ChronicPainManagementDanielW.Odell,M.D.AssistantProfessor

DepartmentofAnesthesiology,UniversityofUtahSupportiveOncologyandSurvivorship,HuntsmanCancerHospital

ChronicPain

• Affectsapproximately20%ofthepopulation• Severelyimpactsqualityoflife,sociallife,workforceactivities,overallhealth• Mostcommonpainlocations:• Lowback• Headache• Neckpain• Jointpain• Generalizedpain/fibromyalgia

DiagnosticEvaluationofChronicPain

PainAssessment

• History– OPQRST• Onset• Provocation/Palliation• Quality• Region/radiation• Severity• Timecourse

• History+• Medicationtrialsandresponse

• Adequatedose?• Adequatelengthofmedicationtrial?

• Relatedconditions• Sleep• Function• Mood

• SocialHistory• Substanceabuse• Socialsituation

DiagnosticEvaluation

• Fullphysicalexam• Begentle!• Painbehaviorsandeffort• Neurologicandmusculoskeletalexam• Evaluationofgeneralizedtenderness• Generalizedpainsyndrome• Opioid-inducedhyperralgesia

• Palpationoftriggerpoints

DiagnosticEvaluation

• Characterizetypesofpain�Myofascial� Generalized� Neuropathic� Nociceptive– visceral� Nociceptive- somatic�Mostpatientswillhavemixedpaintypes

• Trytoputitalltogether�Why dotheyhavepain?

Myofascial Pain

Myofascial Pain

• Extremelyunder-recognized!• NotthesameasFibromyalgia– reallyquitetheopposite!• Painresultingfromdisorganizedmusclefibers• Triggerpoints– painradiateswithpalpation• Canmimicradicular painandbeverypainful– morethan“musclepain”• Post-surgical• Deconditioning• Alteredgaitorpositioning

Myofascial Pain

• Gluteusminimus andmedius triggerpointreferralpattern• LookslikeL5radiculitis

Characteristicreferralpatternsoftriggerpoints

SimonandTravells “MyofascialPainandDysfunction:theTriggerPointManual”

Myofascial Pain

• SternocleidomastoidandTrapeziustriggerpoints• Looksliketensionheadache• Canmimicorprovokemigraineheadache

Myofascial Pain• Verytreatable!• Physicaltherapy– morerehab-basedthanorthopedic-based• Experiencewithmyofascialrelease• Experiencewithdryneedling

• Triggerpointinjections• IncombinationwithPT

• Massage• Acupuncture• Theracane/BodyBackBuddy• “TheTriggerPointTherapyWorkbook”

Theracane /BodyBackBuddy

• $35onAmazon.com oroccasionallyatRelaxtheBackstore• Holdtriggerpointwithlight-medium pressurefor10-15sec

NeuropathicPain

• “Painarisingasdirectconsequenceofalesionordiseaseaffectingthesomatosensory system”• Affects3-8%ofpopulation• Characteristics• Burning• Shooting• Electric• Limitedbenefitfromopioids• Mayormaynotbeconfinedtoknownnerve/nerverootdistribution

NeuropathicPain

• Peripheralneuropathy• Phantomlimbpain• Post-herpeticneuralgia• Multiplesclerosispain• Post-surgicalneuropathicpain• Post-injuryneuropathicpain• Chronicradiculopathy• Complexregionalpainsyndrome

PhantomLimbPain

Painperceivedinanabsentbodypart• Variableincidence,60-80%in1st year,maydiminishovertime• ↑incidence:traumaticamputation,upperextremityamputation

Onset§ ImmediateoryearslaterDuration§ Random,recurringintervals§ Canresolvespontaneouslyorpersistforyears

Severity§ For3–10%ofamputees,phantompainischronic&severe

PreventionofPhantomLimbPain• ReferraltospecialistweekstomonthsBEFOREamputationifpossible• InterdisciplinaryTreatmentfocusedon:• Pain:Somatic,Neuropathic,Myofascial• Psychologicalsupport• Physicaltherapy• Familysupport

• MirrorTherapy?• Linksvisualandmotorpathwaystoimagerecreatebody• Reversemaladaptivememorytraces

Medical Physical Psychological Invasive

Gabapentinoids Physicaltherapy Explanation StumprevisionTCAs Mirrortherapy GuidedImagery Neuroma

resection

SNRIs Prosthesisadjustment

Relaxation Spinalcordstimulation

Anticonvulsants Stumpdesensitizing

Behavioraltherapy

Thalamic/cortexstimulation

Beta-blockers Acupuncture HypnosisKetamine Stumpmassage Biofeedback

LidocaineIV TENS Psychotherapy

TreatmentofPhantomLimbPain

Post-HerpeticNeuralgia

• Painthatpersistsaftershinglesinfection• Unilateral,dermatomal

• Increaseincidencewithage• 80%inpatients80yo

• Severeburning,shootingpain+/-skinhypersensitivity• Morecommoninimmunosuppressedpatients• Earlytreatmentassociatedwithimprovedoutcomes

Post-HerpeticNeuralgia

•Prevention• Antivirals infirst48hoursofshinglesoutbreak• Zostervaccineif>60yoorprioroutbreak

• Treatment• NeuropathicAgents

• InterventionalTherapies• Stellate Ganglionblock• Face/upperextremity

• Epiduralsteroidinjection• Thorax/abdomen

ComplexRegionalPainSyndrome• Spectrumofdiseasebutveryspecific

• Not“PainNOS,”NotReflexSympathyDystrophy(RSD)

• Continuouspain,disproportionatetoanyincitingevent• Historyofonesymptomin3categoriesandpresenceatthetimeofevaluationofsymptomsin2categories:• Sensory– hyperesthesia,allodynia• Vasomotor– temperatureasymmetry,skincolorchanges• Sudomotor/Edema– swelling,sweating• Motor/Trophic – decreasedrangeofmotion,motordysfunction,trophic changes

• Nootherdiagnosisthatbetterexplainsthesigns/symptoms

ComplexRegionalPainSyndrome

• Uncommontobepresentinmorethan1bodypart• Thereisnosuchthingas“Full-bodyCRPS”thoughCRPShassystemiceffects

• Variableprogressionovertime– overallfavorable• Returnoffunctionandreliefofpainassociatedwithearlyandaggressivecare

• Treatment• Physicaltherapywithdesensitizationfollowedbyincreasingflexibility,rangeofmotionandstrength

• Pharmacotherapywithanti-neuropathicagents• Sympatheticnerveblockstofacilitatephysicaltherapy• Moreinvasivetherapiesifneeded(spinalcordstimulator)

ComplexRegionalPainSyndrome

ComplexRegionalPainSyndrome

• Physicaltherapy• Experiencedprovider• Desensitizationtherapy• Mirrortherapy• Increasingrangeofmotionslowly

• Sympatheticnerveblocks• UsedtofacilitatePTandbreakcycleofpain

• Neuropathicmedications

GeneralizedPain

GeneralizedPainSyndromes• Widespreadpainthroughoutthebody• Notmultiplelocationsbutcontinuousinjoints,softtissue,etc

• Variablequality,usuallynoincitingevent• Diffusetendernesstopalpationthroughoutbodyonexam• Absenceofsignificanttriggerpoints

• Associatedwithdepression,poorsleep• Thoughtduetocentralsensitization

Fibromyalgia

• Specificdiagnosiswithin“GeneralizedPainStates”• Specificdiagnosticcriteria• Incorporatessleep,cognitivesymptoms,othersomaticsymptomsintodiagnosis

• NOTTHESAMEASMYOFASCIALPAIN• Affects2-4%ofthepopulation,femalepredominance• Oftenbeginsinmiddleadulthood

Fibromyalgia

GeneralizedPainStates

• Treatment• Physicalactivity!

• Startat5min/day,workupto30min/dayaerobicactivity

• Verygradual• Sleephygiene• Treatmentofconcurrentmooddisorders• Gabapentin/Pregabalin,Duloxetine,?TCA,NSAIDs,tylenol• Opioidsnotindicated!

• Noteffectiveandmaycontributetohyperalgesia

NociceptiveVisceralPain

NociceptiveVisceralPain

• Painresultingfromthoracic,abdominalorpelvicviscera• Distension,ischemia,inflammation

• Poorlylocalized• Dull,aching,pressure,squeezing• Notparticularlymovement-related

VisceralPain

• Referredtosuperficialstructures• Diaphragmà Shoulder• Anginaà Leftneck/arm

• Chronicabdominalandpelvicpain• Cancerpain

NociceptiveSomaticPain

NociceptiveSomaticPain• Arisesfromdamageorinjurytobone,joint,muscle,skinorconnectivetissue• “Mechanical”pain

• Well-localized• Intenseache,throbbing,sharp,stabbing,pinprick• Bonypain

• Metastases,fractures• Degenerativespinedisease

• Jointpain• Osteoarthritis

TreatmentApproachtoChronicPain

TreatmentAlgorithm• Conservativetreatment• Physicaltherapy,Pooltherapy• Behavioraltherapy• Complementarymedicine– acupuncture,massage,acupressure• Tylenol,NSAIDs

• Adjunctmedications• Neuropathicagents,antidepressants,topicalagents,musclerelaxants

• Injections/Procedures• InvasiveProcedures/ImplantedDevices

ConservativeTreatment

ConservativeTreatment

• PhysicalTherapy• Onesizedoesnotfitall!• Earlyinstitution• Experiencedproviders• Tailoredtreatment

• PoolTherapy

ConservativeTreatment• BehavioralMedicine• RelaxationTherapy• BehaviorModification• Education• Biofeedback• Counseling/Therapy– CBT• Hypnosis

• Beneficialforall!• Recognizetheimpactofmoodonpainandvisaversa• Centralsensitization

ConservativeTreatment

• Complementarymedicine• Acupuncture• Acupuncture• Massagetherapy• TaiChi• Mindfulnessmeditation

Acetaminophen

• Analgesicandantipyretic•Mechanismofactionpoorlyunderstood

• Blocksprostaglandinsynthetase inCNS,notperipherally• Lacksperipheralanti-inflammatoryeffects• Lacksplatelet,GI,bone,renaleffects

First-linetreatmentforpainintheelderlyMaximum3000-4000mg/day

• Beawareofothertylenol-containingproducts• 2000mg/daywithhepaticdisease

NSAIDsCOXInhibitors:Preventinflammatorycascade

NSAIDs

NSAIDsTwoisoformsofCOXenzymeCOX-1◦ Constitutive◦ “Housekeepingenzyme”◦ GItract◦ Kidneys◦ Platelets

COX-2◦ Induciblewithinflammatorystimulus

NSAIDs

• Aspirin• Ibuprofen• Ketorolac• Naproxen• Indomethacin• Diclofenac• Meloxicam• Etodolac• Celecoxib

Non-Selective,TemporaryCOX-Inhibitors

Selective,TemporaryCOX-2Inhibitors

Non-Selective,PermanentCOX-Inhibitor

NSAIDs AdverseEffects

GI- Gastritis,gastric/pepticulcersHematologic– IncreasedriskofbleedingOrthopedic– Impairedbonehealing?Renal- AcutekidneyinsufficencyCardiovascular- IncreasedriskofMI

DecreasedincidencewithCOX-2Inhibitor

NSAIDs

• ALWAYSTAKEWITHFOOD• ConsiderconcurrentPPIuse• Naproxen375- 550mgbid• Meloxicam7.5-15mgdaily

• 7.5mgdoseisCOX-2selective

• Celebrex100-200mgbid– easiestonGIsystem,saferwithanticoagulants,expensive• Ibuprofen600-800mgtid• IncreasedriskofAKI

HotOffthePress!

• “TakinganydoseofNSAIDsforoneweek,onemonth,ormorethanamonthwasassociatedwithanincreasedriskofmyocardialinfarction.”

AdjunctMedications

AdjunctMedications

•Gabapentinoids• Gabapentin• Calciumchannelblocker• 300mgqhs withtitrationtototaldailydose1800-3600mg(startwith100mgqhs withtitrationto300mgtid inelderly)

• Neuropathicpain,generalizedpain,opioid-sparing• Pregabalin• Calciumchannelblocker• 50mgqhs withtitrationtototaldailydose300-600mg• Neuropathicpain,generalizedpain,opioid-sparing

AdjunctMedications

• Antidepressants• Tricyclic antidepressants

• Amitriptyline andImipramine – tertiaryamines,moresideeffects

• Nortriptyline andDesipramine – secondaryamines,lesssideeffects• Desipramine causesleastamountofsleepiness

• Startat25mgqhs,titrateto100mgqhs astolerated(lessinelderly)

• Cautionwithotherseratonergicmedications,elderlypatients• SNRIs• Duloxetine(60-120mg/day)• Venlafaxine?• Evidenceisunderwhelming

AdjunctMedications

•Anticonvulsants• Topiramate• Sodiumchannelblocker• Poorevidenceinpainotherthanmigraineprophylaxis

• Carbamazepine/Oxcarbazepine• Sodiumchannelblockers• Trigeminalneuralgia

AdjunctMedications

•MuscleRelaxants• Workbestwithshort-termuse(10days),tolerancedevelopsquickly• Cyclobenzaprine5-10mgtid• TCA-like,cautionwithotherseratonergicmedsandintheelderly

• Tizanidine2-8mgtid• Valium,Soma(carisoprodol),Robaxin (methocarbamol),Skelaxin(metaxaolone)• CNSsedatives– notmusclerelaxants.Avoid.• SomaisadangerousCNS-depressantandimplicatedinmanymultidrugunintentionaloverdosedeaths

AdjunctMedications•TopicalAgents•Voltaren gelorFlector patch• Diclofenacpreparations– gelnowgeneric• Applytoaffectedarea• Greatforpatientsonoralanticoagulation• Worksbestwhenpainfulareaisclosetotheskin• Knees,finger/toes,etc

•Compoundedcreams• Expensiveandineffective• Exceptionmaybeketamine creamforallodynia

OpioidMedications

PainandAddiction

• Chronicpainiscommon• Occursin33%ofthepopulation,severein10%

• Opioidsarefrequentlyprescribedforpain• 16%ofpatientsinprimarycaresettingin2002

• Opioidmisuseandaddictionarecommon• Fishbain 2007

• 11.5%ofchronicpainpatientsmisuseopioids• 3.5%ofchronicpainpatientshavedevelopopioidaddiction• 14.5%ofchronicpainpatientsuseillicitdrugs

Whentoconsideropioids• Appropriatetypeofpain

• Notmyofascial pain• Notgeneralized/fibromyalgiapain

• NEVERfirstline• Conservativetreatment• Adjunctmedications• Physical,behavioral,complementarytherapies

• Failureofmultiplepasttrialsofmedication/therapies• Willitimprovefunction??

InitiationofOpioids• Documentationofpainandpriorinterventions,therapiesandmedicationtrials• Psychologicalassessment• Substanceabuseassessment

• Risk/benefitdiscussionwiththepatient• Medicationagreement• Specifywhocanprescribeopioids• Whocanprescribeothercontrolledmedications• Managementofacutepain

• Considerbaselineurinedrugscreen

InitiationofOpioids

• Trialofopioids• Lowdose(Hydrocodone 5/325bid-tid)• Mildescalationreasonable(approaching30-50mgOME?)

• Assessmentofimprovement• Pain• FUNCTION!

• Routinely assess4A’s• Analgesia• Activity• AdverseEffects• AberrantBehavior

CasualPrescribingofOpioids

• Ifyoustartopioidsyouhavebecomethatpatient’sopioidprescriber• Maybereasonableforacuteissues• Importantforpatienttohaveappropriateexpectations• Duediligence

• ControlledSubstanceDatabasereport• Knowledgeofothersedatingmedications• Healthhistory

• Donotgiveopioidsandtellapatientanotherprovider(PainSpecialist,Surgeon,Dentist)willgivethemmore

Pre-ExistingOpioids• Managementofpatientsalreadyonopioids• Sameconsiderations

• Appropriatetypeofpain• Failureofmultipletherapiesandnon-opioidmedications• Psychologicalassessment• Substanceabuseassessment• Risk/benefitdiscussionwiththepatient• Medicationagreement

• Ifnotappropriateinformthepatientanddevelopplanforopioidtaperwithinitiationofothertreatment• Youarenotbeholdentoprescribeopioidsjustbecauseanotherpractitionerhasdoneso• Howevertaperingovertimecanpromotetherapeuticrelationshipwithpatient

Preventionofopioidmisuse/abuse

•Prescriberfactors• Dose• Risksincreaseabove100mgOME,skyrocketover200mgOME

• Concurrentcontrolledsubstances• Risksincreasewithconcurrentbenzodiazepinesorhypnotics

• “Musclerelaxants”otherthantizandine/cyclobenzaprine• Sleepaids:Ambien/Lunesta/Sonata,temazepam• Onlyone?Onlytwo?

CDC.CDCgrandrounds:prescriptiondrugoverdoses-aU.S.epidemic.MMWRMorb MortalWkly Rep2012;61:10-3.

Detectionofaberrantopioid-relatedbehaviors

AberrantBehavior

• Lostopioid prescriptions• Outofopioids early• InappropriateDOPL• InappropriateUDS• Failuretoparticipateinnon-opioid treatment• Concernforopioid diversion• Overtsedation

AberrantBehavior

• Safetyofpatientandcommunityisfirstconsideration• Verifythefacts• Controlledsubstancedatabasereport• Callpatient’spharmacyorotherproviders• RequestrecordsfromED/Hospital

• Basedecisiononcontinuedprescribingonsafety,factualinformation,painissueandinformthepatient• Provideresourcesforopioidwithdrawal

Detectionofaberrantopioidbehaviors• UrineDrugScreening• Presenceofexpectedmedicationsandmetabolites• Absenceofillicitsubstancesorotheropioids• Onlyasgoodasyourtest!

• Falsepositivesandnegativesexist– knowyourpatientandtest• High-resolutiontestinEPIC• ARUPpathologistsoncalltotroubleshoot/answerquestions

• Howoften?• PRIORtoinitialprescribing• Q3-12months• Witnessed?• Orjustmakesuretheydon’ttakeanythingintothebathroom?

Detectionofaberrantopioidbehaviors

• PrescriptionDrugMonitoringPrograms(DOPL)• Everytimeyouseeapatientorrefillamedication• Hopefullyeventuallynationwide• CansetsurrogatestoaccessthisunderyourlicenseinUT

• 3RNsorMas

• PillCounts• Requirecoordinationofstaffandpatient

• Requestsforearlymedicationrefills• Reportsfromfamily/friends

• Canlistentoanyinformation,maynotdiscloseany• Finelinetowalk

ManagementofaberrantopioidrelatedbehaviorThehardstuff

Managementofaberrantbehavior• Safetyofpatientandcommunityisfirstconsideration• Verifythefacts• Controlledsubstancedatabasereport• Callpatient’spharmacyorotherproviders• RequestrecordsfromED/Hospital

• Basedecisiononcontinuedprescribingonsafety,factualinformation,painissueandinformthepatient• Provideresourcesforopioidwithdrawal

• Youmustcontinuetocareforpatientsfor30daysafterclinicdischarge– thisdoesnotimplyprescribingopioids

• Dependsonseverity• “Common”- Earlyrefills,inappropriateUDS/DOPL/PillCount

• Verifythefacts,givethepatientanopportunitytoexplain• Reasonablepractice

• Firststrikeincursawarning– documentit!• Secondstrike=nocontinuedopioidprescribing

• Concurrentillicitdruguse• Nofurtheropioidprescribing(marijuana?)

• Confirmedoverdose• Nofurtheropioidprescribing

• Confirmeddiversion• Dischargepatient

• Youmustcontinuetocareforpatientsfor30daysafterclinicdischarge– thisdoesnotimplyprescribingopioids

Managementofaberrantbehavior

InjectionProcedures

ChronicSpinePain•Mechanical• Scoliosis,arthritis,stenosis,degenerative• Facetarthropathy,sacroiliacjointarthropathy• Failedback/necksurgerysyndrome

EpiduralInjections• Epiduralinjections• Localanesthetic+steroidinjectedintoepiduralspacesurroundingnerveroots• Clearsinflammatorymediatorsandreducesinflammation/compression

• Indicatedforradicular upperextremityorlowerextremitypain• Burning,shootingpaininspecificdistributiontodistalareaoflimb• Neurologicdeficitsà radiculopathy,“just”pain– radiculitis

• Alsoindicatedforspinalstenosis andpostherpeticneuralgia• Differentapproachesdependingonnatureandlocationofpain• Relieflasts2-4monthsonaverage

FacetArthropathy• Painjustoffmidline,worsewithextension/rotation• Doesnotcauseradicular painbutpaincanradiatelocally• Candevelopduetoarthritis,misalignment• Injections:• Thermalablationofnervebranchthatinnervatesthejoint(older)• Lasts6-9months,canberepeated

• Intra-articularsteroidinjections(younger)• Lesseffective

SacroiliacJointInjection

• Jointatintersectionofspineandpelvis• Significantmovementandweightloading

• Candeveloppainduetoarthritisormisalignment

• PainoverSIjointwithradiationintobuttockandposteriorthigh• “FABER”provokespain

• flexion,abductionandexternalrotationofhip• Localanesthetic+steroid,lasts3-4months

SacroiliacJointDysfunction

PeripheralNerveInjections

• Ilioninguinal NerveBlock:• Indications:Ilioinguinalneuralgia(groinpainafteringuinalsurgery/tumor)• Steroid+localanesthetic–lastsapprox3months

PeripheralNerveInjections

nOccipitalNerveBlock:n Indications:Occipitalneuralgia(occipitalpain/HAaftersurgeryortumor)

n Steroid+localanesthetic–lastsapprox3months

PeripheralNerveInjections

•Genicular NerveBlock• Indications:Chronickneepain,notoperativecandidate• Diagnosticnerveblockwiththermalablationifsuccessful• Success50/50

PeripheralNerveInjections

IntercostalNerveBlock◦ Indications:Intercostalneuralgia,Chronicribpain(post-thoracotomy)

◦ Localanesthetic+steroid

JointInjections

•Hip,Knee,Shouldermostcommon• Painfulosteoarthritisofjoint• Dx withx-ray

• Steroid+localanesthetic– lastsapprox3months• Hyaluronate viscosupplementationforkneesmaylast6-12months• Ultrasound,fluoroscopy,“blind”

InvasiveInjectionsandImplantedDevices

SympatheticBlocks

• Diagnostic• Isthepainsympatheticallymediated?

• Therapeutic• Localanesthetic– breakthecycle• Seriesofsympatheticblocks+PTforCRPS

• Steroid– littleevidence• Chemicalneurolysis– denaturethenerves

• TerminalCancer

SympatheticBlocks

• Stellate Ganglion• Neuropathicpainoftheface,neck,shoulderorupperextremity• CRPS,PhantomLimb,PHN

LumbarSympatheticBlock• Neuropathic,suspectedsympathetically-mediatedpaininthelowerextremity• CRPS,Phantomlimbpain,Ischemicpain/vascularinsufficiency

SpinalCordStimulationNeuromodulation:providealternateinputtospinalcordto“coverup”pain• Leadsimplantedinepiduralspaceconnectedtoanimplantedbatterysource

• Patientsundergo“Trial”firstwithtemporarypercutaneousleadsfor3-7days• Multipledevicecompanies,stimulationmethods/parameters• InternationalNeuromodulation Society:http://www.neuromodulation.com/spinal-cord-stimulation

SpinalCordStimulation

• Indications:• Neuropathicpaininlimbs

• Persistentradicularpain,phantomlimbpain,postherpetic neuralgia,brachialplexusinjury

• Failedback/necksurgerysyndromeRapidlyChanging• High-frequencySCS:Effectiveforaxiallowbackorneckpain?• DorsalRootGanglionSCS:Groinpain,ilioinguinal pain,intercostalpain,radiculopathy?

• Newwaveforms/programmingtechniques:Burst,high-density,etc.

SpinalCordStimulation

•Downsides:• Invasive• Complications• Infectionrate5-10%

• Diminishedeffectovertime(5+years)• Maybelesswithnewerwaveforms

• Doesnottreatmyofascial ormechanicalpain• NotallsystemsareMRI-compatible

PeripheralNerveStimulation

• Similartospinalcordstimulation• Indicatedforspecificnerves• Occipitalneuralgia• Ilioinguinal neuralgia

• Mayhavearoleinchronicmigraine• Emergingfield• Insurancecoveragechallenging

Conclusion• Diagnosis:history,physicalexamandcharacterizationofpaintypes• Myofascial,Generalized,Neuropathic,Nociceptivevisceral,Nociceptivesomatic

• TreatmentAlgorithmtailoredtopaintypes• Conservativetreatment• Adjunctmedications• Injections/Procedures• InvasiveProcedures/ImplantedDevices

Thanksforyourattention!

Acknowledgements- JillSindt,M.D.- PerryFine,M.D.- PainManagementCenter,UniversityofUtah- SupportiveOncologyandSurvivorship,HuntsmanCancerHospital

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• ClarkJD.ChronicPainPrevalenceandAnalgesicPrescribinginaGeneralMedicalPopulation.JPainSymp Manage2002;23(2):131-37

• Fishbain,DAetal.2007.Whatpercentageofchronicnonmalignantpainpatientsexposedtochronicopioid analgesictherapydevelopabuse/addictionand/oraberrantdrug-relatedbehaviors?Astructuredevidence-basedreview.PainMed.9,444–459.

• WilliamC.Beckeretal.Non-medicaluse,abuseanddependenceonprescriptionopioidsamongU.S.adults:Psychiatric,medicalandsubstanceusecorrelates.DrugAlcoholDepend2008:94:37-47.

• Okie,Susan.Afloodofopioids,arisingtideofdeath.NEngl JMed2010;363:1981-1985

ThankYou!