J. Coloproctol. (Rio J.) vol.37 número4

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w w w . j c o l . o r g . b r

Journal

of

Coloproctology

Original

Article

Factors

associated

with

abdominal

pain

in

patients

submitted

to

colonoscopy

夽

Amanda

Colpani

Bellei

∗

_,

_Daniela

_Ghizoni

_Dacoregio,

_Flávio

_Bianchini,

_Jaime

_César

Gelosa

Souza,

João

Martiniano

Lamim

Bello,

Kaiser

de

Souza

Kock

UniversidadedoSuldeSantaCatarina(UNISUL),DepartamentodeMedicina,Tubarão,SC,Brazil

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r

t

i

c

l

e

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n

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o

Articlehistory: Received5July2017 Accepted26August2017

Availableonline23September2017

Keywords: Colonoscopy Conscioussedation Abdominalpain Sedation

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b

s

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t

Objective:Thestudyevaluatedfactorsassociatedwithabdominalpainduringcolonoscopy. Methods:Thiswasacross-sectionalobservationalstudythatevaluatedpatientswho under-wentcolonoscopy between February 2014 and February 2015. Physical characteristics, surgicalhistoryandpreviouscolonoscopies,indicationandcurrentexaminationconditions, fentanylandmidazolamdose,andpainlevelwereanalyzed.Significanceleveladopted: p<0.05.Chi-squaredtestwasusedforassociationofcategoricalvariables,Student’st-test wasappliedforcomparisonofmeans,andSpearman’scoefficientwasusedforcorrelation. Results:Atotalof566womenand391menwithmeanageof54.81yearsandmeanBMIof 27,064wereevaluated.Ofthetotal,29(3.0%)hadmildpain,42(4.4%)hadmoderatepain, and18(1.9%)hadseverepain.Womenwerelesstolerant(p=0.011)andhadlongercecal intubationtimes(p=0.001).Meandurationofcolonoscopyandmeandoseofmidazolam werehigherinpatientswithpain(p=0.001),(p<0.001*).Amongthe39 patientswithan incompleteexamination,8reportedpain(p=0.049).

Conclusion:Femalegenderandprolongedintubationtimeweresignificantlyassociatedwith abdominalpainduringcolonoscopy.Patientswithdiscomforthadahigherfailurerateon theexam.Additionaldosesofmidazolamgiventopatientswithpainwerenoteffective.

creativecommons.org/licenses/by-nc-nd/4.0/).

Fatores

associados

à

dor

abdominal

em

pacientes

submetidos

à

colonoscopia

Palavras-chave: Colonoscopia Sedac¸ãoconsciente

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u

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o

Objetivo:Oestudoavalioufatoresassociadosàdorabdominalduranteacolonoscopia. Métodos:Estudoobservacionaltransversal,queavalioupacientesquerealizaram colono-scopia entreFevereiro de 2014 e Fevereiro de 2015. Analisou-se características físicas,

夽

StudyconductedattheClínicaPró-Vida,Servic¸odeEndoscopiaeColonoscopia,Tubarão,SC,Brazil. ∗ _{Corresponding}_author_.

E-mail:amandabellei@hotmail.com(A.C.Bellei).

https://doi.org/10.1016/j.jcol.2017.08.003

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Dorabdominal Sedac¸ão

históricocirúrgicoecolonoscopiasprévias,indicaçãoecondiçõesdoexameatual,dosede fentanilemidazolameníveldedor.Níveldesignificânciaadotado:p<0,05.Utilizou-seteste Qui-quadradoparaassociaçãodevariáveiscategóricas,testetdeStudentparacomparação demédiasecoeficientedeSpearmanparacorrelação.

Resultados: Avaliou-se566mulherese391homens,commédiadeidadede54,81anose IMCmédiode 27,064.Dototal,29 (3,0%)tiveramdorleve,42 (4,4%)dor moderadae18 (1,9%)dorintensa.Asmulheresforammenostolerantes(p=0,011)etiverammaiortempo deintubac¸ãocecal(p=0,001).Adurac¸ãomédiadacolonoscopiaedosemédiade midazo-lamadministradaforammaioresnospacientescomdor(p=0,001),(p<0,001*).Entreos39 pacientescomexameincompleto,8relataramdor(p=0,049).

Conclusão: Gênerofemininoetempodeintubac¸ãoprolongadotiveramassociac¸ão signi-ficativacomdorabdominalduranteacolonoscopia.Pacientescomdesconfortotiveram umataxamaiordeinsucessonoexame.Dosesadicionaisdemidazolamadministradasnos pacientescomdornãoforamefetivas.

creativecommons.org/licenses/by-nc-nd/4.0/).

Introduction

Colonoscopyisthemostaccurateexaminationforthe diagno-sisandfollow-upofcolorectaldiseasessincethisprocedure allowsacompleteevaluationofmucosaeofthewholelarge intestineand distal terminalileum.1 _In_order _to_obtain _an

effective,goodqualityexamination,whatisneededistocount onanexperiencedendoscopist,anadequatepreparationof thecolon,andpatientcooperationundereffectiveanalgesia andsedation.2–4

Inordertoperformtheendoscopicprocedure,thepatient issubmittedtoamoderatesedationofthe“conscious”type, inwhich the condition ofa responseto verbal and tactile stimulipersists,andthecardiovascularandrespiratory sys-temsremainwiththeirspontaneousfunctions.5,6_Among_the

characteristics of sedation during colonoscopy, those with animmediateeffectstandout;sedationshouldlastjustthe time of examination and the procedure should provide a rapidrecoveryofthepatient,causinglittleornosideeffect.6

In view of these premises, benzodiazepine agents (which reduce anxiety and sedate the patient) are routinely used in association with opioids (responsible for analgesia dur-ingtheexamination).7_In_addition,_conscious_sedation _with

benzodiazepinesandopioidsisalower-costalternativewhen comparedtointravenoussedationperformedwithpropofol, ahypnoticagentwidelyusedtoperformendoscopic proce-dures.Thisdrugpromotesdeepsedationandbringsagreater riskofsideeffects,forexample,respiratorydepression.8

Several factors are related to the greater probability of occurrenceofpainduringcolonoscopy;suchfactorsmaybe intrinsictothepatientormaybeofanexternalorder.Some ofthesefactorsare:veryyoungoradvancedage,female gen-der,lowbodymassindex(BMI),previousabdominalorpelvic surgery,poorcolonic preparation,insufficientsedation,the formationofloops,and highpressure ofthe airinflated to promotecolonicdistension.9

Theaimofthisstudywastoidentifyfactorsrelatedtothe patientandtotheexaminationthatcouldbeassociatedwith theoccurrenceofabdominalpainduringcolonoscopy,aswell

asanevaluationofthelevelofpainpresentedbythepatients andtheefficacyofconscioussedation.

Methods

The present study,of the observationaltype witha cross-sectional design, was approved by the Research Ethics CommitteeoftheUniversidadedoSuldeSantaCatarinaunder opinion875.131,CAAE36089414.5.0000.5369,accordingtothe normsoftheConselhoNacionaldeSaúdeforresearch involv-inghumanbeings,resolution466/2012.

Patients who underwent elective colonoscopy between February 2014 and February 2015 by the Endoscopy and ColonoscopyServiceofaprivatepolyclinicfromacityinthe SouthofBrazil,whichattendsprivatehealthplansand con-sultations,wereevaluated.ThestudystartedinFebruary2015 andendedinNovember2015.

All patients who were attended on an outpatientbasis andwhounderwentcolonoscopywereincludedinthisstudy. Patients who needed an emergency examination or who underwentdeepsedationwereexcludedfromthestudy.

Allpatientsreceivedano-residuedietthedaybeforethe test,followedbya12-hourfast.Onthedayofcolonoscopy, colonicpreparationwasperformedwithabalancedsolution ofpolyethyleneglycol,1000mLPO,4hbeforethetest,in com-binationwiththeantiemeticagentondansetron,8mgPO.

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MILD MODERATE SEVERE

VISUAL ANALOG SCALE (VAS)

0 1 2 3 4 5 6 7 8 9 10

Fig.1–VisualAnalogScale(VAS)forpain.

ofexperience.EndoscopesPentax® EPK1000serieswereused forthecolonoscopicprocedures.

Thefollowingdatawerecollectedbycompletinga Medi-calRecordsCard:age,gender,weight,height,BMI,indication ofcolonoscopy(diagnosticortherapeutic)andclinical indi-cation (which was the disease to be investigated and/or treated),theoccurrenceofapreviouspelvicsurgeryand/or prior colonoscopy, duration of examination (timed by the colonoscopydevice itself),anappropriate(withoutstool,or withaminimum ofsolidstoolsand presentingonlysmall amountsofclearliquidrequiringsuction)orinadequate (pres-enceofsolidorsemi-solidintestinalcontentsnoteffectively eliminated) preparation of the colon,10 _a _complete _or _an

incompleteexamination,theadministereddoseoffentanyl andmidazolam,andthedegreeofabdominalpaininformed (0:nopain,1–2:mildpain[welltolerated],3–7:moderatepain [bearable],or8–10:severepain[theworstpainpossible]),11_as

measuredbytheVisualAnalogScale(VAS)forpain12₍_Fig.₁_).

VASwasappliedaftertheprocedurewasperformed,butonly whenthepatientshowedacompleterecoveryof conscious-ness.Thepatientwasthendischarged.

Forthisstudy,theFreeandInformedConsentTermwasnot obtained;onlyoneJustificationfornotusingthisdocument incasesofresearchcarriedoutbasedontheuseofclinical recordswasperformed.

ThedatawererecordedinaspreadsheetoftheEpiInfo® Program version 3.5.4and analyzedin the programSPSS® version20.0.Weadoptedasignificancelevellowerthan5% (p<0.05).Thevariablesweredescribedusingmean/standard deviationfornumericalvariables,andusingrelativefrequency forcategoricalvariables.Fortheassociationofcategorical vari-ablestheChi-squaredtestwasused;forthecomparisonof meanstheStudent’st-testwasused;andforthecorrelation ofvariablestheSpearmanCorrelationCoefficientwasapplied, withRho()between−1and+1.

Results

Ofthetotalof957patientsevaluated,566werewomen(59.1%) and391(40.9%)weremen,withameanageof54.81(20–87) years.ThemeanBMIforthesepatientswas27,064(14.5–45.4).

Table1liststhecharacteristicsofpatientsintermsof

gen-der, age, BMI, number (%) ofpatients who had previously undergoneacolonoscopy,numberofthosewhohadan appro-priatecolonpreparation,andthenumberofpatientswhohad acompleteexamination.

Table2liststhe indicationspresentedbythosepatients

seenforthecolonoscopy.

Table1–Generalaspectsofpatientsundergoing colonoscopyunderconscioussedation.

Characteristics Number(%)

Gender

Female 566(59.1)

Male 391(40.9)

Age(mean)

<54.81years 409(42.7)

≥54.81years 548(57.3)

BMI

<18.5 12(1.3)

≥18.5<25.0 319(33.3)

≥25.0<30.0 395(41.3)

≥30.0 231(24.1)

Previouscolonoscopy

Yes 216(22.6)

No 741(77.4)

Preparationofcolon

Suitable 941(98.3)

Inapporpriate 16(1.7)

Completeexamination

Yes 918(95.9)

No 39(4.1)

Table2–Indicationsforperformingcolonoscopyunder conscioussedation.

Indication Frequency(%)

Abdominalpain 268(28)

Intestinalbleeding 191(20) Changeinbowelhabits 141(14.7)

Monitoring 132(13.8)

Familyhistoryofcolorectalcancer/polyposis 46(4.8) Indicationnotmentioned 33(3.4)

Anemia 31(3.2)

Inflammatoryboweldisease 30(3.1) Oncologicalfollow-up 28(2.9) Post-polypectomyfollow-up 24(2.5)

Weightloss 13(1.4)

Proctalgia/tenesmus 11(1.1)

Endometriosis 03(0.3)

Pre/Post-operative 02(0.2) AlterationofCEAlevela ₀₂_(0.2)

Portalhypertension 01(0.1) Alterationofdigitalrectalexam 01(0.1) Total 957(100)

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Table3–Abdominalpainlevelaccordingtothegender ofthepatientundergoingcolonoscopyunderconscious sedation.

Mildpain Moderatepain Intensepain p-Value

Gender

Female 21(3.7%) 31(5.5%) 15(2.6%) 0.011 Male 08(2%) 11(2.8%) 03(0.8%)

Amongthe957patients,868(90.7%)didnotpresent abdom-inalpain,while89(9.3%)reportedsomelevelofpainduringthe examination:29(3.0%)classifiedtheirpainasmild,42(4.4%) asmoderate,and18(1.9%)assevere.Themeanageofpatients withoutabdominalcomplaintswas54.99years,andthemean numberofpatientswithdiscomfortwas53.06years(p=0.216).

ThemeanBMIofpatientswithoutandwithpainwas27,025

and27,450,respectively(p=0.380).

Regarding gender, men presented greater tolerance to

colonoscopyversuswomen.Ofthe391malepatients,22(5.6%)

had some abdominal complaints regarding the procedure.

Amongthe566womensubmittedtocolonoscopy,painwas

recordedby67(11.8%)patients(p=0.011).Table3presentsthe abdominalpainlevels,accordingtogender.

Among the 273 patients with some type of abdominal surgery,29(10.6%)reportedpainand60(8.8%)ofthe684 indi-vidualswhohadneverundergoneabdominalsurgerysuffered discomfortduringtheexamination(p=0.485).Amongthe394 individualswithapreviouspelvicsurgery,45(11.4%)showed intolerancetocolonoscopy.Ofthe563patientswithoutprior pelvicsurgery,44(7.8%)showedabdominalpain(p=0.270).

Regarding a previous colonoscopy, of the total of 216 patientswhohadpreviouslyperformedanexamination,19 (8.8%)showedsomeintoleranceduringtheirlastcolonoscopy.

Amongpatientswhounderwentcolonoscopyforthefirsttime, 70(9.4%)complainedofpain(p=0.340).

Ofthetotalof935patientsdiagnosedforcolonoscopy,86 (9.2%)reportedsomelevelofpain.Amongthe22patientswith atherapeuticindication,3(13.5%)reportedpain.

Ofthe 941individualswithan appropriatecolon prepa-ration, 87 (9.2%) reported some complaint during the examination.Ontheotherhand,amongthe16patientswho didnothaveagoodpreparationofthegastrointestinaltract, only2(12.5%)reportedpain(p=0.354).

Ofthetotalnumberofpatientsanalyzed,918underwenta completeexamination,81(8.8%)ofwhomwereintolerantto colonoscopy.Amongthe39patientswhocouldnotcomplete theexamination,8reporteddiscomfort(p=0.049).

Table4describesthepainlevelsfound,accordingtothe

variablesevaluatedbythestudy.

The mean duration ofcolonoscopy in patients without abdominalcomplaintswas10.57minandthemeannumber ofpatientswithabdominalpainwas12.26min(p=0.001).We observedthatthelongertheinsertiontimeofthecolonoscopy device (which corresponds to the time elapsed from the introduction of the device toits arrival inthe cecum), the higherthepatients’painlevel(p=0.036).Inwomenthe intu-bation time was longer, with a mean time of 11.18min, while in men the mean intubation time was 10.38min (p=0.001).

Regardingmedications,170patientsreceivedextradoses of midazolam, in accordance with the abdominal com-plaintsreportedduringtheexamination.Themeandoseof midazolam administered to patients with discomfort was 5.67mg,alevelhigherthanthemeandoseadministeredto patientswithoutcomplaints,whichwas5.16mg(p<0.001*). The mean dose of fentanyl given both in patients who reportednopainandinthosewhoreportedpainwas0.05mg (p=0.716).

Table4–Abdominalpainlevelofpatientsundergoingcolonoscopyunderconscioussedationaccordingtothestudy variablesevaluated.

Nopain Mildpain Moderatepain Intensepain p-Value

Abdominalsurgery 0.485

Yes 244(89.4%) 8(2.9%) 13(4.8%) 8(2.9%)

No 624(91.2%) 21(3.1%) 29(4.2%) 10(1.5%)

Pelvicsurgery 0.270

Yes 349(88.6%) 15(3.8%) 20(5.1%) 10(2.5%)

No 519(92.2%) 14(2.5%) 22(3.9%) 8(1.4%)

Previouscolonoscopy 0.340

Yes 197(91.2%) 3(1.4%) 12(5.6%) 4(1.8%)

No 671(90.6%) 26(3.5%) 30(4%) 14(1.9%)

Indication 0.785

Diagnostic 849(90.8%) 21(3%) 48(4.4%) 17(1.8%)

Therapeutic 19(86.4%) 1(4.5%) 1(4.5%) 1(4.5%)

Preparationofcolon 0.354

Suitable 854(90.8%) 29(3.1%) 40(4.2%) 18(1.9%)

Inappropriate 14(87.5%) 0(0%) 2(12.5%) 0(0%)

Completeexamination 0.049

Yes 837(91.2%) 27(2.9%) 37(4.0%) 17(1.9%)

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Discussion

Colonoscopyisthemostaccuratediagnostictoolforcolorectal diseases;however,inaconsiderablenumberofsituationsit canbeanuncomfortableprocedureforthepatient,andthisis oneofthemaincausesofresistancetothisprocedure.

Manyofthefactorsthatcontributetoabdominal discom-fortduringcolonoscopyhavealreadybeenidentifiedandcan bemanagedinordertoincreasethepatient’stolerancetothe examination.Appropriateguidelinesontheprocedure,a cor-rectpreparationofthecolon,andagoodsedation/analgesia forthereductionofanxiety,aswellastheadoptionof estab-lishedtechniquesduringtheexamination(suchaschanging thepatient’spositionandtheuseofmanualabdominal com-pression)arekeymeasuresforobtainingalessuncomfortable colonoscopy.However,somefactorswidelydescribedinthe literatureareinherenttothepatientandcannotbemodified, suchasanatomy,gender,age,BMI,andpreviousclinicaland surgicalhistory.9

There iscurrently no standardizedmethod for evaluat-ingabdominalpainduringcolonoscopy.Inthepresentstudy, wechose touse VAS12 _because _this _is_a _procedure _that _is

easytoapplyandunderstand,especiallyafterrecoveryfrom sedation.VASrangesfromzeroto10,wherezeromeansno pain,1–2equalsmildpain,3–7suggestsmoderatepain,and valuesbetween8and10correspondtoseverepain.This eval-uationisalsoaccompaniedbyvisualresources, withfacial expressionsthatillustratepainintensity.However,VASisa one-dimensional method, whichevaluates the intensity of painonlyatagivenmoment,withouttakingintoaccountany otheraspect.12

The present study showed that, despite all the factors thatmaycontributetoabdominalpainduringcolonoscopy, 868(90.7%)ofthose957patientstreatedtoleratedverywell the examination, without presenting any abdominal com-plaints.Regardingthosepatientswhoreporteddiscomfort,it wasobservedthatwomenshowedhigherlevelsofabdominal pain,withalongertimeofintubationofthecolon.Regarding the technique, prolonged intubationtimes are also associ-atedwithhigherlevelsofpainduringcolonoscopy.Itwasalso observedthatinpatientswhoreportedabdominalcomplaints, thetotaldoseofmidazolamadministeredwasgreaterthan thedoseadministeredinpatientswhodidnotcomplain.The percentageofincompleteexamswasalsohigherinpatients whoreportedpain.

Inthisstudy,theassociationbetweenfemalegenderand abdominalpainwaspositively significant.Ofthe 67(11.8%) womenwhoreportedpain,21describedtheepisodeasmild, 31asmoderate,and15assevere.Inanumberofpublished studies,13–15 _female _gender _has _already _been _identified _as

anindependentriskfactorassociatedwithabdominalpain duringa colonoscopyprocedure. In addition tohigher lev-elsofdiscomfort,generallyinwomentheintubationtimes arelonger and thepercentageofincompleteexams isalso higher. This is because the female colon, especially the transversecolon, ismoreelongated;besides,its abdominal musculatureisweaker.Thissituationisapredisposingfactor for the formation of loops in the endoscope, which ham-perstheexamination.16,17_Although_this_relationship_was_not

detected in the present study, the female patients’ surgi-calhistory showedastrong relationshipwiththepresence of abdominal pain in previous studies.18,19 _The _procedure

ofcolonoscopyisalsohamperedbytheformationofbands and adhesions,whicharerelativelycommoncomplications ofabdominopelvic surgeries.In addition,the perceptionof paindiffersbetweengenders.Onestudy20_demonstrated_that

womenhaveadifferentvisceralpainmemoryversusthatof men.Afterthepatientswerestimulatedbyarectaldistension toactivatevisceralpain,womendemonstratedamoreintense neuralresponsetopain,whichwouldexplainthemoresevere abdominalpaininfemalesubjects.

Theinsertiontimeofthecolonoscopewasautomatically timedbythedeviceused.Theevaluatedservicehasadopted this practicefor morethan 10years,and this variable has been routinely recorded in the patient’ medical record, in ordertoobtainabettercontroloftheintubationtime,since the prolongedinsertiontime ofthe devicealsocontributes toabdominaldiscomfort.17_The_complete_examination_begins

with theinsertion ofthedevice throughthe anus,passing through the rectum, sigmoid,descending colon, transverse colon,andascendingcolonuntilitreachesthececum.2_In_the

presentstudy,themeantimeofintubationofpatientswho reportedpainwas12.26min,i.e.1.29minlongerthanthemean intubationtimeforpatientswithoutabdominalcomplaints. Thepainlevelofthepatientsanalyzedwasdirectly propor-tionaltothetimeofintubationofthecolon:thelongerthe intubationtime,themoreseverethepainreported.Inthose womenwhoparticipatedinthepresentstudy,intubationtime waslonger(mean:11.18min),whileinmenthemean intuba-tiontimewas10.38min.Thisresultissimilartothatofastudy conductedinXijing,China,21_in_which_technical_difficulty,

pro-longedintubationtime,andconsequentlythepainlevelwere higherinfemalepatients.

A colonoscopycould be performed without any typeof analgesia;but becausethis isaninvasiveexaminationand alsobecauseoftheanxietyandfearofpainshownbymany patients,mostEndoscopyServicesusesomekindofconscious sedationthroughtheassociationofbenzodiazepinesand opi-oids. Midazolam isa benzodiazepine agentthat decreases anxietyandcausessedationofthepatient;ontheotherhand, fentanylisashort-actingopioidagent,responsiblefor anal-gesiaduringtheexamination.Theactionofthesetwodrugs beginsabout2minaftertheirintravenousadministrationand thepatient’srecoveryisrapid,7_with_due_respect_to_the

pre-ceptsofconscioussedation.Weobservedthat170patients received extra doses of midazolam in addition to the ini-tial doseand thatthe mean doseadministered inpatients who experienced pain was significantly higher versus the doseadministeredinpatientswithoutcomplaints.Whilethe groupwhoreportedabdominalpainreceivedameandoseof midazolamof5.67mg,patientswithoutcomplaintsreceived ameandoseof5.16mg.Inmostofthesepatients,thetypeof paindescribedwasofthemoderatetype,whichshowsthat, evenwiththerecommendedsedationandanalgesia,the med-icationisoftenineffective.Astudy14_also_demonstrated_the

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psychologicalprofileofthepatientshouldbepreviously inves-tigated.Inpatientswithariskfactorfordiscomfortduring colonoscopy,forexample,femalegender, anxiouspatients, and patients with low BMI, the sedation could be more intense.

Aslimitationsofthepresentstudy,wecanhighlightthe absenceofevaluationofthepatient’s socialconditionsand theiranxiouscomponentandcomorbidities,besidesthe med-ications used bythe study participants – factors that may influencetheperceptionofpain,increasingordecreasingits threshold.Themethodchosenfortheevaluationofabdominal painmeasuresonlyitsintensity,withouttakingintoaccount othercharacteristics.Anotherlimitationofthestudyislinked tothefactthatcolonoscopieswereperformedbymorethan oneprofessional;therefore,differencesintheprocedureand inthedescriptionofdatainthepatients’medicalrecordmay havebeengenerated.ThetimeofapplicationofVAS,12_even

afterthefullrecoveryofconsciousnessbythepatient,may havecausedamemorybiasinsomeparticipants,considering thatoneofthepossiblesideeffectsofmidazolamisamnesia.7

Becausethisisacross-sectionalstudy,it isnotpossibleto determinethecausalityoftheresults.

Conclusion

Colonoscopywasawell-toleratedprocedurewhenperformed underconscious sedation,because despitethe several fac-torsthatcontributetotheappearanceofabdominalpain,in the current study the number of patients with discomfort was low: only 9.3% of the total of 957 individuals evalu-ated reported pain. Of the total number of patients with abdominalpainduringtheexamination,3.0%reportedmild pain,4.4%hadmoderatepain,andonly1.9%reportedsevere pain – data confirming that, despite being uncomfortable, colonoscopy is a well-tolerated examination. A significant associationbetweenfemalegenderandprolongedintubation timeversusabdominalpainduringcolonoscopywasfound, alsowithsignificancebetweenthesetwovariables.In rela-tiontosedationandanalgesiaofthepatients,itwaspossible toperceivethatthe associationoffentanylandmidazolam promoted an adequate effect; however, the administration ofsafe extradosesofmidazolaminpatients whoreported painduringtheexaminationwasnoteffectiveinimproving pain.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

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