the large intestine?
Appendix, attached to cecum
Lower GI A&P: Large Intestine
What is the purpose of the appendix?
Aids in immunity
No function, but potential harm
Lower GI A&P: Large Intestine
What is the appendix a reservoir for?
Reservoir for good bacteria
Lower GI A&P: Large Intestine
What does the rectum do?
Fecal formation &storage
How does the defecation reflex compare in adults and infants?
Consciously controlled (⍉ infants)
How is the defecation reflex activated?
Feces –> stretch receptors –> spinal cord –> signal
How do the muscles move during defecation?
Relaxation of internal & external anal sphincters
Contraction of rectum
What muscles assist in defecation when needed?
Abdominal muscles~ assistance when needed
What innervations are involved in defecation control?
Innervations: sympathetic & parasympathetic
What is required for defecation control?
Requires intact muscular & nervous function
What does prolonging urges of defecation control lead to?
H2O reabsorption ~ difficulty to pass bowel movement (BM)
What is used to ID underlying cause and complications of GI tract?
Poop
What type of patient medical history do you collect about poop?
Usual BM pattern
HX of weight loss, anorexia, fatigue
PE
Cramping, fever, chills, N/V: Acute ~ infectious
Stool analysis & cultures
Frank Blood
bright, red surface of the stool, lesions in the rectum or anal canal and has not been “digested”
Stool analysis & cultures include:
Frank blood:
Occult blood:
Melena:
Steatorrhea:
(+) blood, pus, mucus ~ exudative diarrhea
Stool analysis & cultures
Occult Blood
small hidden trace amounts not visible but detected on fecal testing;
Stool analysis & cultures
How does occult blood result?
result of small bleeding ulcers in the stomach or small intestine
Stool analysis & cultures
Melena:
dark, tarry stool often resulting from significant bleeding higher in the digestive tract;
Stool analysis & cultures
Why does the dark color occur in melena:
dark color is due to hemoglobin being broken down by intestinal bacteria ~ upper GI bleed
Stool analysis & cultures
What does (+) blood, pus, mucus indicate?
exudative diarrhea
Stool analysis & cultures:
Steatorrhea:
“Fatty” stools
Frequent bulky, loose stools that are greasy, often with a foul odor
According to the Bristol Stool Chart, how many types of poop are there?
7 Types (study if you have time slide 8)
What is diarrhea?
Change in bowel pattern characterized by an increased frequency, amount, and water content of stool
What causes diarrhea to occur?
Results because of increased fluid secretion, decreased fluid absorption, or an alteration in GI peristalsis
How is diarrhea viewed in relation to disease?
Symptom of GI disease not a disease per se
What are the two groups of diarrhea?
Acute diarrhea
Chronic diarrhea
What is Acute Diarrhea?
> 3 stools within 24hrs that last < 14 days
What usually causes acute diarrhea?
Often caused by viral or bacterial infections or certain medications (e.g., antibiotics, antacids, and laxatives)
How does acute diarrhea progress?
Usually self-limiting, depending on the cause
Acute diarrhea is generally what? What are the symptoms?
Generally infectious and accompanied by cramping, fever, chills, nausea, and vomiting.
What may be present in acute diarrhea?
Blood (may be frank, occult, or melena), pus, or mucus may be present.
How are bowel sounds in acute diarrhea?
Bowel sounds may be hyperactive.
What kind of imbalances occur in acute diarrhea? What does this lead to?
Fluid, electrolyte, and pH imbalances (met acidosis).
What is chronic diarrhea?
Lasts longer than 4 weeks
What are the causes of acute diarrhea?
Causes: inflammatory bowel diseases, malabsorption syndromes, endocrine disorders, chemotherapy, and radiation
Approach to Management of Diarrhea
Strategies vary depending on etiology
Approach to Management of Diarrhea: Acute Diarrhea?
Acute diarrhea usually self-limiting
Approach to Management of Diarrhea:
Maintenance and correction of BOTH Acute Diarrhea and Chronic include?
Hydration, electrolyte, acid-base
Non-severe ~ PO
Severe or hyponatremia IV
Approach to Management of Diarrhea:
What does dietary fiber do?
Absorbs excess H2O & ↑ stool bulk
Beneficial for chronic diarrhea
Approach to Management of Diarrhea:
Why is skin care important?
Issue in bowel incontinence
Approach to Management of Diarrhea:
What is needed for infectious diarrhea?
ABX, when needed
What kind of infectious diarrhea would antibiotics be needed for ?
Severe traveler’s
C diff
What should be avoided when experiencing infectious diarrhea?
Avoid antidiarrheals
What is used to treat non- infectious diarrhea?
Antidiarrheal agents
Anticholinergics
Antispasmodics
What is C.diff?
Gram + bacillus anaerobe
What is Clostridium Difficile-Associated Diarrhea (CDAD):
Bacteria-related damage to the intestinal mucosa and colon
What are mild signs and symptoms of Clostridium Difficile-Associated Diarrhea (CDAD):
Mild: abdominal discomfort, nausea, fever, diarrhea, leukocytosis
What are severe signs and symptoms of Clostridium Difficile-Associated Diarrhea (CDAD):
Severe: toxic megacolon, pseudomembranous colitis, colon perforation, sepsis
What is antibiotic induced CDAD?
Broad spectrum antibiotics that disrupt normal flora
What are examples of antibiotics that lead to antibiotic induced CDAD?
Clindamycin, 2nd & 3rd gen cephalosporins, FQs
What are predisposing factors that lead to CDAD?
Surgery of the gastrointestinal (GI) tract
Diseases of the bowel (inflammatory bowel disease, colon cancer)
Weakened immune system (eg chemo)
Advanced age
Kidney disease
Use of proton pump inhibitors
Prior C. diff infection
What are the two most important ways in managing CDAD?
Discontinue offending ABX
Obtain stool cx to r/o C diff
What else (other than the two most important ways) should CDAD be managed?
ABX for CDI
What antibiotics are used for MILD CDAD?
Metronidazole PO 500mg TID 10-14 days, Vancomycin PO 4x/day 10-14d
What antibiotic should be given for severe/complicated CDAD?
Severe/complicated: Metronidazole 500mg IV q8 + Vancomycin PO 4x/day 10-14d
What other medication can be given for CDAD management?
Fidaxomicin
How should medication be administered in CDAD management?
Start empirically if lab confirmation delay
Antidiarrheal Classification:
What are the two broad groups of antidiarrheals?
Non-specific antidiarrheals (diphenoxylate, loperamide)
Specific antidiarrheals
What are examples of non-specific antidiarrheals? (opioids)
Non-specific antidiarrheals (diphenoxylate, loperamide)
How do Non-specific antidiarrheals (diphenoxylate, loperamide) act?
Act on or within the bowel to provide symptomatic relief only!
What does Non-specific antidiarrheals (diphenoxylate, loperamide) have to do with the cause of diarrhea?
⍉ influence underlying cause
What are the two agents in Non-specific antidiarrheals?
Opioid-derived agents
Non-opioid agents
What does Specific antidiarrheals treat?
TX underlying causes (e.g. IBD)
What are specific antidiarrheals used for?
(Give examples)
Anti-infectives for C Diff, traveler’s diarrhea
Agents to correct malabsorption diagnosis
Nonspecific Antidiarrhea Agents: Opioids
What is the 2 groups of nonspecific antidiarrheal opioids
Diphenoxylate [Lomotil] &
Loperamide (Imodium)
Nonspecific Antidiarrhea Agents: Opioids
What do Diphenoxylate [Lomotil] & Loperamide (Imodium) both activate in the GI tract?
Activate opioid receptors in GI tract
Nonspecific Antidiarrhea Agents: Opioids
What do Diphenoxylate [Lomotil] & Loperamide (Imodium) both do in the GI tract?
Decrease intestinal motility, slows intestinal transit to allow more time to absorb F&E
Nonspecific Antidiarrhea Agents: Opioids
When Diphenoxylate [Lomotil] & Loperamide (Imodium) activate opioid receptors, what happens?
Activation of opioid receptors decreases secretion of fluid into SI & increases absorption of fluid & salt
What is the goal of Nonspecific Antidiarrhea Agents: Opioids?
Goal: less H2O in LI –> less fluidity & volume of stools & decreased stool frequency
Nonspecific Antidiarrhea Agents: Opioids
What can high doses of opioid receptors lead to?
High doses can elicit typical morphine-like subjective responses
Nonspecific Antidiarrhea Agents: Opioids
How would you treat a severe OD of Nonspecific Antidiarrhea Agents: Opioids?
Severe OD: tx with naloxone
Nonspecific Antidiarrhea Agents: Opioids
How can you get Diphenoxylate [Lomotil]? In what form do they come?
Rx only
Tablets & liquid
Nonspecific Antidiarrhea Agents: Opioids
What is Diphenoxylate [Lomotil] formulated with? Why?
Formulated with atropine to discourage abuse (5ml = 2.5mg diphenoxylate + 0.025mg atropine)
Nonspecific Antidiarrhea Agents: Opioids
What does atropine do in Diphenoxylate to discourage abuse?
Atropine to discourage abuse (unpleasant side effects from high dose of atropine)
Nonspecific Antidiarrhea Agents: Opioids
What is Diphenoxylate [Lomotil] only used for?
Opioid used only for diarrhea
Nonspecific Antidiarrhea Agents: Opioids
How can you get Loperamide (Imodium)? In what form do they come?
OTC, 2mg capsules
Nonspecific Antidiarrhea Agents: Opioids
What is Loperamide (Imodium) similar to?
Structural analog of meperidine
Nonspecific Antidiarrhea Agents: Opioids
What does Loperamide (Imodium) do?
Suppresses bowel motility & fluid secretion into intestinal lumen
Nonspecific Antidiarrhea Agents: Opioids
What is Loperamide (Imodium) used for?
Used to treat diarrhea and to reduce the volume of discharge
Nonspecific Antidiarrhea Agents: Opioids
How is absorption of Loperamide (Imodium)?
Poor absorption, does not readily cross BBB
Nonspecific Antidiarrhea Agents: Opioids
What is the potential of abuse of Loperamide (Imodium)?
What is the half life?
Little or no potential for abuse
Half-life: 9-14 hrs
Nonspecific Antidiarrhea Agents: Non-Opioids
What are the types of Other Nonspecific AD: Non-Opioids?
- Bismuth Subsalicylate (Pepto-Bismol)
- Bulk-Forming Agents
- Anticholinergic Antispasmodics
Nonspecific Antidiarrhea Agents: Non-Opioids
What is the mode of action of Bismuth Subsalicylate (Pepto-Bismol)?
Coats wall of GI tract, adsorbing bacteria or toxins causing the diarrhea
Reduces prostaglandins
What do prostaglandins?
PGs induce inflammation & hypermotility
Nonspecific Antidiarrhea Agents: Non-Opioids
What is Bismuth Subsalicylate (Pepto-Bismol) used for?
Use in mild cases for prophylaxis & treatment of diarrhea & h pylori
Nonspecific Antidiarrhea Agents: Non-Opioids
What is the prophylaxis treatment dosages for Bismuth Subsalicylate (Pepto-Bismol)?
Px: 262mg tabs 4x/day x 3wks
Nonspecific Antidiarrhea Agents: Non-Opioids
What is the treatment dosages for Bismuth Subsalicylate (Pepto-Bismol)?
Tx: 2 tabs every 30 min x 8 doses
Nonspecific Antidiarrhea Agents: Non-Opioids
How is Bismuth Subsalicylate (Pepto-Bismol) administered?
Shake suspension well
Chewable tabs may be dissolved in mouth or chewed & swallowed
Nonspecific Antidiarrhea Agents: Non-Opioids:
What is a bulk forming agent?
Methylcellulose and Psyllium
Nonspecific Antidiarrhea Agents: Non-Opioids:
What does Methylcellulose do?
Paradoxical laxatives, refer to constipation
Makes stools more firms less watery
Nonspecific Antidiarrhea Agents: Non-Opioids:
What are examples of anticholinergic antispasmodics?
Atropine,
dicyclomine (bentyl)
Nonspecific Antidiarrhea Agents: Non-Opioids:
What is the mode of action of anticholinergic antispasmodics?
Muscarinic antagonists
Block vagal tone –> prolong gut transit time
Nonspecific Antidiarrhea Agents: Non-Opioids:
What should Anticholinergic Antispasmodics be used for?
Relief of cramping
Nonspecific Antidiarrhea Agents: Non-Opioids:
What should Anticholinergic Antispasmodics NOT be used for?
⍉ effect on fecal consistency/volume
Nonspecific Antidiarrhea Agents: Non-Opioids:
What are the adverse effects of Anticholinergic Antispasmodics?
Blurred vision, photophobia, dry mouth, urinary retention, tachycardia
Patho of Constipation:
What is constipation characterized by?
Change in bowel pattern characterized by infrequent passage of stool in reference to the individual’s typical bowel pattern.
Patho of Constipation:
How are stools and process of creating stool in constipation?
Hard & dry stools, excessive straining, prolonged effort, incomplete evacuation
Patho of Constipation:
How are stools IN the body during constipation? What does this lead to?
Stool remains in the large intestine longer than usual, increasing the amount of water reabsorbed by colon.
Patho of Constipation
What is constipation determined by?
Determined by stool consistency > number of BMs
Patho of Constipation
What are causes of constipation?
Causes: low-fiber diet,
inadequate physical activity,
insufficient fluid intake,
delaying the urge to defecate,
laxative abuse,
stress (SNS stimulation slows GI motility), travel,
bowel diseases,
certain meds (eg narcs, anticholinergics, fe supplements),
depression,
neurologic diseases (eg CVA, Parkinson’s, SCI) and
colon cancer.
Patho of Constipation
What are the benefits of fiber in constipation?
Absorbs water: Softens feces and increases size
Can be digested by colonic bacteria –> growth increases fecal mass
Clinical Presentation & Complications
What are symptoms of constipation?
Straining with defecation
Hard stools
Sensation of incomplete emptying
Manual maneuvers to facilitate stool evacuation
Fewer than three bowel movements per week
Infrequent stools
Prolonged effort
Unsuccessful defecation
Clinical Presentation & Complications
What are complications of stool?
anal bleeding, anal fissure, bowel incontinence (leakage of liquid stools), hemorrhoids, obstipation, intestinal obstruction, bowel perforation
Obstipation
a severe form of constipation that results in a person being unable to have a bowel movement.
How is constipation diagnosed?
H&P, Bristol Stool chart, digital exam, abd XR, UGI series, barium swallow, colonoscopy
What is the treatment of constipation?
Increasing dietary fiber with concomitant increase in hydration
Proper bowel functioning is dependent on whaat?
Proper bowel function is highly dependent on dietary fiber (bran is best source)
What is the best source of dietary fiber?
(bran is best source)
When fiber is given for constipation, what does it do?
Fiber absorbs water –> soft feces, increased mass
What do colonic bacteria do when fiber and hydration are given as treatment for constipation?
Digested by colonic bacteria –> increased fecal mass
What is something (other than bran) that is rich in fiber?
Flax seed
What are treatments for constipation (other than increasing fiber and hydration)?
increasing physical activity
defecating when initial urge is sensed
stool softeners & fiber supplements
limited use of laxatives and enemas
Laxatives have how many modes of actions?
What is the general goal of laxative?
Various MOA ~ stimulate defecation
What do stimulants do to stool? What does this do? Who is it good for?
Soften stool –prevents straining, esp good in cardiac pts to prevent elevation of BP & vasovagal
Increase fecal mass & volume
What do laxatives compensate for?
Compensates for loss of abdominal tone & perineal muscles in elderly
What do laxatives do to fecal transit?
Speed up fecal transit
How can laxatives be used for procedures?
Facilitate rectal evacuation – empty bowel before procedure
How does laxatives help with bedridden patients?
Prevent fecal impaction in bedridden patients
How do laxatives effect elimination?
Reduce painful elimination
What are contraindications and precautions for laxatives?
Acute surgical abdomen
Habitual use/abuse
Abd pain, cramps, appendicitis, inflamm bowel disease
Fecal impaction – increased peristalsis could cause bowel perforation
Caution in pregnancy – GI stimulate might induce labor
Not for habitual use
What are the classifications of laxatives?
Bulk-forming
Surfactant
Stimulant
Osmotic.
There is a graph on slide 25 to look at?
What is an example of a bulk forming laxative?
Psyllium [Metamucil]
Bulk forming laxative: Psyllium [Metamucil]
What does it do to food? Water? Waste?
Soften and increase bulk of digested food, so waste can more easily pass
Absorb water
Fecal swelling–> peristalsis
What is an example of a surfactant laxative?
Docusate sodium [Colace]
Surfactant laxatives: Docusate sodium [Colace]
What does it do?
Increase water in the stool, which helps soften it and makes it more comfortable to pass
What is an example of stimulant laxatives?
Bisacodyl [Dulcolax]
Stimulant laxatives: Bisacodyl [Dulcolax]
What does it do?
Stimulate intestinal walls, which causes the muscles’ contraction to clear the bowel
Soften feces by increasing water secretion & electrolytes into intestine
What is an example of Osmotic laxatives?
Milk of magnesia (MOM),
Polyethylene glycol (PEG),
lactulose
Osmotic laxatives: Milk of magnesia (MOM), Polyethylene glycol (PEG), lactulose
What do they do?
Draw water into the intestine
Osmotic action retains water soften feces, fecal swelling peristalsis
What does the osmotic action of osmotic laxatives allow them to do?
Osmotic action retains water –> soften feces, fecal swelling –> peristalsis
What are examples bulk forming laxatives?
Psyllium, Methylcellulose
What do bulk forming laxatives work similar to?
Function similarly to dietary fiber
How are bulk forming laxative absorbed and digested?
Nondigestible & nonabsorbable
How do bulk forming laxatives work?
Swell with water to form a gel that softens and increases fecal mass
What is the process of how bulk forming laxatives work?
Fecal mass swelling –> stretches intestinal wall –> speeds up transit time –> peristalsis
Where do bulk forming laxatives work?
Works in SI/LI
What do bulk forming laxatives do to food?
Soften and increase bulk of digested food, so waste can more easily travel through and leave the body
What kind of people are bulk forming laxatives good for?
Good for patients with ileostomy/colostomy
What are bulk forming laxatives preferred for?
Preferred temporary treatment of constipation
What do bulk forming laxatives do for diarrhea?
Can provide symptomatic relief of diarrhea
What do bulk forming laxatives do for ileostomy and colostomy?
Reduce discomfort/inconvenience with ileostomy/colostomy
How long does it take for bulk forming laxatives to form soft stool?
Produce soft stool 1-3 days
What is the dose for bulk forming laxatives?
1 heaping tsp/package in 8oz H2O 1-3x/day
What are the adverse effects of bulk forming laxatives?
Adverse effects are minimal
Esophageal obstruction
What should be done to avoid esophageal obstructions that can occur with bulk laxatives?
Give with plenty H2O or juice to prevent esophageal obstruction
How is the esophageal obstruction that occurs with bulk forming laxatives?
Obstructionorimpaction forms a sticky substance when combined with water
What should you do if esophageal obstruction is suspected with bulk forming laxative use?
Avoid if suspected
Avoid if there’s narrowing of intestinal lumen or impeded passage to prevent obstruction
How are surfactant laxatives (like Docusate sodium (Colace)) taken?
PO: tablets, capsules, liquid, syrup
OTC
What is the mode of action of surfactant laxatives (like Docusate sodium (Colace))?
MOA “stool softener”
When does “stool softening” occur with surfactant laxative use?
Produce a soft stool several days after onset of treatment
What does surfactant laxatives promote?
What does this lead to?
Promotes incorporation of water into stool –> softer fecal mass
Why is it important that surfactant laxatives make stool softer?
Makes stool more comfortable to pass
Where does surfactant laxatives work?
Works in small intestine & colon
How is surfactant laxatives used?
(amount)
Soft, formed stool ~ 1-3d, can take 3-5 days
What is surfactant laxatives used for?
PX opioid-induced constipation, postop, pregnancy
What is the dose of surfactant laxatives?
Dose
Adults 50-500 mg/day
Usually given 3x/day
What is the example of Stimulant Laxatives?
Bisacodyl (Ducolax, Senna/Senekot)
What is the mode of action of Stimulant Laxatives like Bisacodyl (Ducolax, Senna/Senekot)?
What does it stimulate?
Stimulate intestinal motility causes the muscles’ contraction to clear the bowel
What is the mode of action of Stimulant Laxatives like Bisacodyl (Ducolax, Senna/Senekot)?
What does it do to water?
Increase amounts of water and lytes in intestinal lumen
Where does Stimulant Laxatives (Bisacodyl (Ducolax, Senna/Senekot)) work?
Works in the colon
What is Stimulant Laxatives Bisacodyl (Ducolax, Senna/Senekot) used for?
TX of constipation from slow intestinal transit & opioid-induced
How is Stimulant Laxatives Bisacodyl (Ducolax, Senna/Senekot) used? (abusable?)
Widely used & abused
What kind of stool does stimulant laxative bicacodyl create when given PO?
Produce semifluid stool with 6-12h
When is stimulant laxative bisacodyl given? (What time of day)
Given QHS to produce BM next day
How should stimulant laxative bicacodyl be given? How is the PO med taken?
EC to prevent gastric irritation
Swallow whole, no chewing, crushing
How do stimulant laxatives like bisacodyl act when they are in PR SUPP form?
Act rapidly – 15-60 min
What is the adverse reaction of stimulant laxative like Bisacodyl when they are given PR SUPP?
What should you avoid with this drug? Why?
ADE burning
Avoid long-term - proctitis
Proctitis
Proctitis is inflammation of the lining of the rectum.
Senna is derived from what?
What does it do to urine?
Plant-derived, stimulant actions (stimulates the bowels to move)
Yellow-brown/pink urine discoloration
What are ingredients in osmotic laxatives?
Sodium phosphate, Mg OH
What do osmotic laxatives do with fecal mass, what does this lead to?
softens and swells fecal mass, which stretches the intestinal wall to stimulate peristalsis
What does a low dose of osmotic laxatives do? What does a high dose of osmotic laxatives do?
Low dose – watery stool 6-12 hrs,
high dose 2-6 hrs (eg bowel cleanse prep)
Osmotic Laxatives:
Polyethylene Glycol-PEG (Miralax)
How is it administered?
How long may it take a BM to occur?
17gm (low dose) once a day dissolved in 4-8 oz of liquid
BM may not occur for 2-4 days
Osmotic Laxatives:
Where do they work?
Works in small intestine & colon
Osmotic Laxatives:
What are adverse effects?
Dehydration, nausea, bloating, cramping, flatulence
Acute renal failure
Osmotic Laxatives:
What are adverse effects that can occur because of renal failure?
Mg can accumulate to toxic levels
Sodium retention
Osmotic Laxatives:
What occurs with sodium retention in renal failure from osmotic laxative use?
Sodium retention: Exacerbated heart failure, hypertension, edema, can cause RF in kidney disease
ADEs of Osmotic Laxatives:
What drug interactions can occur?
Interactions with Ace-Is, ARBs, diuretics (drugs that alter renal, fxn)
ADEs of Osmotic Laxatives:
Interactions with Ace-Is, ARBs, diuretics (drugs that alter renal, fxn)
What can these lead to?
Dehydration & precipitation of CaP in renal tubules
Glycerin suppository:
What kind of agent is it?
Osmotic agent
Glycerin suppository:
What does it do to stool? What may it stimulate?
Lubricates & softens hardened, impacted stool
May also stimulate rectal contraction
Glycerin suppository:
How long does it take for effects to occur?
Evacuation occurs in about 30 min post-insertion
Glycerin suppository
What are glycerin suppository useful for?
Useful for re-establishing normal bowel function following termination of chronic laxative use
Bowel-Cleansing Products for Colonoscopy (Osmotic Lax):
What are they used for?
Allow for good visualization of the bowel
Bowel-Cleansing Products for Colonoscopy (Osmotic Lax):
What are the types?
Sodium phosphate (OsmoPrep)
Polyethylene glycol (PEG) plus electrolytes (ELS) (Go-lytely)
Sodium phosphate (OsmoPrep)
What is the dosages?
Dosage: 20 tabs evening, 20 tables AM with clear liquid
Sodium phosphate (OsmoPrep)
What are the most common adverse effects?
Most common adverse effects are nausea, bloating, and abdominal discomfort.
Sodium phosphate (OsmoPrep)
What can occur because of kidney disease and advanced age?
Can cause dehydration and electrolyte disturbance in kidney disease, advanced age
Bowel-Cleansing Products for Colonoscopy (Osmotic Lax):
What MUST patients do when consuming Sodium phosphate (OsmoPrep)?
Pts must drink large volume clear fluid before, during, after dosing
Bowel-Cleansing Products for Colonoscopy (Osmotic Lax):
What is a rare adverse effect of Sodium phosphate (OsmoPrep)?
Hyperphosphatemia rare - can cause renal damage if pre-existing conditions (eg kidney disease adv age)
Bowel-Cleansing Products for Colonoscopy (Osmotic Lax):
What does not occur with Polyethylene glycol (PEG) plus electrolytes (ELS) (Go-lytely)? Why?
Isoosmotic with body fluids, so dehydration & electrolyte balance does not occur
Bowel-Cleansing Products for Colonoscopy (Osmotic Lax):
Polyethylene glycol (PEG) plus electrolytes (ELS) (Go-lytely): Isoosmotic with body fluids, so dehydration & electrolyte balance does not occur
Who is Polyethylene glycol (PEG) plus electrolytes (ELS) (Go-lytely) safe for?
Safe for pts with lyte imbalances, HF, kidney, liver disease
Bowel-Cleansing Products for Colonoscopy (Osmotic Lax):
What is Polyethylene glycol (PEG) plus electrolytes (ELS) (Go-lytely) require?
Requires ingestion of large volume of bad-tasting liquid
Bowel-Cleansing Products for Colonoscopy (Osmotic Lax):
How is the volume of Polyethylene glycol (PEG) plus electrolytes (ELS) (Go-lytely)?
Volume administered is huge, typically 4 L. Patients must ingest 250 to 300 mL every 10 min x 2 to 3hrs
Newer products: GaviLyte-H + bisacodyl + PEG-ELS – the volume is cut in half
Bowel-Cleansing Products for Colonoscopy (Osmotic Lax):
What are the most common adverse effects of Polyethylene glycol (PEG) plus electrolytes (ELS) (Go-lytely)?
Most common adverse effects are nausea, bloating, and abdominal discomfort.
Laxative Abuse: What is a misconception?
Misconception that bowel movements must occur daily
Laxative Abuse: What is often mistaken for constipation?
Bowel replenishment after evacuation can take 2 to 5 days; often mistaken for constipation
Laxative Abuse:
Consequences?
Diminished defecatory reflexes, leading to further reliance on laxatives
Electrolyte imbalance, dehydration, colitis
Pathogenesis of Inflammatory Bowel Disease:
What is it?
Exaggerated immune response directed against normal bowel flora
Pathogenesis of Inflammatory Bowel Disease:
What are initiating triggers that are genetic?
Antimicrobial peptides
Autophagy
Handling of bacteria
Chemokines
Cytokines
Pathogenesis of Inflammatory Bowel Disease:
What are initiating triggers that are environmental?
Microorganisms
Diet
Infections
Stress
NSAIDs
Appendectomy
Smoking
Antibiotics
Pathogenesis of Inflammatory Bowel Disease:
What are the four phases?
Phase I: Pre-disease stage
Phase II: Acute intestinal inflammation
Phase III: Chronicity or resolution
Phase IV: Tissue Destruction and complications
Overview of Inflammatory Bowel Disease:
What are two major diseases?
Crohn’s Disease
Ulcerative colitis
Overview of Inflammatory Bowel Disease:
Crohn’s Disease
What is it? When does it start?
Autoimmune disease
Starts in adolescence through early adulthood
Overview of Inflammatory Bowel Disease:
Crohn’s Disease
What is common?
Abscesses, fissures, fistula & obstruction common
Mass of inflammatory tissue (granuloma) surrounded by ulceration
Overview of Inflammatory Bowel Disease
Crohn’s Disease:
What kind of inflammation occurs?
Mass of inflammatory tissue (granuloma) surrounded by ulceration
Transmural Inflammation:
Overview of Inflammatory Bowel Disease
Crohn’s Disease:
What is Transmural Inflammation?
Transmural Inflammation: involves deeper layers of bowel wall
Overview of Inflammatory Bowel Disease:
Crohn’s Disease:
What areas are affected? What area is most affected?
Any area of digestive tract may be affected, mouth —> anus
Terminal ileum mostly affected
Overview of Inflammatory Bowel Disease:
Crohn’s Disease:
How does it affect areas of the body?
Affects all layers of the gastrointestinal tract in a “skip” pattern
Cobblestone lesions
Overview of Inflammatory Bowel Disease:
Ulcerative colitis: What age does it occur?
Any age occurs
Overview of Inflammatory Bowel Disease:
Ulcerative colitis: Where does it begin and extend?
Begins in rectum, may extend throughout colon
Overview of Inflammatory Bowel Disease:
Ulcerative colitis: how is the mucosa?
Mucosa inflamed continuously confined to the mucosa
Friable mucosa
Crypt abscess formation, necrosis, ragged ulceration of mucosa
Overview of Inflammatory Bowel Disease:
Ulcerative colitis:
What kind of lesions occur?
Small erosions –> superficial ulcers
Overview of Inflammatory Bowel Disease:
What happens to the colon?
Edema & thickening of muscularis mucosa may narrow lumen of colon
Overview of Inflammatory Bowel Disease:
Ulcerative colitis: What does crypt abscess formation, necrosis, ragged ulceration of mucosa lead to?
Accumulation of inflammatory & WBCs within the crypts of GIT
–> Tube-like glands in lining of GIT
slide 40 read it
Clinical manifestations of Crohn’s disease?
Inflammation
Melena if lesions erode blood vessels
Malabsorption
Anemia & fatigue
Deep fissuring ulcers in intestines
Clinical manifestations of Crohn’s disease:
What symptoms does inflammation in Crohn’s disease lead to?
Diarrhea/cramping/abd pain
Loose stool/semi-formed
Clinical manifestations of Crohn’s disease:
What does malabsorption in Crohn’s lead to?
Anorexia; nausea; vomiting; weight loss–> malnutrition
Clinical manifestations of Crohn’s disease:
What causes Anemia and fatigue in Crohn’s?
Lack of VitB12 absorbed in terminal ileum
Clinical manifestations of Crohn’s disease:
What can occur because of constipation in Crohn’s?
Anal fissures from constipation, strictures, fistulas, and abscesses from transmural inflammation and micro perforation of diseased bowel
Clinical manifestations:
What occurs in Ulcerative colitis due to inflammation?
Bloody, mucus diarrhea due to inflammation & damage to mucosa epithelium
- Up to 10-20x/day
Clinical manifestations:
What occurs in Ulcerative colitis in addition to a need to defecate?
Spasms of the rectum along with a need to defecate
Clinical manifestations:
What occurs in Ulcerative colitis from rectal bleeds?
Severe Iron Deficiency Anemia from rectal bleed
Clinical manifestations:
What occurs in Ulcerative colitis from fludi loss?
Dehydration from fluid loss
Drugs for IBD: What do drugs do in general?
Not curative; may control disease process
Drugs for IBD: What are they?
5-Aminosalicylates - 5-ASAs (sulfasalazine; mesalamine)
Glucocorticoids
Immunosuppressants
Immunomodulators (infliximab – Remicade)
Antibiotics (metronidazole & ciprofloxacin) for Crohn’s
Drugs for IBD: What are examples of 5-Aminosalicylates - 5-ASAs
(sulfasalazine; mesalamine)
Drugs for IBD: What does 5-Aminosalicylates - 5-ASAs (sulfasalazine; mesalamine) do?
Reduces inflammation; suppresses prostaglandin synthesis and migration of inflammatory cells into affected region
Drugs for IBD: What are immunosuppressants Azathioprine [Imuran], mercaptopurine [Purinethol], cyclosporine, methotrexate used for?
Used to maintain remission in both CD & UC
Used when pts not responding to traditional therapy
Drugs for IBD: What are examples of Immunosuppressants?
Azathioprine [Imuran], mercaptopurine [Purinethol], cyclosporine, methotrexate
Drugs for IBD: What are immunosuppressants Azathioprine [Imuran], mercaptopurine [Purinethol], cyclosporine, methotrexate:
What are adverse reactions
ADR: bone marrow suppression
Drugs for IBD: What are examples of Immunomodulators
Immunomodulators (infliximab – Remicade)
Drugs for IBD: What do Immunomodulators (infliximab – Remicade) what is most common reactions?
What is most concerning?
Infections & infusion reactions most common (chills, itching, cardiopulm sx, BP flucuations)
Tb & opportunistic infections, lymphoma most concerning
Drugs for IBD: What do Immunomodulators (infliximab – Remicade) do?
Monoclonal antibody designed to neutralize tumor necrosis factor (TNF), a key immunoinflammatory modulator
Drugs for IBD:
What are examples of antibiotics for Crohn’s?
What are they for?
(metronidazole & ciprofloxacin)
Treatment for abscesses