GI: Disorders of Upper/Lower Systems Flashcards
Emesis Defense Mechanism
rid of toxic substances
“vomiting center”
in medulla
Emetics
induce vomiting emergency only (poisons/overdose) > risk for aspiration/exacerbation of tissues if caustic substance
Intractable n/v =
suspect bowel obstruction
Afferent/vagal splanchnic fibers
stimulate vomiting
distension irritation infection obstruction dysmotility
receptor: vagal, 5-HT
Vestibular System
stimulate vomiting
motion infection
receptors: histamine, muscarinic, cholinergic
Higher CNS Centers
stimulate vomiting
ICP infection tumor hemorrhage sights smells emotions
Receptors: various
Chemoreceptor Trigger Zone
located outside BBB (near medulla)
stimulate vomiting
opioids chemo toxins hypoxia uremia acidosis radiation therapy
Receptors: 5-HT and Dopamine
CAM Antiemetics
peppermint
ginger
Serotonin Receptor Antagonist (AntiEmetics)
ondansetron (-trons)
block 5HT receptors
TX: prophylaxis of chemo/radiation induced N/V and post op N/V
SE: constipation diarrhea headache hypoxia [severe: prolonged QT torsades serotonin syndrome]
interx: SSRIs/SNRIs/MAOIs/mirtazpine/fentanyl/lithium/tramadol (serotonin syndrome)
C
Anticholinergic/Antihistamines (AntiEmetics)
scopolamine, meclizine
tx: post op N/V, motion sickness
SE: xerostomia dizziness somnolence blurred vision mydriasis (dilation) [serious: glaucoma psychotic disorder eclampsia]
contra: acute angle glaucoma
interx: other anticholinergics/cns depressants
C
Phenothiazines
Antiemetic/Anti Dopaminergic/Anti Psychotic
prochlorperazine promethazine
blocks dopamine receptors in brain/inhibits signals to vomiting center in medulla
TX: severe n/v, given rectally but also po/im
SE: anticholinergic symptoms dry mouth sedation constipation orthostatic hypotension tachycardia extrapyramidal symptoms
BBW: elderly w/ dementia = death
contra: comatose pts, children <2/<20lbs, narrow-angle glaucoma, BMS, severe hepatic/cardiac impairment
interx: CNS depressants
TCAs = hypotensive effects/anticholinergic effects
C
Benzamides (Antiemetic/Antidopaminergic)
metoclopramide trimethobenzamide HCL
promotes motility in upper GI tract/increases gastric emptying
TX: chemo/GERD/gastroparesis/post-op N/V
SE: fluid retention headache somnolence fatigue [serious: nms tardive dyskinesia]
BBW: irreversible tardive dyskinesia
contra: epilepsy, GI hemorrhage, obstruction/perforation, pheochromocytoma (htn crisis)
interx: antipsychotics, snris, ssris, tcas (nms) - decreased digoxin levels, insulin (hyperglycemia)
C
Esophageal Disorders common manifestations
pain
alteration in ingestion
bleeding
Acquired esophageal disorders
rings/webs
diverticula
tumors
hiatal hernia
congenital esophageal disorders
webs
esophageal atresia
traumatic esophageal disorders
perforation
mallory-weiss tear
foreign bodies
food impaction
motiilty esophageal disorders
dysphagia
achalasia
diffuse esophageal spasms
mucosal integrity esophageal disorders
GERD
barret esophagus
esophagitis
System disease r/tesophageal
scleroderma esophagus
dermatologic disease
Esophageal rings
circular ring either membrane or muscular around esophageal lumen (not always narrowing)
B Ring
most common
found at gastroesophageal junction (membraneous)
Schatzi Ring
cases dysphagia
symptomatic B ring
A Ring
less common
occurs higher in lower esophagus
muscular in nature
Esophageal Rings s/s
can be asymptomatic
dysphagia dependent on degree of obstruction
dysphagia often chronic/episodic
symptoms of heartburn/regurgitation
esophageal rings tx
dietary restrictions
first ling: endoscopic dilation therapy
incisional is eh
Esophageal Webs
tin, membranous tissue in esophageal lumen
decreases diameter of esophageal lumen
can be congenital or acquired
esophageal webs s/s
can be asymptomatic typical presentation: dysphagia w/ solids acute food impaction nasopharyngeal reflux/aspiration spontaneous perforation
esophageal webs tx
dietary restrictions
first ling: endoscopic dilation therapy
esophagitis
irritation and inflammation of esophageal tissues leads to esophageal damage
types of esophagitis
eosinophilic (many causes)
radiation (tx of thoracic cancers)
corrosive
pill (lodged pill)
Esophageal diverticula
pressure increase in esophageal lumen > mucosa protrudes thru weakened wall > produces outpouching
esophageal diverticula eitology
acquired
most common in impaired motility of esophagus
can be r/t inflammatory disease of mediastinum
esophageal diverticula s/s
mostly asymptomatic can have dysphagia/heartburn gurgling audible during swallowing with stethoscope maybe neck mass if large need a scope to confirm
esophageal diverticula tx
depends
surgical for large (but risk for irritation/inflammation)
esophageal perforation
tear/rupture and hole through esophageal layers
esophageal perforation causes
endoscopy/ng tube insertion/intraoperative injury foreign body caustic substance blunt/penetrating trauma malignancy/infection forceful vomiting
esophageal perforation s/s
pain pneumomediastinum crepitus system infection/sepsis hematemesis (mallory-weiss tear)
esophageal perforation tx
varies always npo decompressive therapies esophageal stent surgery
hiatal hernia
herniation of stomach through esophageal hiatus of diaphragm
lower esophageal sphincter permits reflux of gastric contents
sliding or paraesophageal
multifactoral
Hiatal Hernia s/s
can by asymptotic
involves symptoms of gerd
type 4 (dyspnea, exercise intolerance, syncope, audible bowel sounds @ lung base)
hiatal hernia tx
medications for symptomatic gastric reflux
maybe surgery
Gastroesophageal Reflux Disease
failure of LES and diaphragm to prevent reentry of gastric contents
reflux of acid/pepsin/bile in esophagus
development of esophageal erosions/ulcerations
multifactorial
GERD risk factors
decreased LES tone pregnancy obesity impaired gastric motility surgical vagotomy decreased edogenous gastrin levels
GERD s/s
heartburn epigastric pain regurgitation after meals
extra-esophageal symptoms: acid injury to tooth enamel, throat pain, hoarseness, dysphonia, excessive throat clearing, chronic cough, globus, dysphagia
serious comp: esophageal cancer
GERD TX
medication (PPI h2 receptor blockers antacids)
diet
behavioral/lifestyle changes
surgery
Barret Esophagus
chronic exposure to gastric secretions (GERD)
esophageal stem cell metaplasia into columnar cells (rougher and pink)
can devlop carcinoma
Barrett Esophagus s/s
heartburn
regurgitation
Barret Esophagus tx
aggressive treatment of GERD (reversible)
biopsies
Esophageal Cancer
division of abnormal cells in esophagus = malignant growth/tumor
RF: smoking, GERD, obesity
esophageal cancer s/s
progressive dysphagia for solids weight loss heartburn hoarseness dry cough pneumonia odynophagia
esophageal cancer tx
chemo/radiation/surgery
palliative stenting
prevention: fruits/veggies in diet
associated cardinal GI symptoms
pain
altered ingestion
altered digestion
gi bleeding
stomach disorders of secretion
peptic ulcer disease ulcers gastrinoma gastritis stomach cancer
stomach disorders of motility
gastroparesis
gastric outlet obstruction
pyloric stenosis
peptic ulcer disease
increased gastric acid secretion (pepsin & HCl) > weakened mucosa > erosion/ulceration
peptic ulcer disease causes
most common: h. pylori infection/NSAIDS
Risk factors: smoking, caffeine, excessive alcohol/drug use, stress
PUD s/s
may be asymptomatic
epigastric pain/dyspepsia > bleeding/obstruction > perforation/peritonitis (x-ray will show free air under diaphragm)
PUD tx
id causative factor
h. pylori (3 or 4 ABX)
NSAIDS (h2 receptor antag and stop NSAID)
promote ulcer healing, prevent recurrence (healing takes 4-8 weeks)
PUD additional medications
combo abx
sucralfate (coats ulcer/pretoects it - avoid antacids w/in 30 min r/t constipation -B)
misoprostol (prostaglandin E analogue, inhibits acid/stimulates production of mucus - X)
metoclopramide (makes upper intestines contract - contra for tardive dyskinesia/obstruction/perforation/hemorrhage/pheochromocytoma)
Peritonitis
inflammation of ab cavity/lining due to infection or organ perforation
Peritonitis causes
perforations in stomach/intestine/gallbladder/appendix
PID (pelvic inflammatory disease) in women due to STI
can develop after surgery
Peritonitis s/s
ab tenderness pain vomiting fever decreased GI tract activity bowel obstruction increased WBC free air/gas in cavity indicates a rupture
peritontis tx
abx or surgery if needed
Proton Pump Inhibitors
Antiulcer
omeprazole (-prazoles)
reduce acid secretion by binding irreversibly to ions
tx: short term for PUD GERD and erosive esophagitis
takes a little bit to reach therapeutic levels
SE: HA, n, diarrhea, rash ab pain (longterm: increased risk of cancer, atrophic gastritis and hypomagnesemia)
admin: before breakfast on empty stomach
contra: under 18 yrs old
interx: diazepam, phenytoin, CNS depressant (increase levels), warfarin/alcohol/ginko&st. john’s wort
C
H2 Receptor Antagonists
Antiulcer
rantidine (tidine)
block H2 receptors in stomach to decrease acid production
TX: PUD
SE: HA (cimetidine crosses BBB = confusion/CNS depression) possible decrease in RBC/WBC/platlets impotence
admin: after meals/monitor liver/renal fx
contra: acute porphyria rantidine only give to children
interx: -conazoles)
B
Antacids
antiheartburn
calcium carbonate, sodium bicarbonate, aluminum hydroxide, magnesium hydroxide, combs
neutralizes stomach acid by increasing pH of stomach
does not reduce volume of acid secretion
TX: relief of heartburn r/t PUD/GERD
SE: constipation (^ aluminum doses = hypophosphatemia)
admin: 2 hours before/after other drugs
contra: bowel obstruction
interx: aluminum inhibits absorption of iron
C
Gastritis Acute
imbalance between mucosal injury/repair
mucosal hyperemia/erosive changes
transient mucosal inflammation
mucosal atrophy > loss of glands/parietal cells >chronic lymphoplasmacytic inflammation >intestinal metaplasia
Gastritis Chronic
begins w/ superficial gastritis
progresses to atrophic gastritis then gastric atrophy
gastric glandular structures are lost/converted to intestinal phenotypes (metaplasia)
gastric atrophy (precursor to cancer)
h. pylori organisms > mucous layer of surface epithelium > foci of acute/chronic inflammation > intestinal metaplasia
Acute gastritis causes
infection induce (h. pylori) drug-induced (nsaids, steroids, chemotherapy, alchol, iron) ulcerhemorrhagic (due to critical illness/stress, ischemic changes by shock/hypotension/vasoactive substances) hematemesis, melena
Chronic gastritis causes
type a: autoimmune (crohn’s disease, wegener granulomatosis, sarcoidosis) slow onset and ^ risk of adenocarcinoma
type be: infection induced (h. pylori) carbon urea breath tests
comp: duodenal/gastric ulcers/carcinoma/mucosal associated lymphoid tissue
Chronic Gastritis Type A (5As)
autoimmune autoantibodies pernicious anemia achlorhydria adenocarcinoma
Gastritis manifestations
mostly asymptomatic mild dyspepsia underlying condition can mask symptoms ab pain/upset burning sensation in chest/upper ab feeling of fullness bloating belching reflux severe: n/v gi bleed fever weight loss
Gastritis Acute tx
elimination of causative agent/exacerbating factors (ie h pylori)
meds to tx dyspepsia (PPI/histamine blocker)
surgery for gi bleed
chronic gastritis tx
elimination of causative agent/exacerbating factors (ie h pylori)
acupuncture
surgery for gi bleed
meds: sucralfate/misoprostol
chronic gastritis type A meds
abx and vitamin b12
chronic gastritis type B meds
1 week of triple therapy (amoxicillin, clarithromycin, PPI)
metronidazole if allergic to PCN
Gastric Outlet Obstruction
mechanical obstruction in pyloric region
causes
malignancy/surgical/interventional induced obstruction
Gastric Outlet obsruction s/s
ab pain distention bloating n/v dehyration weight loss early satiety
gastric outlet obstruction tx
benign: NG tube suction, meds to suppress gastric acid production, IV fluid/electrolyte replacement, nutritional supplementation, trial liquid diet, endoscopic balloon dilation or surgery
malignant: stenting, chemo, dilation, surgery
infantile hypertrophic pyloric stenosis
pylorus muscle hypertrophy > gastric outlet obstruction
unknown etiology
infantile hypertrophic pyloric stenosis s/s
begins 4-6 weeks of age
gradual onset of worsening non-bilious projectile vomiting
hunger/eagerness to feed after vomiting
dehydration/weight loss
peristalsis visible in upper abdomen
palpable mass may be present in right upper abdomen
hypochloremia hypokalemia metabolic alkalosis
infantile hypertrophic pyloric stenosis tx
surgery
gastric cancer
arises from gastric mucosa (adenocarcinoma 85%) or connective tissue of gastric wall/neuroendocrine tissue/lymphoid tissue
gastric cancer causes
h. pylori infection cigarette smoking high alcohol ingestion excessive dietary salt inadequate fruit/veggies pernicious anemia high-nitrate idet low incidence in US (high in korea/japan)
Gastric cancer s/s
most common: weight loss/ab pain mostly asymptomatic until too late dysphagia nausea early satiety occult GI bleed palpable ab mass
gastric cancer tx
radiation
chemo
surgical resection (gastrectomy)
prognosis poor: <20% 5 year survival
Absorption lower GI tract
chyme enters small bowel thru duodenum
Bowel primary site of absorption of
nutrients and vitamins
electrolytes
water
Osmotic Diarrhea
ex. lactose intolerance
large volume drawing water into lumen = hypotonic diarrhea w/out mucosal inflammation
Secretory diarrhea
ex cholera toxin
largevolume secondary to stim of cyclic amp mechanism for chloride secretion =
loss of chloride-rich isotonic fluid w/out mucosal inflammation
Inflammatory diarrhea
ex ulcerative colitis, crohn’s disease
low volume diarrhea w/ acute/chronic inflammation
= frequency &urgency = colicky pain
diarrhea tx
opiods/opioid derivatives
diphenoxylate slows peristalis) acts 45-60 min [moderate diarrhea]
loperamide (up to 16 mg/day, may lead to drowsiness)
Psyllium preperations (absorb large amounts of fluid = blukier stools w/ full glass of water)
use probiotic supplements w/ to correct altered GI flora
diphenoxylate w/ atropine
loperamide hydrochloride
antidiarrheal (slows peristalsis to allow more time for water reabsorption)
not recommended for infants
atropine offsets opioid affects (but anticholinergic effects @ higher doses)
SE: dizziness, drowsiness, may be habit forming (lomotil),
contra: severe liver disease, obstructive jaundice, dehydration/electrolyte imbalance, narrow-angle glaucoma
interx: CNS depressants
MAOI = HTN crisis
overdose: naloxone
Laxatives
promote evacuation of bowel
tx/prevents constipation
Cathartic Drugs
stronger/complete bowel emptying
prep for surgery/diagnostic procedures
used prophylactic after ab surgery
Bulk-Forming Laxative
calcium polycarbophil methylcellulose psyllium mucilloid contain fiber for chronic constipation must be taken with lots of water not used when rapid action needed
Saline Cathartic/Osmotic
lactulose
magnesium hydroxide
Miralax
sodium biphosphate
can produce BM very quickly (should not be used regularly)
possibility of dehydration and F/E depletion
used for colonoscopy prep/purging
Stimulant Laxatives
biascodyl
promote peristalsis by irritating bowel mucosa
rapid acting
causes diarrhea/cramping
can cause laxative dependence/depletion of F/E
Stool Softener/Surfacants
docusate
promotes water absorption in intestine
used to prevent constipation usually post-op
Herbal Agents
castor oil
senna
peristalsis by irritating bowel mucosa
Irritable Bowel Syndrome patho
ab discomfort w/ altered bowel habits
absence of any organic cause
visceral hypersensitivity frequent finding
intestinal inflammation w/ presence of lymphocytes/mast cells/proinflammatory cytokines
IBS- C (constipation) D (Diarrhea) M (mixed) U(Unclassified)
IBS etiology
can be stress/cns/psychologically related
unsure
typically 20-40 years old
usually female
IBS s/s
chronic/relapsing ab pain, bloating, changes in BM (ex diarrhea/constipation) cramps can be triggered after eating can include nausesa lethargy backache bladder symptoms
IBS TX
medication, education, lifestyle/diet changes
Diarrhea: anticholinergic meds (dicyclomine or hyscyamine)
Constipation: linaclotide (can lead to dependence)
Ulcerative Colitis
chronic inflammatory condition
mucosal layers of colon
continuous lesion can extend into proximal colon
remitting inflammation
bowel changes: epithelial damage, crypt abscesses, loss of goblet cells
Crohn’s Disease
chronic inflammatory condition involves any part of GI tract transmural inflammation of bowel skip lesions inflamm/destruction of bowel
Inflammatory Bowel Diseases
UC and Crohn’s
Ulcerative Colitis s/s
fever loss of appetite weight loss fatigue night sweats bloody/mucoid diarrhea dehydration anemia crampy ab pain pain w/ defecation toxic megacolon (needs blood tranfusion or surgery)
Crohn Disease s/s
fever loss of appetite weight loss fatigue night sweats nause vomiting diarrhea w/ or w/out blood ab pain pain with defecation
Crohn Disease complications
bowel strictures
obstructions
perforations
intraabdominal abscesses
IBD etiology
not completely understood females > males whites CD: bimodal peaks 10-30 then 50-70 UC: peaks 20-30 years [more common]
IBD TX
optimize quality of life by tx acute process
nutrition
healthy lifestyle
anti inflammatory agents (5-aminosalicylic acid/corticosteroids)
immunosuppressants (cyclosporine, methotrexate, theopurines)
anti-tumore necrosis factor agents
ABX
probiotics
surgery
Extraintestinal symptoms of ulceratie colities
episclerities (red streak through eye) kidney sontes fistulae UTI pyoderma grangrenosum (skin lesion) phlebitis peripheral arthritis steatosis gallstones lesions on tongue
Bowel Obstruction
usually in small bowel
Bowel obstruction complications
strangulation
bowel necrosis
perforation > sepsis > death
Bowel obstruction etiology
HANG IV
usually due to adhesions hernia adhesions neoplasm/tumor gallstone ileus intussusception volvulus
bowel obstruction s/s
hyperactive, high-pitched bowel sounds absent bowel sounds if ileus develops ab pain n/v ab distention inability to pass gas/stool
bowel obstruction tx
gastric decompression (NG) w/ IV fluids surgery if strangulation/bowel ischemia = emergency surgery
Herniation
protrusion of intestinal contents thru hole in abdominal wall
Volvulus
twisting of bowel & mesenteric root > intestinal obstruction & ischemic necrosis of twisted intestinal loops
Intussusception
segment of intestines grow on top of each other (usually 0 -18 months)
Hirschsprung Disease
congenital agonglionic megacolon no meconium when born no ganglion cells in rectum/sigmoid colon causes intestinal obstruction constipation/ab distention/vomiting males > females associated w/ Down syndrome dx: imaging/biopsy tx: resection of affected segment
Celiac Disease
gluten-sensitivity severity varies immune-mediated increased lymphocytes, epithelial proliferation w/ crypt elongation TX: gluten-free diet and products
Diverticular
small outpouchings (herniations) colonic mucosa protrude thru muscle layers of colon wall
diverticulosis
diverticula w/out evidence of inflammation
diverticulitis
inflamed diverticula
Diverticular Disease
usually @ where feeder artery penetrates thru colon wall (can become compressed/eroded)
low grade inflammation
mucosal herniation b/c of contractions @ area of weakness
Diverticular disease complications
inflammation w/ abscess fistula (connection where there shouldn't be ex bowel to skin) obstruction bleeding perforation
Diverticular Disease causes
low-fiber diet NSAID use advanced age obesity lack of exercise
Diverticular Disease s/s
sudden, constant ab pain in LLQ ab distention/nausea diarrhea constipation decreased appetite fiver tachycardia hypotension
Diverticular Disease TX
outpatient: clear liquid diet, broad spectrum ABX
inpatient: [required if suspected peritonitis] IV fluids, ABX, NPO
surgery
Meckel’s Diverticulum
sac-like outpouching of small intestine wall at birth in distal ileum
2% of pop
@ in in length
2 ft from ileocecal valve
2% are symptomatic
if symptomatic (painless rectal bleeding > obstruction) = surgery
Hemorrhoids
abnormal engorgement of vascular mucosal cushions
internal or external
hemorrhoids causes
straining during bm
increased intraab pressure
pregnancy
portal HTN
hemorrhoids s/s
hematochezia (blood from anus) itching perianal discomfort soiling Large: rectual fullness feeling, incomplete evacuation
hemorrhoids tx (stageI/II and III/IV)
diet changes, topical glucocorticoids, vasoconstrictors, analgesics, sclerotherapy
hemorrhoidal banding, hemorrhoidectomy
Adenomas
polyps
precursor to most colorectal cancers
form in glandular structures of intestinal mucosal epthelium
colon cancer
in ascending/transverse/descending colon
rectal cancer
15 cm from anus
colorectal cancers s/s
EARLY: usually asymptomatic hematochezia anemia changes in BM habits weight loss fatigue ab pain
colorectal cancer modifiable risk factors
obesity sedentary lifestyle smoking mod - heavy alcohol intake ^ red/processed meats low fruit/veggie intake
colorectal cancer hereditary/medical risk factors
family history IBD genetic factors (lynch syndrome) Type 2 DM Aging
colorectal cancers protective factors
whole-grain fiber diet
use of aspirin
colorectal cancers screening
colonoscopy
occult blood
appendicitis
obstruction thought to lead to bacterial overgrowth/distention/inflammation
appendix can become gangrenous and rupture
cause not truly understood
tx: surgery
appendicitis s/s
cramping ab pain, tenderness w/ palpation of RLQ, n/v, increased WBC, low grade fever
