Transcript Airgas template

Chapter 28
Disorders of Gastrointestinal
Function
Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins
The Job of the Bowel
• To digest food: involves a corrosive solution
and potentially pathogenic bacteria
• To absorb the food into the blood while
keeping the corrosive substances and the
bacteria inside the gut
• To keep the solution moving down the bowel
at the right rate for digestion and absorption
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Inflammation and Damage to the Bowel
Wall
• Hemorrhage  anemia
• Perforation  peritonitis
• Decreased mucosal function  malabsorption
• Decreased bacterial containment  sepsis
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Hemorrhage
• Hemorrhage above the stomach: frank
hematemesis
• Hemorrhage into the stomach with partial
digestion of blood: coffee-grounds vomitus
• Hemorrhage in the intestine with blood mixing
into stools: occult blood
• Hemorrhage into the intestine with large
volumes of blood: melena
• Hemorrhage in the rectum: red blood coating
stools
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The Vicious Circle: One Kind of Bowel
Problem Can Cause Another
Inflammation
and cell damage
Reflex paralysis
Obstruction
Distension, ischemia
Food does not
pass through
bowel at correct
rate
Decreased
bowel
function
Malabsorption
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Question
Which symptom accompanies hemorrhage into the
stomach?
a. Hematemesis
b. Occult blood
c. Coffee-grounds vomitus
d. Melena
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Answer
c. Coffee-grounds vomitus
Rationale: Coffee-grounds vomitus is a classic symptom
of blood in the stomach (it mixes with chyme to give it
the coffee-grounds color and consistency). Hematemesis
occurs in hemorrhage above the stomach; occult blood
is the result of blood mixing with stool in the small
intestine; and melena occurs with large-volume
hemorrhages in the intestine.
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Disorders of the Esophagus
• Dysphagia
• Achalasia
• Esophageal diverticulum
• Gastroesophageal reflux disease
• Cancer of the esophagus
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Disorders of the Stomach
• Acute gastritis
• Chronic gastritis
• Ulcer disease
– Peptic ulcer
– Zollinger-Ellison syndrome
– Stress ulcers
• Cancer of the stomach
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Scenario
Mrs. D. has pain in her stomach at night and vomits
up blood.
• She is pale and weak
• The doctor finds that her hematocrit is low
• Her blood contains large, pale erythrocytes and
some reticulocytes
• Bilirubin levels are normal
Question:
• Explain her symptoms
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H.
pylori
Helicobacter Pylori
• The major
cause of
ulcers
• Second most
common
cause is
NSAIDs
damages
stomach
lining
ULCER
repair and
healing
increased risk of
gastric cancer
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“In the US: The frequency of HP infection may
be linked to race. White persons account for
29% of cases, and Hispanic persons account for
60% of cases.”
“Internationally: … At least half of all people
are infected … HP may be detected in
approximately 90% of individuals with peptic
ulcer disease...”
(Santacroce, L., and Miragliotta, G. 2005. Helicobacter pylori infection. eMedicine.
Retrieved April 2005 from http://www.emedicine.com/med/topic962.htm#top.)
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Inflammations of the Small and Large
Intestines
• Infectious enterocolitis
– Viral infections
– Bacterial infections
• Inflammatory bowel disease
– Crohn disease
– Ulcerative colitis
• Diverticular disease
• Appendicitis
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Discussion
Think back to the last time you had enterocolitis.
Questions:
• List the things that happened to you
• Which of them were systemic signs of
inflammation?
• Which of them were caused by your sympathetic
system?
• Which of them helped you get over the disease?
• Which of them could have caused serious
complications?
• Why?
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Question
Which intestinal disorder is an autoimmune disease?
a. Enterocolitis
b. Crohn disease
c. Ulcerative colitis
d. Diverticulitis
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Answer
b. Crohn disease
Rationale: Crohn disease is an autoimmune disorder that
affects the mucous membrane lining of the bowel (it gets
thicker and doesn’t function as it should), causing chronic
malabsorption.
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Enterocolitis
• The bowel attempts to get rid of the infectious agent
– Exudate to dilute toxins
– Hypermotility
• Vomiting
• Decreased intestinal function
– Food not absorbed
º Osmosis draws water into the bowel
º Osmotic (or explosive) diarrhea
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Inflammations That Cannot Be Expelled
• Pain and sympathetic nervous stimulation cause the
bowel to freeze in position
– Reflex paralysis or paralytic ileus
• Muscles of the abdominal wall tighten to protect the
inflamed bowel
– Board-like abdomen
• Diaphragm and accessory breathing muscle
movements decrease
– Shallow breathing
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One Kind of Bowel Problem Can Cause
Another
Inflammation
and cell damage
Reflex paralysis
Obstruction
Distension, ischemia
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Intestinal Obstruction
• Mechanical
– Severe, colicky pain
– Borborygmus
– Audible, high-pitched peristalsis; peristaltic rushes
– Awareness of intestinal movements
• Paralytic
– Continuous pain
– Silent abdomen
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Results of Obstruction
• Vomiting  fluid and
electrolyte loss
• Fluids move into
intestinal contents
• Gas accumulates
• Distension of bowel
• Compartment
syndrome  ischemia,
necrosis
• Anaerobic bacteria
produce endotoxin 
toxemia
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Question
Tell whether the following statement is true or false.
Paralytic intestinal obstruction causes audible paralysis.
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Answer
False
Rationale: Mechanical obstruction results in high-pitched
peristalsis (bowel sounds); in paralytic obstruction, bowel
sounds are inaudible (silent abdomen).
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Bowel Distension and Compartment
Syndrome
• The blood vessels
on the surface of
the gut are
covered and held
in place by the
inflexible
mesentery
• When the gut
lumen distends, it
crushes the blood
vessels between
the gut wall and
the mesentery
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Compartment Syndrome
• An organ expands inside a membrane that
will not expand
• The blood vessels feeding the organ are
crushed between the organ and the
membrane
• Blood supply is cut off
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Scenario
Mrs. K. presents with acute abdominal pain.
• She has a distended, board-like abdomen with no bowel
sounds. Blood pressure is low and heart rate elevated. Her
skin is pale and cool with cold sweat. She is very restless
and complains of acute abdominal pain.
• The pain came on over the last 8 hours. WBC count is
elevated. Now she complains of nausea and begins throwing
up, but there is no blood in her vomitus. She has had no
bowel movements or urine production.
Question:
• What adaptive responses and counterattacks are evident?
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Scenario (cont.)
• Mrs. K. has begun to run a fever
• Her skin is now flushed and warm, and her
abdomen is further distended
• Her blood pressure has decreased further
• The doctor has ordered nasogastric suction and
an isotonic IV
Question:
• Why are you taking fluids out of her GI tract
and putting them into her veins?
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Alterations in Intestinal Absorption
• Malabsorption syndrome
• Celiac disease
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