What is the normal volume and frequency of flatus?
Volume: 500-1500ml/day
Frequency: 6-20 times/day
Gases with little odor are derived from _____
Plant carbohydrates (hydrogen and methane)
Gases that are malodorous are derived from ______
Meat and eggs (sulfur dioxide)
Excessive amounts of flatus may be an indication of ________
Malabsorbtion
What are some treatment methods for GI gas?
-Lactose-free diet
-Avoid common gas-producing foods
-"Beano" -> reduces gas associated w/beans
What do patients commonly use the term "diarrhea" to refer to?
-increased frequency of bowel movements
-increased stool liquidity
-a sense of fecal urgency
-fecal incontinence
What is the official definition of diarrhea?
-> Increase in stool weight >200 gm/day that may be associated with increased liquidity, stool frequency, perianal discomfort, and urgency with or without fecal incontinence
Acute, persistent, and chronic diarrhea are classified by what time frames?
Acute < 2 weeks
Persistent 2-4 weeks
Chronic >4 weeks
What volume of liquid passes through the ligament of Treitz each day?
9-10L of fluid
How much does the Jejunum absorb?
Approx. 6 L
How much does the Ileum absorb?
Approx. 2.5 L
How much fluid passes through the colon each day, how much is absorbed by the colon, and how much is left in the feces?
-1.5 L passes through colon
-Colon absorbs more than 90% of this load
-Approx 0.1 L is left in the feces
The overall absorptive efficiency for water is 99%. Why is it important to know this, as well as possible reduction in efficiency?
Reduction of this efficiency by as little as 1% may lead to diarrhea.
Name some causes of acute diarrhea.
-Infectious agents -Bacterial toxins
-Drugs -Community outbreaks (viral, food)
-Day care or swimming (protozoal)
-Antibiotic-associated (C. Diffcile colitis)
-Sexually transmitted
-Traveler's diarrhea
What is part of the Acute Diarrhea evaluation process?
-Distinguish between mild and serious illness
-For > 7 day duration: check stool culture, O & P, fecal leukocytes
-Bloody diarrhea, fever, abd pain: Work-up
-Physical exam: Tilts, addt'l tests depending on history
What are the four ways of treating acute infectious diarrhea?
-Diet: rest bowels -> avoid high-fiber foods, fats, milk products -> take in easily digestible foods
-Rehydration: Oral rehydration is best.
-Anti-diarrheal agents
-Antibiotic therapy -> for select patients
What is the BRAT diet?
Bananas, Rice, Applesauce, Toast
Why is the BRAT diet effective?
These foods are low in fiber and digestive residue.
What do you need to rule out during chronic diarrhea evaluation?
-acute diarrhea causes
-lactose intolerance
-previous gastric surgery
-parasites
-medications
-systemic disease
True or false: During chronic diarrhea evaluation, you should perform a physical exam, to include an abdominal exam.
True
What tests should be performed during a chronic diarrhea evaluation?
-Fecal leukocytes, stool culture, O & P
-CBC, electrolytes, LFTs, albumin, TSH
-Flex sig or C-scope w/biopsy
-UGI, BE
What are some causes of chronic diarrhea?
-Osmotic -Secretory
-Inflammatory -Malabsorption syndromes
-Motility disorders -Chronic infections
-Irritable bowel
What is the main clue for osmotic chronic diarrhea?
-Stool volume decreases with fasting
What are the causes for osmotic chronic diarrhea?
-Medications: antacids, Lactulose, sorbitol
-Disaccharides deficiency- Lactulose intolerance
-Factitious diarrhea - magnesium use
What is the main clue to indicate secretory chronic diarrhea?
-Large volumes (>1 L/day) -> little change with fasting
What are the causes of secretory chronic diarrhea?
-Hormonal: Carcinoid, ZE, thyroid ca
-Medications
-Factitious diarrhea - laxative abuse
-Villous adenoma
-Bile salt malabsorption (post-op, Crohn's)
-Celiac Sprue
What are the main clues for inflammatory chronic diarrhea?
-fever
-hematochezia
-abdominal pain
-> Systemic symptoms/signs: arthralgias, rash
What are the causes of inflammatory chronic diarrhea?
-ulcerative colitis
-Crohn's disease
-Malignancies - lymphoma, adenoma
-Radiation enteritis
What are the main clues for malabsorption chronic diarrhea?
-weight loss
-fecal fat
What are the causes for malabsorption chronic diarrhea?
-Small bowel mucosa disease: Sprue, Crohn's, Whipple's, short bowel syndrome