Gastroenterology & Hepatology Volume 7, Issue 11 November 2011 753

Endo

scop

y

AdvAnces in endoscopy

section editor: John Baillie, MB chB, FRcp

C u r r e n t D e v e l o p m e n t s i n D i a g n o s t i c a n d T h e r a p e u t i c E n d o s c o p y

Update on Endoscopic Approaches to Nutritional Support

Mark H. DeLegge, MDProfessor of Medicine Division of Gastroenterology and HepatologyMedical University of South CarolinaCharleston, South Carolina

G&H Could you discuss the current use of percutaneous endoscopic gastrostomy tubes for enteral nutrition?

MHD Percutaneous endoscopic gastrostomy (PEG)tubeshavebeenusedforapproximately30years.Theywere originally designed for use in children and havebecome a fairly standard part of gastroenterology andsurgical endoscopy. The various kits that have beendeveloped for placement of PEG tubes have similarcomponents: a PEG tube and instrumentation formaking an incision to obtain access to the stomach,an external bolster for stabilizing the position of thetube,andanadapterontheendofthetubeforfeeding.Placementofthesetubesrequires2individuals(usuallyaphysicianandanurse).Theprocedurehasincreasedinvolumeovertheyears,most likelybecausethegeneralpopulation is becoming older, and older patients aretypically the ones who develop chronic diseases thatrequirefeedingtubes.

Percutaneousendoscopicgastrojejunostomy(PEG-J)isperformedinpatientswhocannotreceivefoodintothestomachand,thus,havetobefedviathesmallintestine.In this procedure, a standard PEG tube is placed, andthenasmallertube(ajejunaltube)isplacedthroughthePEGtubeandpositioneddownintothesmallintestine.Theinnertube(the jejunal tube) isusedfornutritionalsupport,whereas theouter tube (thePEGtube)canbeused to administer medications into the stomach or todecompressthestomach,ifnecessary.

PEG-J systems, particularly the jejunal tubes, aremorecumbersomeanddifficulttoplacethanPEGtubes.AlthoughPEG-Jtubeshavebeenshowntoprovidebene-fits,manygastroenterologistsstrugglewithpositioningthistubesystemand,thus,avoiddoingsobyreferringthisjobtoradiologists.Idonotagreewiththistendency;Ithinkthattheprocedurecanbelearnedquiteeasilywithpractice.

The disadvantage of PEG-J systems is that thejejunal tube may migrate backward into the stomach;thus, itmay appear thatpatients arebeing fedvia thesmallintestine,but,infact,thejejunaltubehasactuallymigrated back into the stomach, so patients are beingfed via the stomach, which is what gastroenterologistsweretryingtoavoidinthefirstplace.PEG-Jisnottheappropriate tube system for patients who will requirejejunal feedingfor therestof their lives; this systemismosteffectiveasabridgeforpatientswhomightneedsmallbowelfeedingonlyforseveralmonths.

Anothertechnique,whichhasgrowninprominenceover the past 10 years, is direct percutaneous jejunos-tomy.Thisprocedureinvolvestheplacementofafeedingtubedirectly into the smallbowel (rather than into thestomachviaaPEGtube).Aswithanyprocedure, thereisalearningcurve;however,thisprocedureappearstobesafe.Ultimately,directpercutaneousjejunostomyshouldbecomepartofendoscopists’armamentariumfor thera-peuticnutritionalinterventions.

G&H Could you expand on how the use of these feeding tubes has changed over time?

MHD Originally, PEG tubes were used only in chil-dren and patients with terminal diseases (eg, patientswhowereunabletoswallow,perhapsduetoesophagealcancer, end-stageParkinsondisease, or amajorneuro-

754 Gastroenterology & Hepatology Volume 7, Issue 11 November 2011

Endo

scop

y

logicproblem).Overtheyears,PEGtubeshaveshownefficacy in certain patient populations, although theyhave had questionable utility in other patient popula-tions.Forexample,PEGtubeshavebeenveryeffectivein patients with head-and-neck cancer, patients withesophageal cancer, andpatientswhohavehadamajorstroke but are otherwise functional. However, therehavebeenquestionsregardingtheuseofPEGtubesinpatientswithend-stagedementiawhohavelosttheabil-itytoswallow.Endoscopistsaresometimescriticizedforplacingtubesinthesepatients,whoareneardeathandperhaps should not undergo this procedure. However,as alldementiapatients arenot the same, I think thatthe decision of whether to place feeding tubes shouldbedeterminedonacase-by-casebasis.Nevertheless,wehavetorememberthatinsertingafeedingtubewillnotsavethelifeofaterminalpatient,althoughitmayhelpimprovethepatient’squalityoflife.

PEG-J has answered the question of how endos-copists can place a feeding tube into the small bowelwithout the help of a surgeon or a radiologist andwithoutcreatingapuncturesite in thesmall intestine.PEG-J enables access to the small bowel by placing ajejunaltubethroughapreexistingPEGtube.Overtheyears,wehaveseenthatendoscopistscanbecomequitecompetentatperformingthisprocedure.However, theprocedureisnotpermanent;thejejunalfeedingtubeissmall indiameterandlight inweight,whichresults inocclusionandmigration.EffortsarecurrentlyunderwaytoredesignthePEG-Jsystem,sothatthejejunaltubeislargerandlesslikelytoclogormigrateoutofposition.

G&H Do you anticipate any other major changes in the technology of these tubes or in their applications in the near future?

MHD Overthenext5–10years,Iforeseechangesthatwill improve patient and clinician safety and reducecomplications associated with PEG tube placement.For example, the most common complications associ-atedwithPEG tubeplacement are bleeding, infectionaroundthe tube,orperitubular leakageofgastriccon-tentsaroundthe tubeandonto thepatient’s skin.Thematerials and construction of the tubes are currentlybeingredesigned toaddresssomeofthesecomplicationsby making the tubes less irritating to tissue—whichwould improve a patient’s ability to tolerate the tubelongtermandimprovewoundhealing.

Inaddition,wearestartingtolookmorecarefullyattheplacementprocedureandarequestioningwhetheritistrulysterileornearsterile.Althoughtheendoscopistuses a sterilegownandgloves, theprocedure isnot assterileasoneperformed inanoperatingroombecause

thePEGtubecanbecomecontaminatedduringplace-ment.Overthenextseveralyears,Iforeseeredesignofthetubetominimizethisproblem.

Interestingly,PEGtubesintheUnitedStatestendtobelargerinsizethanthoseusedintherestoftheworld.Therehasbeenmuchdebateregardingthisdifference.Ipredictthattherewillbeashifttoamiddle-of-the-roadapproach:tubesthatarenottoobigbutthatarenottoosmallinsize.

WithregardtothePEG-Jprocedure,Iforeseeinno-vationaimedataidingtheendoscopistinpositioningthejejunal tubebysimplifyingtheprocedure; insteadofanhour-longstruggle,thegoalshouldbetoplacethejejunaltubein10–15minutes.Designchangeswilllikelyaddresscomplications associated with the procedure, such astubeobstruction(bydevelopinglargerjejunaltubes)andmigration(perhapsbychangingtheshapeofthetubesorhowtheyrestorattachtothesmallbowel).

G&H Have there been any recent developments in feeding solutions?

MHD Over the years, the development of feedingsolutions has waxed and waned. As feeding solutionsfallunder thecategoryof food substances, theapprovalprocessbytheUSFoodandDrugAdministration(FDA)differs from the approval process associated with drugdevelopment.Recently,wehaveseenamovetowardmorespecializedtubefeedingsolutions(ie,solutionswithphar-maconutrient properties). For example, some solutionsarenowbeingmadewithfishoil,glutamine,orarginine.Othertypesofmodifiedlipidsarebeingplacedintosolu-tionsaswell.Thesenewsolutionsareusingnutrientsasmechanismsforchangingpatients’outcomesbyimprov-ingfactorssuchasimmuneresponseandoxidativestress,particularlyincriticallyillpatients.

G&H Is nutritional support needed in patients with gastrointestinal diseases?

MHD There are several gastrointestinal (GI) diseasesthatareparticularlyaffectedbynutrition.Inthepast,allpatients with pancreatitis were considered nil per os; iftheyneedednutrition,itwasadministeredintravenously(viaparenteralnutrition).However,overthepast10years,wehavelearnedthatmanyofthesepatientscanbefedviathegut,usuallythesmallbowel(viaenteralnutrition).Infact, studieshaveshownthatpatientoutcomes improvewiththeuseofenteralnutritioncomparedtoparenteralnutrition.Pancreatitispatientsreceivingenteralnutritionexperience fewer complications, shorter hospital stays,andimprovedhealthcareeconomicbenefits.

Nutrition also plays a role in inflammatory boweldisease,particularlyCrohn’sdisease,wheremacronutrient

Gastroenterology & Hepatology Volume 7, Issue 11 November 2011 755

Endo

scop

y

deficiencies can occur. These deficiencies can be foundinchildren,wheretheycanleadtogrowthfailure,orinadults,wheregastroenterologistsmaybemorefocusedonbowelmovementsorrectalbleedingthanonthepatient’snutritionalstatus; inthiscase,anaggressiveapproachisneeded for nutritional maintenance: either a change indiet,initiationofsupplementalenteralnutrition,orpos-siblyeveninitiationofparenteralnutrition.

Another area of nutritional importance involvespatientswithGIcancers,includingesophagealcancers,gastric cancers, pancreatic cancers, and small bowelcancers.Thesepatients tendtobeanorectic fromtheircancer; they are also usually hypermetabolic and haveaGI tractdysfunction thatprevents themfromeatingnormally.Over the years,wehave seen that treating apatient’s tumor,butnottheirnutritionalstatus,resultsinverypooroutcomes.Itiscommonforcancerpatientstobemalnourished;itislesscommonforphysicianstoinstitute aggressive nutritional support simultaneouslywithtumortreatment.

Nutritional support is also important in patientswithterminalcancer,suchasperitonealmetastasis fromatumorandresultantsmallbowelobstruction.Althoughthese patients may have only 4–6 months to live, theirqualityoflifemaydramaticallyimprovewiththeuseofaggressivenutritionalsupport.

G&H What is your perspective on current and evolving endoscopic techniques for weight loss?

MHD The development of an endoscopic obesitydeviceintheUnitedStateshasbeenalonganddifficultjourney.TherewerehighhopesfortheGarron-Edwardgastric bubble, but, unfortunately, it was associatedwith complications.At that time, itwas thought thatthe procedure could be performed and the patientcouldbe senthomeandwould loseweight.Later,we

realized  that other medical professionals need to beinvolved,suchasadieticianandbehavioraltherapist.

Recently, the difficulties in this journey haveinvolvedtheFDA,whichhasdeclaredthatendoscopicapproaches to obesity treatment must be as effectiveas surgical treatments for obesity. However, it is notrealistic to expect the same outcomes from a majorsurgicalprocedureandfromplacementofadeviceinthestomachorsewingtheinsideofthestomach.Cur-rently,wearetryingtomaketheFDAunderstandthatthereshouldbeatreatmentoptionbetweendiet/exer-ciseandsurgery.Apatientwithahighbodymassindex(BMI; eg, 40 kg/m2) may do better with a surgicalinterventionforobesity,whereasendoscopictreatmentmay be more appropriate in patients with a BMI ofapproximately30kg/m2whohavebeenunsuccessfulwithdiet,education,andexercise.

Over thenext5years, I anticipatemore success inthisarea.Severaldevicescurrentlybeingusedinternation-allyarehavingsomesuccess.IntheUnitedStates,IthinkwewillhavetocompromisewiththeFDA,butwewillhaveatleastonetherapeuticendoscopicdeviceavailableforplacementinobesepatientsinthenearfuture.

Suggested Reading

DeLeggeMH.Percutaneous endoscopic gastrostomy.Am J Gastroenterol. 2007;102:2620-2623.

ItkinM,DeLeggeMH,FangJC,etal.Multidisciplinarypracticalguidelinesforgastrointestinalaccess forenteralnutritionanddecompression fromtheSocietyofInterventionalRadiologyandAmericanGastroenterologicalAssociation(AGA)Institute,withendorsementbyCanadianInterventionalRadiologicalAssociation(CIRA) and Cardiovascular and Interventional Radiological Society of Europe(CIRSE).Gastroenterology.2011;141:742-765. 

DeLeggeMH.Endoscopicapproachesforthetreatmentofobesity:factorfiction?Nutr Clin Pract.2011;26:534-538.

GigerU,StangaZ,DeLeggeMH.Managementofchronicpancreatitis.Nutr Clin Pract.2004;19:37-49.

DeLeggeMH.Enteralfeeding.Curr Opin Gastroenterol.2008;24:184-189.