Clinical Care of the Gastrointestinal System Flashcards
Diarrhea in an acute onset typically lasts less than ____ weeks and is most commonly caused by what?
2 weeks.
Infectious agents, bacterial toxins
How can infectious sources be transmitted, and what is their typical incubation period?
Fecal-oral contact, food and water
12-72 hours
Where does liquid feces move from to turn into well-formed solid stool?
> 90% of water is absorbed in the small intestine. The remaining water reaches the colon, transforms into liquid feces in the CECUM, and then turns into solid stool in the RECTOSIGMOID.
Disorders of what part of the intestines result in increased amounts of diarrheal fluid, and greater loss of water, electrolytes and nutrients?
Small intestine
This is a form of gastroenteritis caused by infectious agents and commonly seen in an operational setting. How is it defined?
Acute gastroenteritis
-Defined as three or more episodes a day or at least 200g per day.
-Rapid onset that lasts <2 weeks.
-May be accompanied by N/V, fever, and/or abdominal pain.
What is a common physical finding of a patient with acute viral gastroenteritis?
Mild diffuse abdominal tenderness
Soft abdomen with voluntary guarding
What are common infectious agents seen in acute infectious gastroenteritis?
Adherence, mucosal invasion, enterotoxin production, cytotoxic production
What are two common causes of gastritis?
Chronic NSAID use and chronic/large amounts of alcohol consumption
What is required to diagnose gastritis?
Histopathologic evidence of inflammation
What are the classifications of chronic diarrhea?
Osmotic
-Increased osmotic load, seen in medication use and Zollinger-Ellison syndrome
Inflammatory
-Inflammation of the mucosal lining of the intestine, like with IBD or malignancy
Secretory
-When secretions be secreting
Chronic infections
-Giardia Lamblia
Malabsorption syndromes
-Celiac, Whipple, Crohn’s, Lactose Intolerance
Motility disorders
-IBS
Inflammatory diarrhea suggests involvement of what organ by invasive bacteria, parasites, or toxins?
Colonic involvement
What do patients complain of in acute infectious diarrhea?
Bloody stool! Frequent, small volume bloody stool associated with fever, abdomen cramps, tenesmus, and fecal urgency.
What are common causes of acute infectious diarrhea?
Shigella, Salmonella, E. coli, E. coli O157:H7, Entamoeba histolytica
Community outbreaks suggest viral etiology or common food source
Recent illness in family suggests infectious origin
Ingestion of improperly stored/prepared food suggests food poisoning.
This type of diarrhea is generally milder and is caused by viruses or toxins that affect the small intestine.
Acute non-inflammatory diarrhea
Non-bloody in nature.
They interfere with salt and water balance, resulting in large volume watery diarrhea, often with N/V and cramps.
What are common causes of acute non-inflammatory diarrhea?
Viruses, enterotoxin-producing E. coli, Giardia Lamblia, crytosporidium, cyclospora
In food poisoning caused by a preformed toxin, the incubation period will be how long, and what will the major complaints be?
Short (1-6 hours after consumption)
Vomiting, fever is usually absent
In food poisoning where the organism is already present but the toxin hasn’t been produced in the food at time of consumption, what will your typical incubation period be? What will your complaints be?
Longer (8-16 hours)
Vomiting is less prominent. Abdominal cramping is frequent. Fever is absent.
Over 90% of patients with acute non-inflammatory diarrhea responds within __ days to what type of treatment?
5 days
Rehydration therapy or antidiarrheal agents (it is a self-limiting condition)
If diarrhea worsens or persists for __ days or more, what should be done?
7
Send stool sample for fecal leukocyte, ovum and parasite evaluation, and bacterial culture.
Prompt medical evaluation is indicated in what situations (diarrhea)?
Signs of inflammatory diarrhea
-Fever >38.5 C)
-Bloody diarrhea
-Abdominal pain
Six or more unformed stools in 24 hours
Profuse watery diarrhea or s/s of dehydration
For patients with diarrhea, hospitalization is required in what situations?
Severe dehydration, toxicity, marked abdominal pain
Send fecal sample for bacterial culture
Symptoms of diarrhea with a sudden onset
N/V and decreased appetite
Crampy abdominal pain
Loose stool
Malaise
Fatigue
Stool examination for Giardia Lamblia is important for what situations?
Waterborne and food borne disease outbreaks, daycare center outbreaks, illness in international travelers
Oral rehydration of a patient with diarrhea can be accomplished with what liquids?
Fluids containing glucose, Na+, K+, Cl-, and bicarbonate or citrate
A convenient mixture of 1/2 tsp salt, 1 tsp baking soda, 8 tsp sugar, and 8 tsp OJ diluted to 1L with water can be used.
Avoid high fiber foods, fats, dairy, caffeine and alcohol.
Oral electrolytes can be used alternatively, given at a rate of 50-200 mL/kg/24h.
What antidiarrheal medications can be used to treat a patient?
Loperamide
-4mg, 2mg after every loose stool, max dose of 16mg/day.
-Do not use in patient with infectious diarrhea or prolonged QT interval
Bismuth
-2 tablets/30mL PO q 30-60 min PRN, max 16 tablets/240mL/24 hours
-Produces black stool, educate your patient.
What infectious bacteria and parasites indicate the use of empiric antibiotic therapy?
Shigellosis, cholera, salmonellosis, listeriosis, C. difficile.
Amebiasis, giardiasis, cryptosporidiosis
This is a condition with histologic evidence of inflammation of the epithelial or endothelial lining of the stomach.
Gastritis
Categorized into 3 types:
-Erosive and hemorrhagic
-Non-erosive and non-specific
-Specific
How is erosive and hemorrhagic gastritis typically diagnosed?
Endoscopically, typically because a patient complains of dyspepsia or upper GI bleeding
What types of patients typically present with gastritis?
Alcoholics, critically ill patients, patients taking NSAIDs
Common causes are drugs, alcohol, stress, and portal hypertension
Common symptoms of gastritis
Epigastric pain, N/V, hematemesis (nonspecific bleeding)
Upper GI bleeding with “coffee grounds” emesis or bloody aspirate on NG tube
What are the typical lab findings on a patient with gastritis?
Low HCT due to significant bleeding (if it occurred)
Iron deficiency
H. pylori testing
Fecal occult blood
What is the most sensitive method (“Gold Standard”) to diagnose gastritis?
Upper endoscopy
Usually performed within 24 hours for patients with upper GI bleeding
How do you treat a patient with NSAID gastritis?
Discontinue NSAIDs, reduce to lowest dose or administer NSAIDs with meals.
Give PPI for 2-4 weeks.
How do you treat a patient with alcoholic gastritis?
Discontinue alcohol use.
Give H2 receptor antagonist, PPI, or sucralfate for 2-4 weeks.
What are the common causes of non-erosive, non-specific gastritis?
H. pylori infection
Pernicious anemia
Eosinophilic gastritis
How can you test for non-erosive, non-specific gastritis due to H. pylori?
Histology via endoscopy, or serology
Serology is not helpful in patients with previous H. pylori infectious due to presence of antibodies.
What three coordinated things occur during defecation?
Coordinated colonic peristalsis, rectal contraction, and early anal relaxation.
What are the multifactorial causes of constipation?
Diminished intake of fiber and fluids (most common)
Systemic diseases
Medications
Structural abnormalities
Slow colonic transit
IBS-C
Hirschsprung disease
What do patients experiencing constipation complain of?
Infrequent stool
Excessive straining
Sense of incomplete evacuation
Need for digital manipulation
What are the first line treatments of constipation?
Dietary changes and exercise regimen.
Increased water intake.
Fiber supplementation.
-Usually no immediate response, increase doses over 7-10 days.
What are the second line treatments of constipation?
Stool softeners or laxatives.
Emollients such as Docusate sodium
-100mg daily to twice daily
Stimulants such as Bisacodyl
-5-15mg daily or 10mg TID
What are the third line (last resort) treatments of constipation?
Suppositories or enemas.
Examples include glycerin suppository or fleet enemas.
When may fecal disimpaction be necessary?
Obstipation or constipation refractory to treatment. Complicated/chronic cases should be referred to gastroenterology.
Where are internal and external hemorrhoids located? Describe each.
Internal: above the dentate line.
-Subepithelial cushions of the anorectum comprised of submucosa and muscularis.
-NO NERVOUS INNERVATION.
External: below the dentate line.
-Arise from inferior hemorrhoidal veins, covered with squamous epithelium.
-INNERVATED WITH NERVES - PAINFUL WHEN THROMBOSED
What structure of the anus provides a water tight closure of the anal canal?
Hemorrhoidal venous/vascular cushions.
What three primary locations do internal hemorrhoids occur in?
Right anterior
Right posterior
Left lateral
What is unique about the pain level of internal hemorrhoids?
They lack a nerve supply so they are not painful when present.
These hemorrhoids occur below the dentate line and are painful when thrombosed.
External hemorrhoids
What results when hemorrhoids become symptomatic due to pressure?
They become distended, engorged and they bleed.
This condition occurs due to thrombosis of the external hemorrhoidal plexus, and typically occurs in healthy adults due to coughing, heavy lifting and straining.
Perianal hematoma.
This condition is characterized by acute onset of an exquisitely painful, tense and bluish perianal nodule covered with skin that may be up to several centimeters in size.
Perianal hematoma
The pain is most severe in the first few hours but gradually eases over 2-3 days as edema subsides.
What are the physical findings seen in an internal hemorrhoid?
Painless bleeding, prolapse, mucoid discharge.
Bleeding can be streaks of blood or drips in the toilet.
Describe the 4 stages of internal hemorrhoids.
Stage I: Dilated, confined to the anal canal.
Stage II: Prolapsed during straining, reduces spontaneously.
Stage III: Prolapse, requires manual reduction.
Stage IV: Chronically prolapsed.
This condition may result in a sense of fullness or discomfort and mucoid perianal discharge resulting in irritation and soiling of underclothes.
Chronic prolapsed hemorrhoids.
For a thrombosed external hemorrhoid, if seen within the first __-__ hours, removal of what may help relieve your patient?
24-48 hours
Removal of the clot.
When removing the clot of a thrombosed external hemorrhoid, how will you anesthetize your patient?
Anesthetize the skin around and over the lump with 1% lidocaine using a tuberculin syringe with a 30 gauge needle.
Most patients with stage I and II hemorrhoids can be managed with what?
Conservative treatment.
For edematous and prolapsed hemorrhoids, gentle manual reduction can be supplemented with what?
Suppositories
Topical witch hazel
Warm sitz baths
*Surgical excision is reserved for 5-10% if patients with chronic severe bleeding due to stage III or IV hemorrhoids.
What is the definitive treatment for internal hemorrhoids? How is it done?
Rubber band ligation (surgical banding)
A specialist places a rubber band around the base of an internal hemorrhoid to restrict blood flow.
This is ONLY done on INTERNAL hemorrhoids due to the lack of nerve innervation.
These are linear, rocket shaped ulcers that are typically <5mm in length.
Anal fissures.
Where do anal fissures normally occur?
The posterior midline (6 o’clock), but 10% occur anteriorly (12 o’clock, toward the genitals).
Fissures away from the midline should be concerning for serious diseases or assault.
This condition has severe, tearing pain during defecation followed by throbbing discomfort.
Anal fissures.
The pain may lead to constipation due to the fear of pain.
How do acute and chronic fissures appear during inspection?
Acute: like cracks in the epithelium.
Chronic: fibrosis and skin tags at the outermost edge.
What are your treatment options for anal fissures?
Goal is to promote effortless, painless BMs.
-Fiber supplements and sits baths.
-Topical anesthetics.
-Oral analgesics
-Tylenol
-NSAIDs
In 45% of patients with anal fissures, healing occurs within 2 months with conservative management to include:
Sitz baths, fiber intake, stool softeners.
Chronic fissures should be referred and may be treated with topical nitroglycerin, diltiazem, or botulinum injections.
This condition is frequently encountered in the perianal and perirectal regions, and almost always begins with involvement of an anal crypt and its gland.
Anorectal abscess.
What spaces can anorectal abscesses occur? What are the most and least common areas?
1) Perianal space (most common)
2) Intersphincteric space
3) Ischiorectal space
4) Deep postanal space
5) Supralevator/pelvirectal space (least common)
What is a common sequela of anorectal abscesses?
Fistulas.
This condition presents with a dull, aching, or throbbing pain that becomes worse immediately before defecation, is lessened after defecation, but persists between BMs.
Anorectal abscesses.
The pain is significantly increased by the pressure in the rectum just before defecation.
What is the treatment of a perianal abscess?
Treatment is surgical and should be done immediately before the abscess becomes fluctuant.
All perirectal abscess drainage should be done in the OR.
Isolated, simple, fluctuant perianal abscesses can be done in the ED or outpatient.
Patients with an abscess and accompanying fever, leukocytosis, valvular heart disease, or cellulitis should be prescribed what?
Cephalexin 250mg PO QID or doxycycline 100mg BID for seven days
This chronic condition occurs when an anal abscess is ruptured or drained and an epithelialized track is formed that connects the abscess in the anus or rectum with the perirectal skin.
Anorectal Fistula (or “Fistula-in-Ano”)
What are the symptoms of an anorectal fistula?
Nonhealing anorectal abscess following drainage.
Chronic purulent drainage and a pustule like lesion in the perianal or buttock area.
Intermittent rectal pain.
Intermittent malodorous perianal drainage and pruritus.
Antibiotics should be given to a patient with an anorectal fistula based on what?
Clinical judgement (typically the proximity of the involved area, patient stability, etc.)
This condition ranges from asymptomatic hair-containing cysts and sinuses to large abscesses of the sacrococcygeal region.
Pilonidal disease
Pilonidal abscesses can occur due to S. aureus invading through the openings caused by ingrown hairs.
What anatomical area do pilonidal cysts and sinuses most often occur?
The sacral area superior to the gluteal fold.
(TG: midline in the upper part of the natal cleft overlying the lower sacrum and coccyx)
A patient presents with complaint of swelling, pain, persistent discharge, and a tender mass in the sacral area. What is the diagnosis?
Abscessed pilonidal sinus/cyst
What is the treatment of choice for pilonidal disease? What is the definitive treatment for recurrent infections?
Surgical treatment. For abscessed cysts in the superior gluteal crease, perform I&D. Recurrences are common.
Recurrent infections and drainage are better treated with a complete excision of the area that can be performed 6 weeks after an active infection.
Ulcerative colitis and Crohn’s disease are two diseases known as what term?
Inflammatory Bowel Disease
This disease causes inflammation to the colonic mucosa, and can have pseudo-polyps.
Ulcerative colitis
*UC can be cured whereas Crohn’s cannot
This is an island of normal colonic mucosa which only appears raised because it is surrounded by atrophic tissue.
Pseudo-polyp seen in ulcerative colitis.
This disease can affect any segment of the GI tract. Skip lesions will appear all over the GI tract in segments. What is it and what kind of inflammation does it cause?
Crohn’s disease. It causes transmural inflammation which can form fistulas.
Which of the IBDs will be more likely to have extra-intestinal manifestations?
Crohn’s
What is the difference between the way Crohn’s and Ulcerative Colitis affect the layers of the GI tract?
Crohn’s: transmural inflammation, which is complete inflammation of all layers of the bowel wall.
UC: Involves only the mucosal layer of the bowel wall.
What is the most common portion of the GI tract that Crohn’s affects, and what does it cause?
The terminal ilium, which results in malabsorption of vitamin B12, bile salts and calcium.
*B12 deficiency causes a macrocytic anemia with neurological symptoms.
Crohn’s can affect ANY SEGMENT of the GI tract and will develop “skip lesions.”
What should a clinician take note of when assessing a patient for Crohn’s?
Fevers
Patient’s sense of well-being*
Weight loss*
Abdominal pain
Number of liquid BMs per day*
Surgical/Hospitalization history
What is the most common finding in a patient with Crohn’s, and when they have diarrhea how will it appear?
Ileitis or ileo-colitis is the most common finding.
Diarrhea will be NON-bloody in nature.
Intra-abdominal masses are also common (often due to the formation of an abscess).
Small bowel obstruction is a complication of what disease? What are its signs and symptoms?
Crohn’s disease.
Abdominal distention, N/V, intermittent liquid stools and/or constipation, postprandial bloating, cramping pain, loud borborygmi.
A patient reports “peeing out air.” What is the disease process, and what is the complication that is causing this symptom?
Crohn’s disease. Fistula to the bladder due to a sinus track formation is the complication.
1/3rd of patients with large or small bowel involvement secondary to Crohn’s disease will develop ____ disease. What are the signs and symptoms of this complication?
Perianal disease.
-Large painful skin tags
-Anal fissures
-Perianal abscesses
-Perianal fistulas
During acute exacerbations of Crohn’s disease, what modality should be used to assess for abscess or fistula formation?
CT scan of the abdomen
Crohn’s disease puts a patient at increased risk for developing what?
Colon carcinoma. Screening colonoscopy to detect dysplasia or cancer is recommended for patients with a history of 8 or more years after initial flare/diagnosis.
Patients with Crohn’s are 20 times more likely to develop colon cancer than the general population.
This is an inflammatory condition that only involves the mucous of the large intestine, but can involve the rectum, and the inflammation manifests in a continuous fashion.
Ulcerative colitis.
Inflammation of the colon seen in ulcerative colitis can cause what issues/complications?
Bleeding seen in the feces
Ulcerations, edema, fluid and electrolyte loss
What are the 3 areas of the colon that are most commonly affected in ulcerative colitis, and what percentage of patients does each affect?
33%: recto-sigmoid region
33%: splenic flexure (left sided colitis)
33%: proximal (extensive colitis)
*It is more common in non-smokers and former smokers.
*Appendectomy before the age of 20 for acute appendicitis is associated with a reduced risk of UC.
What pertinent history should be asked about a patient with ulcerative colitis?
Stool frequency and character
The presence and amount of rectal bleeding
Diffuse crampy abdominal pain
Fecal urgency
Tenesmus (consistent urge to defecate)