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