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GASTROINTESTINAL SYSTEM
CH 16 Goodman
Upper GI (mouth, esophagus, stomach and duodenum) - ingestion and digestion
Lower GI: small intestines - digestion, absorption of nutrients; large intestines – absorbs water and electrolytes, stores waste products until elimination
Enteric nervous system - just as many nerves as the spinal cord; can function completely independent of the CNS; it is thought that the “brain in the bowel” can have its own form of neuroses (such as functional bowel syndromes)
PT needs to be aware of the clinical manifestations of GI issues - many have implications on physical activity tolerance and healing / recovery (dehydration, malnutrition, anemia)
INTRODUCTION
Gastrointestinal SystemMouth>pharynx>esophagus>stomach>small intestine
(duodenum, jejunum, ileum)>large intestine (cecum, ascending, transverse, descending, sigmoid)
>rectum>anus**liver, gallbladder and pancreas needed for digestion
Liver The liver has multiple functions, but two of its main functions within the digestive system are to make and secrete an important substance called bile and to process the blood coming from the small intestine containing the nutrients just absorbed. The liver purifies this blood of many impurities before traveling to the rest of the body.
Additional organs of digestion
Gallbladder The gallbladder is a storage sac for excess bile. Bile made in the liver travels to the small intestine via the bile ducts. If the intestine doesn't need it, the bile travels into the gallbladder, where it awaits the signal from the intestines that food is present. Bile serves two main purposes. First, it helps absorb fats in the diet, and secondly, it carries waste from the liver that cannot go through the kidneys.
Additional organs of digestion
Pancreas Among other functions, the pancreas is the chief factory for digestive enzymes that are secreted into the duodenum, the first segment of the small intestine. These enzymes break down protein, fats, and carbohydrates.
Additional organs of digestion
Aug. 21, 2009 — The lowly appendix, long-regarded as a useless evolutionary artifact, won newfound respect two years ago when researchers at Duke University Medical Center proposed that it actually serves a critical function. The appendix, they said, is a safe haven where good bacteria could hang out until they were needed to repopulate the gut after a nasty case of diarrhea, for example.
*Has been regarded as a vestigial structure (one that has lost all or most of its original function through evolution)
www.sciencedaily.com
Evolution of the appendix…in case you were wondering
Nausea (symptom) uneasy feeling - as if going to vomit -
caused by irritation in nerve ending of stomach
Signs and symptoms of Gastrointestinal Disease
Vomiting (sign) Flow of stomach contents backwards through upper
GI......and either aspirated into lungsor out the mouth (if back down the esophagus is technically just reflux)
Caused by anything that causes nausea Complications include fluid and electrolyte imbalances,
pulmonary aspiration --> aspirationpneumonia; malnutrition; rupture of esophagus; dental decay (if prolonged)
If vomit is blood mixed with stomach acids looks like “coffee-grounds” and is aptly referred to as “coffee-ground vomit”
Signs and symptoms…
Diarrhea (sign) Abnormal fluid mixture, frequency and/or
volume of stool Results in poor absorption of fluid, nutritive
elements, and electrolytes
Signs and symptoms
Anorexia (symptom vs. sign) Diminished appetite or aversion to food
Anorexia - Cachexia (sign) Anorexia that results in wasting of muscle;
is a common systemic response to cancer Associated with poor intake and high
metabolic rate
Signs and symptoms
Constipation (sign) Fecal matter is too hard to pass easily; or
when bowel movements are so infrequent that discomfort and other symptoms interfere with daily activities
May occur due to diet, dehydration, side effect of medication, acute or chronic disease of digestion system, inactivity or prolonged bed rest, emotional stress
Signs and symptoms
Dysphagia (sign vs. symptom) Difficulty swallowing that results in the
sensation that food is stuck somewhere in thethroat or chest; may be a symptom / sign of many other disorders other than GI - such asneurological conditions
Signs and symptoms
Achalasia (sign vs. symptom) Rare disorder that makes it difficult for food
and liquid to pass from esophagus to stomach.
Due to loss of nerve cells in the esophagus so that food is not propelled down the GI tract
Also, the lower esophageal sphincter (LES) which connects the esophagus and the stomach doesn’t fully relax.
This results in a feeling of “fullness” in the sternal region that can progress to dysphagia
Signs and symptoms
Heartburn (symptom) Pain or burning sensation in the esophagus,
can radiate to arms, jaw or back
Signs and symptoms
Abdominal pain Inflammatory - due to inflammation Mechanical - stretching of the walls of GI
tract Ischemic - due to buildup of metabolites
that are released in an area of reduced blood flow
Signs and symptoms
GI Bleeding Accumulation of blood in GI tract is irritating
and tends to cause discomfort; vomiting (Coffee ground vomit), diarrhea (black, tarry), or hematochezia (bleeding from rectum)
Signs and symptoms
Fecal incontinence Inability to control bowel movements Psychological factors - confusion, anxiety,
disorientation Physiologic - neurological / motor
impairment
Signs and symptoms
Changes begin before 50 y/o Oral changes (tooth decay) may lead to
difficulty with digestion Sensory changes - decreased taste buds
which can contribute to depressed appetite Salivary secretions decrease - dry mouth,
difficulty with digestion Organs lose tone but manage to function
well enough
Aging and the Gastrointestinal System
Net effect of changes includes decreased alimentary mobility (increased constipation),decreased blood flow, decreased nutrient absorption> slower digestion and emptying
There is a decline in “Intrinsic Factor” (IF) that typically promotes vitamin B12 absorptionin the stomach; this frequently occurs after middle age. In advanced age (90 y/o), prevalenceof problems associated with B12 deficiency is as high as 90% (anemia, neurological symptoms, constipation, weight loss)
Aging and Changes…
Hiatal Hernia
Definition & Incidence: lower esophageal sphincter gets enlarged and stomach passes through the diaphragm into the thoracic cavity
Estimated incidence of 5/1000 people / year Prevalence estimated at 60% of people over 60 y/o
(symptomatic and asymptomatic) Etiologic / risk factors - anything that weakens the diaphragm
muscle or alters the hiatus Pathogenesis / Clinical Manifestations: heart burn - worse when
lying down or with increased abdominal pressure Medical Management: diagnosed by ultrasound imaging or
barium swallow with fluoroscopy; treatment includes symptomatic control
ESOPHAGUS
Gastroesophageal Reflux Disease (esophagitis)
(GERD) Definition & Incidence: inflammation of
esophagus; increasing incidence with aging; 15% or more of the population may have
symptoms daily Types: reflux, chemical, infectious Etiologic / risk factors: backward flow of
stomach acids; irritation by nasogastric intubation or radiation
ESOPHAGUS
GERD (continued) Pathogenesis / Clinical Manifestations: Heart
burn, belching, dysphagia; problem is that long term GERD can result in Barrett’s
esophagus (metaplasia - dysplasia) which increases risk for neoplasia
ESOPHAGUS
GERD (continued) Medical Management: diagnosis with history,
endoscopy, barium radiography, H-pylori, esophageal pH Can be confused with angina; Nitroglycerin can help
determine cardiac vs. GERD pain (but not without error - some GERD goes away with nitroglycerin)
Treatment includes acid suppression, lifestyle modifications - drinking fluids between
meals but not with meals, loose fitting clothes, avoiding caffeine, nicotine, alcohol, aspirin,NSAIDs, remaining upright for at least 3 hours after meals, weight loss if obese
Minimally invasive surgery is being developed
ESOPHAGUS
Mallory-Weiss Syndrome Mucosal laceration of the lower end of
esophagus accompanied by bleeding. It is commonly caused by retching and
vomiting due to alcohol abuse, eating disorders or a viral syndrome
Diagnosis is made with endoscopy Treatment with fluid replacement, blood
transfusion Endoscopic ligation may be required
ESOPHAGUS
Neoplasm Definition & Incidence Two types - squamous cell and
adenocarcinoma Adenocarcinoma is relatively uncommon but
incidence is rising (H-pylori treatment might be reason)
Etiologic / risk factors: irritation, any change in function that keeps food in the esophagus
longer than it should that results in ulceration and metaplasia
ESOPHAGUS
Neoplasm (continued) Clinical Manifestations - dysphagia is the
primary sign / symptom, but it does not present until the esophagus is blocked between 30-50%; the only pain tends to be heartburn with lying down
ESOPHAGUS
Neoplasm (continued) Medical Management - prevention by treatment of
irritation / GERD, etc.; diagnosis with endoscopy Neoplasms are classified as resectable with
curative intent, resectable but notcurable, and not resectable/not curable; (depends on metastases, lymph node involvement)
Prognosis is poor - 5 year survival is 10%, with a median survival of less than 10 months(related to the lack of symptoms / signs until relatively late in the process)
ESOPHAGUS
Esophageal Varices Dilated veins in the lower third of esophagus
immediately beneath the mucosa due toportal hypertension usually associated with cirrhosis of the liver; usually painless butsignificant bleeding that can result in anemia and other low blood volume problems (inextreme cases shock)
About 1/2 cease without intervention; ligation may be needed; in extreme cases a stentmay be required to relieve portal hypertension
ESOPHAGUS
Congenital Conditions Tracheoesophageal Fistula TEF - most
common congenital esophageal anomaly; about 1 in 4000 live births; esophagus fails to make connection to the stomach : might go to trachea and then stomach; or trachea alone; or just end blindly with or without trachea making a connection to stomach - requires surgical repair
ESOPHAGUS
WHAT does this condition cause??
Depends on type See page 840 in Goodman
ESOPHAGUS
Tracheoesophageal FistulaNote: 90-95% of cases are type C
Gastritis Definition & Incidence - inflammation of the lining of
the stomach; represents a group of the most common stomach disorders; can be acute or chronic; most common form of chronic gastritis is caused by a bacterial infection: H-pylori
Etiologic / risk factors: serious illness, medication use (ASA, NSAID), stress, H-pylori
Clinical Manifestations - epigastric pain; can lead to GI bleeding
Medical Management - Dx by history, endoscopy, biopsy, tests of stool or blood for H-pylori;
Rx, remove cause if possible, time to heal
STOMACH
Peptic Ulcer Disease PUD
Definition & Incidence - break in protective mucosal lining which exposes submucosal areas to gastric contents/secretions
Two types – gastric (stomach) or duodenal (DUs are 2-3 x more prevalent)
Etiologic / risk factors: anything that causes gastritis Clinical Manifestations: epigastric pain - with burning, gnawing,
cramping, aching near xiphoid coming in waves; can include nausea, loss of appetite and weight loss.
Perforation causes increased pain in thoracic spine area T6-T11 with radiation to RUQ
Medical Management: Dx: same as gastritis; Rx - same as gastritis; surgical intervention is required for perforation
STOMACH
Gastric Cancer 1. Primary gastric lymphoma (relatively uncommon) 2. Gastric Adenocarcinoma - malignant neoplasm
originating from gastric mucosa Etiologic / risk factors - chronic gastritis Clinical Manifestations - - depends on variety of factors
such as size of tumor, presence of gastric outlet obstruction, metastatic versus nonmetastatic disease
Medical Management - Dx is usually delayed due to symptomatic treatment of gastritis (early stages may be asymptomatic)
Surgery is treatment of choice; prognosis depends on stage when discovered
STOMACH
Gastric cancer (continued) Prevention: presently best advice is to eat
at least 5 (1/2) cup servings of fruit and vegetables/daily combined with exercise, maintenance of healthy weight and reduced intake of salt-preserved foods
STOMACH
Congenital Conditions Pyloric Stenosis (PS) - obstruction of pyloric
sphincter (stomach into duodenum) Clinical Manifestations - projectile vomiting is the
most common and dramatic early sign - and may occur at birth
Projectile vomiting requires vomit to eject 1 foot or more when supine, or 3-4 feet when upright
Medical Management - antispasmodic medications (if effective) for 6-8 months to see ifstenosis loosens up; if it does not loosen up surgical repair is required
STOMACH
Malabsorption Syndrome Definition & Incidence - group of disorders
(celiac disease, cystic fibrosis, Crohn’sdisease, chronic pancreatitis, pancreatic carcinoma, pernicious anemia, short gut syndrome, fibrotic changes due to gastroenteritis) characterized by reduced intestinal absorptionof dietary components and excessive loss of nutrients in the stool
INTESTINES
Malabsorption syndrome (continued) Traditionally classified as: Maldigestion- failure of chemical process of
digestion Malabsorption- failure of intestinal mucosa
to absorb nutrients
Can occur separately or together simultaneously
INTESTINES
Malabsorption syndrome (continued) Etiologic / risk factors - most often in
therapy will see patients with gastroenteritis due to NSAID use and resultant fibrotic changes leading to malabsorption
INTESTINES
Malabsorption syndrome (continued) Clinical Manifestations - Progressive - related to
nutrient deficiency General malaise - weakness, fatigue, muscle wasting B12 - pernicious anemia Iron, vit A, D, K - osteomalacia Calcium, vit D, magnessium - tetany Vit B complex - Numbness and tingling Electrolytes - muscle spasms, palpitations Vit K - easy bruising / bleeding Protein - generalized swelling
INTESTINES
Malabsorption syndrome (continued) Medical Management - treat underlying
condition; nutritional supplementation – may need to bypass GI (parenteral nutrition - IV feeding); prognosis depends on underlyingcondition
INTESTINES
Vascular Diseases Embolic occlusions of visceral branches
of abdominal aorta Intestinal Ischemia - caused by
atherosclerosis or emboli; pain, rapid onset of cramping
Rx - surgery
INTESTINES
Bacterial Infections Food borne illnesses such as botulism are
caused by bacteria. Can be fatal. Appropriate treatment depends on identifying pathogen. Many episodes of acute gastroenteritis need fluid replacement and supportive care.
INTESTINES
Inflammatory Bowel Disease (IBD) Definition & Incidence - 1. Crohn’s disease (CD) - chronic, life long
inflammatory disorder that can affect any segment of the intestinal tract with “skips” (sections of normal bowel with skips or lesions)
2. Ulcerative colitis (UC) - chronic inflammatory disorder of the mucosa of the colon in a continuous manner –chronic diarrhea and rectal bleeding
INTESTINES
IBD (continued) Etiologic / risk factors - both have unknown etiologies Pathogenesis - both are considered autoimmune Clinical Manifestations - recurrent involvement of
intestinal segments resulting in a chronic, unpredictable course
Inflammatory process begins with low-grade fever, malaise, weight loss, diarrhea and abdominal cramping / pain; may be followed by obstructive phase with persistent bloating
and distention from the movement of gas through the system
INTESTINES
IBD (continued) Medical Management - Dx only by history
and ruling out other conditions; monitoring includes use of radiographs, colonoscopy, barium enema x-ray, fecal occult blood tests, blood testing
Rx: symptom relief, anti inflammatory meds, diet, surgery to resect parts of intestine may be necessary
INTESTINES
Antibiotic Associated Colitis
Antibiotics can disrupt normal GI bacterial flora; common for C - difficile (Clostridium difficile) to dominate; it is a microorganism that can replace normal GI tract flora
It is not invasive, but can create toxins that damage the colonic mucosa; signs start as alot of watery diarrhea - can occur early with antibiotic treatment or within 4 weeks after the medications have stopped.
Treatment is aimed at fluid and nutrition replacement, and antimicrobials can be prescribed to treat the c-diff
INTESTINES
Irritable Bowel Syndrome (IBS) Definition & Incidence - group of symptoms
- most common disorder of the GI system - Referred to as ‘nervous indigestion’, ‘spastic
colon’, ‘nervous colon’ and ‘irritable colon’ There is absence of inflammation; it should
not be confused with Crohn’s or Ulcerative colitis
(It is not as severe - there are no structural or biochemical defects identified)
INTESTINES
IBS (continued) Etiologic / risk factors - three main
functional abnormalities: 1. altered GI motor activity;
2. visceral hypersensitivity; 3. altered processing of information by the nervous system
INTESTINES
IBS (continued) Clinical Manifestations - Abdominal pain that is
relieved by a bowel movement, bloating,distention, passage of mucus, changes in stool form (hard or loose and watery),alterations in stool frequency, or difficulty in passing a movement
Medical Management - Dx - history; no test. Rx aimed at symptoms, lifestyle changes
(dietary), stress reduction, behavior therapy (to identify and reduce triggers)
INTESTINES
Diverticular Disease Diverticulosis - outpouchings in intestinal wall,
uncomplicated Diverticulitis - inflammed outpouching,
complicated Asymptomatic in 80% of people with
diverticulosis; when inflammed - severe pain Treatment to relieve symptoms, prevent
diverticulitis; if diverticulitis may need antibiotics and complete rest of colon with naso gastric tube feedings and IV fluids until inflammatory process has been resolved
INTESTINES
Diverticular disease (clarified) *outpouching is called diverticula The presence of diverticula in wall of colon
or small intestine describes the herniation of mucosa through the muscles of the colon
It is when food particles or feces become trapped in diverticula and become infected and inflammed >>> diverticulitis
Rarely reversible
INTESTINES
Neoplasms Intestinal Polyps - growth or mass in wall of intestines
Benign Tumors (most common adenomas, leiomyomas, lipomas) - Rarely become malignant; only need to be treated if causing symptoms
Malignant Tumors Adenocarcinoma - (colorectal cancer) second leading cause
of cancer death in US men and women combined; they have a long pre-invasive phase; few early warning signs - rely on medical screening with colonoscopy; persistent change in bowel habits is the single most consistent symptom
Rx: surgical removal
INTESTINES
Obstructive Disease
Definition & Incidence - anything that reduces the size of the gastric outlet, preventing normal flow of chyme and delaying gastric emptying
Leads to: distention, cramping pain, tenderness that progresses to point of being constant, vomiting due to reflux, constipation, signs of dehydration, hypovolemia
After ~ 24 hours of complete obstruction, impaired blood supply can lead to necrosis and strangulation; can cause fever, leukocytosis, peritoneal signs or blood in feces
INTESTINES
Obstructive Disease (continued) Three causes: Organic, mechanical,
functional
1. Organic: due to another condition
INTESTINES
2. Mechanical Obstruction Adhesion - scar tissue from surgeries Intussusception - telescoping of intestines
on itself (Figure 16-17) Volvulus - twisting Hernia - protrusion of intestines through the
groin, abdomen, navel (weakness in muscle and connective tissue normally containing it)
INTESTINES
Mechanical Obstructions of Intestines
3. Functional Obstruction Adynamic or Paralytic Ileus - neurologic or
muscular impairment of peristalsis Oglvie’s Syndrome - Acute colonic pseudo-
obstruction early postoperativelyfollowing trauma to hip, pelvis, or after elective hip or pelvic surgery; etiologyunknown - but thought to be related to disruption to sacral parasympathetic nerves (S2-S4 supply colon and rectum)
INTESTINES
Congenital Conditions Stenosis & Atresia - stenosis - narrowing of
small intestine; atresia is a defectcaused by incomplete formation of lumen
Meckels Diverticulum - outpouching of the bowel located at the ileum of smallintestine
INTESTINES
Definition & Incidence - inflammation of the vermiform appendix that often results in necrosis and perforation and subsequent peritonitis
Etiologic / risk factors - 1/2 no known cause; 1/3 due to obstruction of some type that prevents drainage (what is the other 1/6 is caused by?)
Pathogenesis - obstruction -> infection; or just infection Clinical Manifestations - constant pain RLQ, n&v ;
children - fever; adults - mild fever; aggravated by anything that increase abdominal pressure Can present atypically “Pinch an inch” test > rebound test Medical Management - remove appendix
APPENDIX- appendicitis
Peritonitis
Definition & Incidence - inflammation of peritonium –serous membrane lining the wall of abdominal cavity; ifspontaneous >primary; if due to trauma, surgery, peritoneal contamination from a perforation > secondary.
Etiologic / risk factors - primary ?; secondary, trauma, surgery, GI issue that leads to perforation
Clinical Manifestations - decreased GI motility and distention with gas; vague generalized abdominal pain; as progresses becomes severe pain and abdomen becomes rigid (involuntary guarding), n&v, fever
Medical Management - infection control, and treat consequences
PERITONEUM
Rectal (or anal) Fissure Ulceration or tear of lining of the anal canal
- usually caused by excessive tissue stretchingor tearing such as during childbirth or a large, hard bowel movement; tends to re-open frequently
Heal within a month or two - may need stool softeners to help facilitate healing by preventing re injury
RECTUM AND ANUS
Rectal Abscesses and Fistulas Abscesses (infection) or fistula (opening)
can occur as a result of an infected anal gland,fissure or prolapsed hemorrhoid and are most common in people with Crohn’s disease
RECTUM
Hemorrhoids “piles”
Varicose veins of a pillow like cluster of veins that lie just beneath the mucus membraneat the lowest part of the rectum - associated with anything that increases intra-abdominalpressure (Box 16-1); internal hemorrhoids may require ligation (tying up), sclerosing (shrinking the vessels) , laser or cryosurgery to destroy the tissue; external can be treated with local applications of topical medications, high fiber diet, avoidance of constipation
RECTUM and/or ANUS
1. The Digestive System
Diagram, Organs, Function, and More - WebMDwww.webmd.com/digestive-disorders/digestive-system
2. Upper GI Tract Anatomy - eMedicine World Medical Libraryemedicine.medscape.com/article/1899389-overview
3. Gut. 2004 February; 53(2): 310–311. 4. Evolution Of The Human Appendix: A Biological 'Remna
nt' No Morewww.sciencedaily.com/releases/2009/08/090820175901.htm
5. Achalasia — Diagnosis and treatment at Mayo Clinicwww.mayoclinic.org/achalasia/
Resources/references
Emotional Support Animals
Emotional Support AnimalsAndrea C. Mendes PT, DPT
Sean M. Collins PT, ScD