Chapter 15Chapter 15The Gastrointestinal System:The Gastrointestinal System:

Fuel for the TripFuel for the Trip““You are what you eatYou are what you eat!!!”!!!”

oink----oinkoink----oink!!!!!!

IntroductionIntroduction

Gastrointestinal System Functions:Gastrointestinal System Functions: IngestIngest raw materials raw materials Physically Physically & & chemically digestchemically digest raw material to raw material to

usable elements.usable elements. AbsorbAbsorb elements elements EliminateEliminate what is what is NOTNOT useable useable

System FunctionsSystem Functions

IngestionIngestion: food enters mouth: food enters mouth MasticationMastication: chewing: chewing DigestionDigestion: : chemical actchemical act of breaking down food into of breaking down food into

small molecules.small molecules. SecretionSecretion: acids, buffers, enzymes, & H2O aid in : acids, buffers, enzymes, & H2O aid in

breakdown of food.breakdown of food. AbsorptionAbsorption: molecules pass through lining of : molecules pass through lining of

digestive tract.digestive tract. Excretion or defecationExcretion or defecation: elimination of waste : elimination of waste

products.products.

The Digestive SystemThe Digestive System

BuccalBuccal ( (oraloral) ) CavityCavity

LipsLips: act as door to cavity: act as door to cavity Hard Hard & & Soft PalateSoft Palate: form : form roofroof of mouth of mouth TongueTongue: acts as : acts as floorfloor CheeksCheeks: form : form wallswalls

TongueTongue

MuscleMuscle: provides : provides taste taste stimuli to stimuli to brain, determines brain, determines temperaturetemperature, , manipulatesmanipulates food, & aids in food, & aids in swallowingswallowing..

SalivaSaliva: added to moisten & soften : added to moisten & soften food, while teeth crush food.food, while teeth crush food.

BolusBolus: : ball-like massball-like mass, pushed by , pushed by tongue so it may be swallowed, tongue so it may be swallowed, passed to passed to pharynxpharynx..

Lingual FrenulumLingual Frenulum: : membrane under membrane under tonguetongue, keeps you from swallowing , keeps you from swallowing tongue & aids in speaking.tongue & aids in speaking.

Buccal & Oral PharynxBuccal & Oral Pharynx

Salivary GlandsSalivary Glands SublingualSublingual: found under tongue: found under tongue SubmandibularSubmandibular: located along both sides of inner : located along both sides of inner

surface of mandible, or lower jaw.surface of mandible, or lower jaw. Controlled byControlled by: autonomic nervous system: autonomic nervous system ParotidParotid: slightly inferior & anterior to each ear. : slightly inferior & anterior to each ear.

Swell with “Swell with “viral Parotitisviral Parotitis..”..”

Salivary GlandsSalivary Glands con’t con’t

ProducesProduces: : 1–1.5 liters1–1.5 liters of saliva QD of saliva QD Keep mouth moistKeep mouth moist: but idea or presence of food : but idea or presence of food

increase production significantly.increase production significantly. ContainsContains: : 99.4%99.4% water, & contains antibodies, water, & contains antibodies,

buffers, ions, waste products, & enzymes.buffers, ions, waste products, & enzymes.

Salivary GlandsSalivary Glands con’t con’t

EnzymesEnzymes: act as : act as organic catalystsorganic catalysts to to speed upspeed up chemical reactions.chemical reactions.

Salivary AmylaseSalivary Amylase: speeds chemical activity of : speeds chemical activity of breaking down breaking down carbohydratescarbohydrates..

Saliva cleans oral surfacesSaliva cleans oral surfaces, reducing amount of , reducing amount of bacteriabacteria that grows in mouth. that grows in mouth.

TeethTeeth

DeciduousDeciduous: first set of teeth as a : first set of teeth as a babybaby First toothFirst tooth: appears : appears @ 6 months@ 6 months of age; lower of age; lower

central incisors appear first, all central incisors appear first, all 20 teeth20 teeth in place by in place by age age 2½.2½.

Between 6 and 12 yearsBetween 6 and 12 years these teeth fall out, are these teeth fall out, are replaced by replaced by 32 permanent teeth32 permanent teeth..

Wisdom teethWisdom teeth: appear by age : appear by age 2121

TeethTeeth Con’t Con’t

IncisorsIncisors: at front of mouth, blade shaped, used to : at front of mouth, blade shaped, used to cut cut foodfood..

CanineCanine: for holding, tearing, or slashing food; known : for holding, tearing, or slashing food; known as as eyeteetheyeteeth or or cuspidscuspids, located next to incisors., located next to incisors.

BicuspidsBicuspids: or premolars: transitional teeth: or premolars: transitional teeth MolarsMolars: have : have flattened topsflattened tops; both bicuspids & molars ; both bicuspids & molars

are responsible for are responsible for crushingcrushing & & grindinggrinding food. food.

TeethTeeth Con’t Con’t

Parts of ToothParts of Tooth:: CrownCrown: covered by hard : covered by hard

enamel.enamel. NeckNeck: transitional section that : transitional section that

leads to root.leads to root. RootRoot: nestled in bony socket, : nestled in bony socket,

held in place by fibers of held in place by fibers of periodontal ligamentperiodontal ligament..

DentinDentin: made of : made of mineralizedmineralized bone-like substance.bone-like substance.

Teeth Con’tTeeth Con’t

Connective tissueConnective tissue: pulp, : pulp, located in located in pulp cavitypulp cavity

Pulp cavityPulp cavity: contains blood : contains blood vesselsvessels & & nervesnerves providing providing nutrients & sensation; nerves nutrients & sensation; nerves & blood vessels get to pulp & blood vessels get to pulp cavity via cavity via root canalroot canal..

CementumCementum: (soft version of : (soft version of bone) covers dentin of root, bone) covers dentin of root, aiding in securing aiding in securing periodontal periodontal ligamentligament..

TeethTeeth Con’t Con’t

GingivaGingiva: gums, help hold teeth in place: gums, help hold teeth in place Epitheal cellsEpitheal cells form tight seal around tooth to form tight seal around tooth to

prevent bacteria from coming into contact with prevent bacteria from coming into contact with tooth’s tooth’s cementumcementum..

Pathology ConnectionPathology Connection: : Oral DisordersOral Disorders

Dental CariesDental Caries (cavities) (cavities) Form whenForm when microorganismsmicroorganisms attack attack

tooth enameltooth enamel Related to dental plaqueRelated to dental plaque: sticks to : sticks to

teeth forming sticky substance.teeth forming sticky substance. Forms great hideoutForms great hideout for for bacteriabacteria Bacteria createsBacteria creates acidsacids that attack that attack

surface of teeth.surface of teeth.

Risk Factors for Plaque FormationRisk Factors for Plaque Formation

HighHigh carbohydrate diet carbohydrate diet PoorPoor dental hygiene dental hygiene Lack of Lack of regular visits to dentist regular visits to dentist

Risk Factors for Plaque Formation Risk Factors for Plaque Formation con’tcon’t

RXRX: : Clear out & fill cariesClear out & fill caries Rx infectionRx infection

PreventionPrevention:: Proper dental careProper dental care Fluoride in H2O & tooth pasteFluoride in H2O & tooth paste Evaluate for Evaluate for heart diseaseheart disease & & buccal cabuccal ca

Pathology ConnectionPathology Connection::Periodontal DiseasePeriodontal Disease

Plaque & bacteriaPlaque & bacteria affects gums & affects gums & supportivesupportive structures of teeth.structures of teeth.

Can result inCan result in gingivitisgingivitis, , bleedingbleeding & tooth loss & tooth loss

Pathology Connection:Pathology Connection:Oral & Lip CancerOral & Lip Cancer

CauseCause:: Excessive sun exposureExcessive sun exposure Tobacco Tobacco ETOHETOH

Oral & Lip Cancer Oral & Lip Cancer con’tcon’t

Leukoplakia:Leukoplakia: white patch of tissue in mouthwhite patch of tissue in mouth associated with use of chewing tobaccoassociated with use of chewing tobacco

Pathology ConnectionPathology Connection::StomatitisStomatitis

Inflammation of oral mucosaInflammation of oral mucosa poor fitting denturespoor fitting dentures Apthous stomatitisApthous stomatitis (“ (“canker sorescanker sores”)”) CheilitisCheilitis: cracking & inflammation of lips & corners : cracking & inflammation of lips & corners

of mouth; often related to infection, allergy, or of mouth; often related to infection, allergy, or nutritional deficiency.nutritional deficiency.

Pharynx Pharynx (3 Parts)(3 Parts)

NasopharynxNasopharynx:: primarily partprimarily part of respiratory system, of respiratory system,

blocked by soft palate.blocked by soft palate.

Oropharynx & laryngopharynxOropharynx & laryngopharynx:: act as passageway for food, water, & act as passageway for food, water, &

airair; ; epiglottisepiglottis covers trachea to covers trachea to prevent food from entering lungs, prevent food from entering lungs, forcing food into opening for forcing food into opening for esophagus.esophagus.

EsophagusEsophagus

10 inches long10 inches long, is connected to stomach, is connected to stomach from pharynx, through thoracic cavity, through from pharynx, through thoracic cavity, through

diaphragm, connecting to stomach in peritoneal diaphragm, connecting to stomach in peritoneal cavity.cavity.

normally normally collapsed tubecollapsed tube until “ until “bolusbolus” of food ” of food swallowed.swallowed.

PeristalsisPeristalsis: pushes food down esophagus: pushes food down esophagus

Esophagus Esophagus con’tcon’t

lined withlined with stratified squamous epitheliumstratified squamous epithelium that that secrete secrete mucusmucus to make walls slippery; cells make to make walls slippery; cells make lining.lining.

resistant toresistant to abrasion, temperature extremes, & abrasion, temperature extremes, & irritation.irritation.

Pharyngoesophageal sphincter: relaxes to open Pharyngoesophageal sphincter: relaxes to open esophagus so food can enter.esophagus so food can enter.

Esophagus Esophagus con’tcon’t

Lower Esophageal SphincterLower Esophageal Sphincter: : opening door to stomach & opening door to stomach & closing to prevent acidic gastric closing to prevent acidic gastric juices from splashing into juices from splashing into esophagus causing esophagus causing heartburnheartburn..

process of swallowingprocess of swallowing: : foodfood 9 9 secondsseconds; ; fluidfluid take take only secondsonly seconds to reach stomach.to reach stomach.

Walls of the Alimentary CanalWalls of the Alimentary Canal

StomachStomach LocatedLocated: ULQ under : ULQ under

diaphragm, posterior to diaphragm, posterior to Liver.Liver.

10 inches long10 inches long with with diameter dependent on diameter dependent on how much just eaten.how much just eaten.

4 liters4 liters when filled when filled RugaeRugae: folds, help : folds, help

stomach expand and stomach expand and contract.contract.

4 Function of Stomach4 Function of Stomach

HoldingHolding area area for received foodfor received food Chemical digestionChemical digestion: gastric acids & enzymes mix : gastric acids & enzymes mix

with food.with food. Regulates rateRegulates rate of of ChymeChyme movement into small movement into small

intestines. intestines. AbsorbsAbsorbs small amounts of small amounts of H2OH2O & & ETOHETOH

How Fast Stomach EmptiesHow Fast Stomach Empties

4 hours4 hours to empty following meal to empty following meal LiquidsLiquids & & carbohydratescarbohydrates pass quickly pass quickly ProteinsProteins take longer take longer FatsFats take longest 4-6 hours take longest 4-6 hours

4 Regions of Stomach4 Regions of Stomach

Cardiac RegionCardiac Region: surrounding lower : surrounding lower esophageal sphincter.esophageal sphincter.

FundusFundus: laterally & slightly superior : laterally & slightly superior to cardiac region. Temporarily holds to cardiac region. Temporarily holds food as it enters stomach.food as it enters stomach.

BodyBody: Mid-portion: Mid-portion PylorusPylorus: :

1. terminal end of stomach 1. terminal end of stomach

2. most of work 2. most of work performedperformed

3. where food passes through 3. where food passes through pyloric sphincterpyloric sphincter into small intestine. into small intestine.

Chemical DigestionChemical Digestion

Gastric Juice: Gastric Juice: 1500 mls produced QD1500 mls produced QD hydrochloric acid (HCl)hydrochloric acid (HCl) pepsinogenpepsinogen mucus mucus

PepsinogenPepsinogen, , HCL HCL && Pepsin Enzymes Pepsin Enzymes

chief chief digestive enzymedigestive enzyme secreted bysecreted by chief cellschief cells HCL HCL secreted by secreted by parietal cellsparietal cells combining to combining to

produce produce pepsinpepsin.. PepsinPepsin breaks down breaks down proteinprotein HClHCl breaks down breaks down connective tissueconnective tissue

Stomach & Enzymes Stomach & Enzymes con’tcon’t

HCLHCL: pH of : pH of 1.5–2.01.5–2.0, effective at killing pathogens., effective at killing pathogens. Mucous cellsMucous cells: generate thick layer of mucus : generate thick layer of mucus

shielding stomach from effects of stomach acids.shielding stomach from effects of stomach acids. Stomach secretesStomach secretes intrinsic factor, allowing intrinsic factor, allowing

vitamin Bvitamin B1212 to be absorbed. to be absorbed.

Enzyme activity controlledEnzyme activity controlled by by parasympatheticparasympathetic nervous system (nervous system (vagus nervevagus nerve))

Vagus increases motilityVagus increases motility & secretory rates of & secretory rates of gastric glands.gastric glands.

Gastric Glands & Their Functions

3 Phases of Gastric Juice Production3 Phases of Gastric Juice Production

I. Cephalic PhaseI. Cephalic Phase:: sensory stimulationsensory stimulation (sight (sight

or smell of food) or smell of food) stimulatesstimulates parasympathetic parasympathetic

nerves via medulla nerves via medulla oblongataoblongata

GastrinGastrin released released stimulatingstimulating gastric gland gastric gland

activity in stomachactivity in stomach

3 Phases of Gastric Juice Production 3 Phases of Gastric Juice Production con’tcon’t

II. Gastric PhaseII. Gastric Phase:: 2/3 of gastric juices2/3 of gastric juices secreted as food enters secreted as food enters

stomach & distends walls.stomach & distends walls. signaling stomachsignaling stomach to secrete more gastric fluid to secrete more gastric fluid

3 Phases of Gastric Juice Production 3 Phases of Gastric Juice Production con’tcon’t

III. Intestinal PhaseIII. Intestinal Phase:: food enters duodenumfood enters duodenum, distending & sensing , distending & sensing

acidity.acidity. intestinal hormones intestinal hormones releasedreleased slowingslowing gastric gland secretions gastric gland secretions lasts until lasts until bolusbolus leaves leaves duodenumduodenum

3 Phases of Gastric Juice Production 3 Phases of Gastric Juice Production con’tcon’t

Rate of Movement of ChymeRate of Movement of Chyme

If too slowIf too slow:: rate of nutrient digestion & absorption rate of nutrient digestion & absorption decreaseddecreased may allow may allow acidity of chymeacidity of chyme to cause erosions of to cause erosions of

stomach lining (stomach lining (ulcersulcers).).

If too quickIf too quick:: food particles may not be sufficiently mixed with food particles may not be sufficiently mixed with

gastric juices.gastric juices. insufficient digestion; insufficient digestion; chymechyme not given time to not given time to

neutralize can cause erosion of neutralize can cause erosion of intestinal lining intestinal lining ((ulcersulcers).).

Pathology Connection: Pathology Connection: Stomach Acid DisordersStomach Acid Disorders

Gastroesophageal Reflux Disease (GERD)Gastroesophageal Reflux Disease (GERD) Condition where acidic stomach contents Condition where acidic stomach contents

“squirt” back into esophagus “squirt” back into esophagus Since esophagus does not have protective Since esophagus does not have protective

mucus, can cause inflammation and ulceration mucus, can cause inflammation and ulceration of esophageal tissueof esophageal tissue

Scar tissue can eventually form, causing Scar tissue can eventually form, causing narrowing of esophagusnarrowing of esophagus

If left untreated, constant inflammation can lead If left untreated, constant inflammation can lead to esophageal cancerto esophageal cancer

GERD cont.GERD cont. s/ss/s epigastric pain and burning, can be worse epigastric pain and burning, can be worse

when lying downwhen lying down d/x d/x symptoms, upper GIsymptoms, upper GI R/xR/x

• Antacids: treat burning sensation by decreasing acidAntacids: treat burning sensation by decreasing acid• Acid reducing medsAcid reducing meds• Lifestyle changes: may help prevent GERDLifestyle changes: may help prevent GERD

Limiting fats, alcohol, caffeine and chocolate in dietLimiting fats, alcohol, caffeine and chocolate in diet Avoiding smokingAvoiding smoking Avoiding lying down in 4 hours after eatingAvoiding lying down in 4 hours after eating Sleeping with head of bed elevatedSleeping with head of bed elevated If obese, weight lossIf obese, weight loss

Peptic UlcersPeptic Ulcers

Etiology: Breakdown of mucosal membrane in esophagus, stomach, or small Etiology: Breakdown of mucosal membrane in esophagus, stomach, or small intestine; develop most commonly in duodenumintestine; develop most commonly in duodenum

Factors that increase risk:Factors that increase risk:• Helicobacter pylori (H. pylori) infection in stomach:Helicobacter pylori (H. pylori) infection in stomach:• SmokingSmoking• Heavy/chronic alcohol consumptionHeavy/chronic alcohol consumption• Use of NSAID medications (including aspirin and others)Use of NSAID medications (including aspirin and others)• Caffeine consumptionCaffeine consumption

Peptic Ulcer cont.Peptic Ulcer cont.

• Use of corticosteroid medicationsUse of corticosteroid medications• Stress Stress

Small IntestineSmall Intestine

major organ of major organ of digestion, is where digestion, is where most of food digestedmost of food digested

average length of 6–average length of 6–20 feet and diameter 20 feet and diameter ranging from 2.5-4 cmranging from 2.5-4 cm

Walls secrete Walls secrete digestive enzymes digestive enzymes and hormones to and hormones to stimulate pancreasstimulate pancreas

Small Intestine cont.Small Intestine cont.

80% of absorption of usable nutrients 80% of absorption of usable nutrients occurs in sm. Intestineoccurs in sm. Intestine

Remaining 20% absorbed in stomachRemaining 20% absorbed in stomach Any residue not utilized in small intestine Any residue not utilized in small intestine

sent to large intestine for removal from sent to large intestine for removal from bodybody

Sections of sm. intestineSections of sm. intestine

Three regions Three regions Duodenum: Duodenum:

approximately 25 cm approximately 25 cm long (10 inches)long (10 inches)

Jejunum: middle Jejunum: middle section, approximately section, approximately 2.5 m long2.5 m long

Ileum: terminal end, 2 Ileum: terminal end, 2 meters long, attaches meters long, attaches to large intestine at to large intestine at ileocecal valveileocecal valve

Sm. Intestine cont.Sm. Intestine cont.

Pyloric valve allows small portions of Pyloric valve allows small portions of chyme to enter duodenumchyme to enter duodenum

Pancreas and gallbladder add secretions: Pancreas and gallbladder add secretions: bile from gallbladder, pancreatic juice with bile from gallbladder, pancreatic juice with enzymes from pancreasenzymes from pancreas

Bile emulsifies fat, making fat disperse in Bile emulsifies fat, making fat disperse in waterwater

Pancreatic juice contains sodium Pancreatic juice contains sodium bicarbonate which neutralizes acidic bicarbonate which neutralizes acidic chymechyme

Sm. Intestine Cont.Sm. Intestine Cont.

Wall has circular folds called plicae Wall has circular folds called plicae circulares and finger-like protrusions into circulares and finger-like protrusions into lumen called villilumen called villi

Villi also have microscopic extensions known as Villi also have microscopic extensions known as microvillimicrovilli

Purpose: to provide increase in surface area of Purpose: to provide increase in surface area of small intestine (almost to size of tennis court) small intestine (almost to size of tennis court) increasing efficiency of absorption of nutrientsincreasing efficiency of absorption of nutrients

VilliVilli

Large Large IntestineIntestine

Beginning at junction Beginning at junction of small intestine, of small intestine, ileocecal orifice, and ileocecal orifice, and extending to anusextending to anus

Borders small Borders small intestineintestine

No villi in large No villi in large intestine so little intestine so little nutrient absorption nutrient absorption occurs hereoccurs here

Functions of Large IntestineFunctions of Large Intestine

Water absorptionWater absorption

Absorption of vitamins produced by Absorption of vitamins produced by normal bacteria in large intestinenormal bacteria in large intestine

Packaging/compacting waste Packaging/compacting waste products for elimination from bodyproducts for elimination from body

Lg. Intestine cont.Lg. Intestine cont.

5 feet long and 2.5 inches in diameter5 feet long and 2.5 inches in diameter

3 main regions: cecum, colon, and rectum3 main regions: cecum, colon, and rectum

cecum, receives any undigested food and cecum, receives any undigested food and water from ileumwater from ileum

Large Large IntestineIntestine

*Four sections of *Four sections of colon: ascending, colon: ascending, transverse, transverse, descending, and descending, and sigmoidsigmoid

*Ascending colon *Ascending colon travels up right sidetravels up right side

*Transverse colon *Transverse colon travels across travels across abdomen just below abdomen just below liver and stomachliver and stomach

*Descending colon *Descending colon travels to left side travels to left side

Lg. Intestine cont.Lg. Intestine cont.

Sigmoid colon extends to rectumSigmoid colon extends to rectum

Rectum opens to anal canal that leads to Rectum opens to anal canal that leads to anusanus

Anal sphincter opens and closes to allow Anal sphincter opens and closes to allow passage of solid waste (feces)passage of solid waste (feces)

Role of Intestinal BacteriaRole of Intestinal Bacteria

Help break down indigestible materialsHelp break down indigestible materials

Produce B complex vitamins and most of vitamin Produce B complex vitamins and most of vitamin K needed for proper blood clottingK needed for proper blood clotting

Pathology: Lg. IntestinePathology: Lg. Intestine

Hemorrhoids Hemorrhoids Etiology: varicose veins in rectumEtiology: varicose veins in rectum S/SS/S: pain, itching/burning sensation, bleeding: pain, itching/burning sensation, bleeding DxDx: proctoscopy, stool sample examination: proctoscopy, stool sample examination TxTx: dietary changes (more fiber/water), stool : dietary changes (more fiber/water), stool

softeners, medication to relieve discomfortsofteners, medication to relieve discomfort

Colorectal CancerColorectal Cancer

Risk factors include: Risk factors include: • Genetic predispositionGenetic predisposition• Diet rich in animal fatDiet rich in animal fat• Diet lacking appropriate amounts of fiber and Diet lacking appropriate amounts of fiber and

calciumcalcium• Tobacco usage and excessive alcohol Tobacco usage and excessive alcohol

consumptionconsumption• Higher than normal levels of “bad” cholesterol in Higher than normal levels of “bad” cholesterol in

serumserum• Sedentary lifestyleSedentary lifestyle

Colorectal Cancer cont.Colorectal Cancer cont.

S/S: rectal bleeding, possible abd. painS/S: rectal bleeding, possible abd. pain

Dx: colonoscopyDx: colonoscopy

Tx: surgical removal of tumor, chemo, Tx: surgical removal of tumor, chemo, radiation possible.radiation possible.

DiverticulitisDiverticulitis

Etiology: infection and inflammation of Etiology: infection and inflammation of diverticulum (sac in intestinal tract)diverticulum (sac in intestinal tract)

S/SS/S: bleeding, abd. pain, fever, hyperactive : bleeding, abd. pain, fever, hyperactive bowel soundsbowel sounds

DxDx: patient hx and exam, blood work, : patient hx and exam, blood work, colonoscopy, endoscopycolonoscopy, endoscopy

TxTx: high fiber diets, stool softeners, antibiotics, : high fiber diets, stool softeners, antibiotics, surgical interventionsurgical intervention

DiverticulitisDiverticulitis

Accessory Accessory OrgansOrgans

-Liver-Liver

-Gall Bladder-Gall Bladder

-Pancreas-Pancreas

LiverLiver

Weighs 1.5 kg, is largest glandular organ Weighs 1.5 kg, is largest glandular organ in bodyin body

Divided into large right lobe and smaller Divided into large right lobe and smaller left lobe; right lobe has two smaller inferior left lobe; right lobe has two smaller inferior lobelobe

Receives about 1½ quarts of blood every Receives about 1½ quarts of blood every minute from hepatic portal vein and minute from hepatic portal vein and hepatic artery hepatic artery

Functions of the LiverFunctions of the Liver

Detoxifies body of harmful substances such as Detoxifies body of harmful substances such as certain drugs and alcoholscertain drugs and alcohols

Creates body heat Creates body heat Destroys old blood cells Destroys old blood cells Eliminates the pigment bilirubin in bile which Eliminates the pigment bilirubin in bile which

gives feces its distinctive colorgives feces its distinctive color Forms blood plasma proteins, such as albumin Forms blood plasma proteins, such as albumin

and globulinand globulin

Functions of the Liver cont.Functions of the Liver cont.

Produces clotting factors fibrinogen and Produces clotting factors fibrinogen and prothrombinprothrombin

Creates anticoagulant heparin Creates anticoagulant heparin Manufactures bileManufactures bile Stores and modifies fats for more efficient Stores and modifies fats for more efficient

usage by body’s cellsusage by body’s cells Synthesizes urea, a by-product of protein Synthesizes urea, a by-product of protein

metabolismmetabolism

Functions of the Liver cont.Functions of the Liver cont.

Stores glucose, as glycogen; when Stores glucose, as glycogen; when blood sugar level falls below normal, blood sugar level falls below normal, liver reconverts glycogen to glucose and liver reconverts glycogen to glucose and releases it into the bloodreleases it into the blood

Stores ions, vitamins A, BStores ions, vitamins A, B1212, D, E, and K, D, E, and K

Makes cholesterolMakes cholesterol

Gall BladderGall Bladder

Sac-shaped organ, 3–4 inches long, Sac-shaped organ, 3–4 inches long, located under liver’s right lobelocated under liver’s right lobe

Stores bile and absorbs much of its water Stores bile and absorbs much of its water content, making it 6–10 times more content, making it 6–10 times more concentrated; if over-concentrated, bile concentrated; if over-concentrated, bile salts may solidify, forming gall stonessalts may solidify, forming gall stones

Fatty foods in duodenum cause release of Fatty foods in duodenum cause release of CCK which causes bile to release into the CCK which causes bile to release into the duodenum via common bile ductduodenum via common bile duct

Pathology Connection: Pathology Connection: Cholelithiasis and CholecystitisCholelithiasis and Cholecystitis

Etiology: inflammation of gallbladder; presence Etiology: inflammation of gallbladder; presence of stones or calculi in gallbladder or common of stones or calculi in gallbladder or common bile ductbile duct

Incidence increases with age, common in men, Incidence increases with age, common in men, women following multiple pregnancies, obese women following multiple pregnancies, obese patients, diabetics, and patients who have had patients, diabetics, and patients who have had rapid weight lossrapid weight loss

Cholelithiasis cont.Cholelithiasis cont.

S/SS/S: : • Asymptomatic/mild discomfort to extreme Asymptomatic/mild discomfort to extreme

pain often preceded with ingestion of fatty pain often preceded with ingestion of fatty or greasy foodsor greasy foods

• pain usually steady lasting from 15–30 pain usually steady lasting from 15–30 minutes or up to several hours with minutes or up to several hours with spontaneous resolutionspontaneous resolution

• nausea/vomiting, bloating, flatulence, nausea/vomiting, bloating, flatulence, abdominal tendernessabdominal tenderness

• Possible low grade feverPossible low grade fever

Cholelithiasis cont.Cholelithiasis cont.

DxDx: exam/pt hx, ultrasound, blood work with rise : exam/pt hx, ultrasound, blood work with rise in leukocyte count during acute cholecystitis in leukocyte count during acute cholecystitis (although other values usually within normal (although other values usually within normal range)range)

Tx: changes in diet, observation, surgical Tx: changes in diet, observation, surgical removal if deemed severe enoughremoval if deemed severe enough

CirrhosisCirrhosis

EtiologyEtiology: enlargement of liver (hepatomegaly) : enlargement of liver (hepatomegaly) with normal tissue being replaced with fibrous with normal tissue being replaced with fibrous tissuetissue

S/SS/S: decrease in its function, : decrease in its function, nausea/vomiting, weakness, jaundice, swollen nausea/vomiting, weakness, jaundice, swollen ankles (edema), loss of weight, loss of body ankles (edema), loss of weight, loss of body hair, massive hematemesis, coma, deathhair, massive hematemesis, coma, death

DxDx: patient exam and history, blood results: patient exam and history, blood results TxTx: cessation of causative agent: cessation of causative agent

HepatitisHepatitis

EtiologyEtiology: inflammatory condition, most common : inflammatory condition, most common chronic liver disease; five types: (A,B,C,D,E) chronic liver disease; five types: (A,B,C,D,E) each with differing routes of infection, severity each with differing routes of infection, severity and complications have been identifiedand complications have been identified

S/SS/S: hepatic cell destruction, hepatomegaly, : hepatic cell destruction, hepatomegaly, fever, weakness, nausea, anorexia, arthralgia, fever, weakness, nausea, anorexia, arthralgia, jaundice, skin eruptions, dark urinejaundice, skin eruptions, dark urine

DxDx: patient history, physical exam, blood : patient history, physical exam, blood testing/screeningtesting/screening

Tx: antiviral drugsTx: antiviral drugs

JaundiceJaundice

PancreasPancreas

Endocrine gland that has role in digestionEndocrine gland that has role in digestion 6–9 inches long, located posterior to 6–9 inches long, located posterior to

stomach, and extends laterally from stomach, and extends laterally from duodenum to spleenduodenum to spleen

Secretes buffers and digestive enzymes Secretes buffers and digestive enzymes through pancreatic duct to duodenumthrough pancreatic duct to duodenum

Buffers neutralize acidity of chyme to Buffers neutralize acidity of chyme to protect the intestinal wallsprotect the intestinal walls

Pancreatic EnzymesPancreatic Enzymes

Hormones from the duodenum activate Hormones from the duodenum activate enzyme secretionenzyme secretion

Enzymes:Enzymes: Carbohydrase: works on sugars and starchesCarbohydrase: works on sugars and starches Lipase: works on lipidsLipase: works on lipids Proteinase: breaks down proteinsProteinase: breaks down proteins Nuclease: breaks down nucleic acidsNuclease: breaks down nucleic acids

PancreasPancreas

PancreatitisPancreatitis

Etiology: Inflammation of pancreasEtiology: Inflammation of pancreas Possible causesPossible causes

Blockage of bile duct (causing pancreatic Blockage of bile duct (causing pancreatic enzymes to back up into pancreas)enzymes to back up into pancreas)

Excessive alcohol consumptionExcessive alcohol consumption IrritationIrritation

Pancreatitis cont.Pancreatitis cont.

S/SS/S: severe abd. Pain, N/V: severe abd. Pain, N/V DxDx: physical exam and hx, enzyme levels : physical exam and hx, enzyme levels

elevatedelevated TxTx: depends on severity of symptoms: depends on severity of symptoms

NPONPO Total Parental NutritionTotal Parental Nutrition Pain managementPain management

Pathology Connection: Crohn’s Pathology Connection: Crohn’s Disease Disease

EtiologyEtiology: form of chronic inflammatory bowel : form of chronic inflammatory bowel disease affecting ileum and/or colondisease affecting ileum and/or colon

S/SS/S: pain, cramps, diarrhea, bloating, weight loss: pain, cramps, diarrhea, bloating, weight loss

DxDx: physical exam and history, radiologic studies: physical exam and history, radiologic studies

TxTx: anti-inflammatory meds such as prednisone, : anti-inflammatory meds such as prednisone, surgical intervention if severe surgical intervention if severe

GastritisGastritis

EtiologyEtiology: acute or chronic inflammation of : acute or chronic inflammation of stomach; due to infection, spicy foods, excess stomach; due to infection, spicy foods, excess acid production, stress, alcohol, aspirin acid production, stress, alcohol, aspirin consumption, heavy smokingconsumption, heavy smoking

S/SS/S: pain, tenderness, nausea, and vomiting: pain, tenderness, nausea, and vomiting DxDx: patient history, imaging studies, endoscopy, : patient history, imaging studies, endoscopy,

gastric biopsygastric biopsy TxTx: antacids, antibiotics (if bacterial infection): antacids, antibiotics (if bacterial infection)

IntussusceptionIntussusception

EtiologyEtiology: result of intestine slipping or : result of intestine slipping or telescoping into another section of intestine just telescoping into another section of intestine just below it often in ileocecal region; common in below it often in ileocecal region; common in childrenchildren

S/SS/S: pain: pain

DDx: radiographic studiesx: radiographic studies

TxTx: surgery : surgery

PeritonitisPeritonitis

EtiologyEtiology: infectious and/or inflammatory process : infectious and/or inflammatory process of peritoneum; may be due to leakage of of peritoneum; may be due to leakage of contents from gallbladder, appendix, duodenal contents from gallbladder, appendix, duodenal ulcer, penetrating injuries or result of cancerous ulcer, penetrating injuries or result of cancerous tumortumor

S/SS/S: pain, fever, malaise, shock, abscesses: pain, fever, malaise, shock, abscesses DxDx: patient history, physical examination, blood : patient history, physical examination, blood

workwork TxTx: correction of cause, surgical intervention, : correction of cause, surgical intervention,

antibioticsantibiotics