J. Coloproctol. (Rio J.) vol.35 número1

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

Journal

of

Coloproctology

Original

Article

Manometric

analysis

of

the

influence

of

rectal

content

on

anal

pressures

in

chronically

constipated

patients

Rodrigo

Ciotola

Bruno

,

Fang

Chia

Bin

,

Maria

Auxiliadora

Prolungatti

César

,

Wilmar

Artur

Klug

_,

_Sylvia

_Heloisa

_Arantes

_Cruz

a_{FaculdadedeCiênciasMédicasdaSantaCasaSãoPaulo(FCMSCSP),SãoPaulo,SP,Brazil}

b_{DepartmentofMedicine,UniversidadedeTaubaté(UNITAU),Taubaté,SP,Brazil}

a

r

t

i

c

l

e

i

n

f

o

Articlehistory:

Received8October2014 Accepted2February2015 Availableonline2February2015

Keywords: Constipation Manometry Rectaldiseases

a

b

s

t

r

a

c

t

Objective:Theaimofourstudywastoanalyzewhetherthepresenceofcontentinthe rec-tuminfluencestheanorectalmanometryexaminationresultsinchronicallyconstipated patients.

Methods:Weevaluated38chronicallyconstipatedpatients,36womenand2men,withan averageageof53.55yearsofage,allwithascoreabove10ontheAgachanConstipation ScoringSystem.Allthepatientsunderwentrectalpreparationandthenhadtheanorectal manometryexaminationwithoutrectalcontentandafter5minhaditwitharectalballoon inflatedwith200mlofairintherectum.

Statisticalanalysis:Thestatisticalparametricpaired-ttestwasappliedinordertoverifythe differenceinresponsebetweenthegroupsafteranintervention,adoptingasignificantlevel of5%(p<0.05).

Results:Theanalpressurewasanalyzedfromthestandardanalmanometryexamination andwefoundastatisticallysignificantinfluenceonthemanometricresultsforthepatients’ averagerestingpressures,absoluteaveragecontractions,averagecontractions,evacuations, andsustainedcontractionsinthefunctionalanalcanals.

Conclusion:Thepresenceofrectalcontentinfluencesthemanometricvaluesofaverage res-tingpressure,averageabsolutecontraction,averagecontraction,evacuation,andaverage sustainedcontractionsinthefunctionalanalcanalinthegroupofchronicallyconstipated patients.

©2015SociedadeBrasileiradeColoproctologia.PublishedbyElsevierEditoraLtda.All rightsreserved.

∗ _{Correspondingauthor.}

E-mail:[email protected](R.C.Bruno). http://dx.doi.org/10.1016/j.jcol.2015.01.004

Análise

Manométrica

da

Influência

do

Conteúdo

Retal

nas

Pressões

Anais

em

Pacientes

Cronicamente

Constipados

Palavraschave: Constipac¸ão Manometria Doenc¸asRetais

r

e

s

u

m

o

Objetivo: Oobjetivodesteestudofoianalisarseapresenc¸adeconteúdonoretoinfluencia osresultadosdoexamedemanometriaanorretalempacientescronicamenteconstipados. Métodos: Foram avaliados38 pacientescronicamente constipados, 36 mulherese dois homens,commédiade53,55anosdeidade,todoscompontuac¸ãoacimade10noAgachan ConstipationScoringSystem.Todosospacientesforamsubmetidosapreparoretale,em

seguida,passaramporumexamedemanometriaanorretalsemconteúdoretale,depois

detranscorridoscincominutos,umnovoexamefoirealizado,agoracomumbalãoretal infladocom200mldearnoreto.

Análiseestatística: Naanáliseestatística,foiaplicadootestetparamétrico,comafinalidade deverificaradiferenc¸a,emtermosderesposta,entreosgruposapósumaintervenc¸ão.Para tanto,foiadotadoumníveldesignificânciade5%(P<0,05).

Resultados: Apressãoanalfoianalisadacombasenoexamedemanometriaanalderotina; emnossospacientes,foiobservadainfluênciaestatisticamentesignificativanos

resulta-dos manométricosparaas pressõesmédiasem repouso,contrac¸õesmédiasabsolutas,

contrac¸õesmédias,evacuac¸õesecontrac¸õessustentadasnoscanaisanaisfuncionais. Conclusão: Apresenc¸adeconteúdoretalinfluenciaosvaloresmanométricosdapressão médiaemrepouso,contrac¸ãoabsolutamédia,contrac¸ãomédia,evacuac¸ão,econtrac¸ões sustentadasmédiasnocanalanalfuncionalnogrupodepacientescronicamente constipa-dos.

©2015SociedadeBrasileiradeColoproctologia.PublicadoporElsevierEditoraLtda. Todososdireitosreservados.

Introduction

Changesinbowelmovements,suchasconstipationandfecal

incontinence,are someofthemostcommon

gastrointesti-naldisordersinthegeneralpopulation,ranginginAmerican adultsfrom15%1_to20%.2,3_{Amongthem,constipationismost} prevalent,andcanaffectupto27%ofAmericans.3–5_Thehigh frequencyofthisdisorder,anditshighcost,justifythe impor-tancegiventotheproblem.

From a clinical standpoint, constipationis defined as a

bowelalteration basedonunsatisfactoryevacuation, andit

maybeassociatedwithaninfrequentbowelmovement,

diffi-cultyinpassingstool,orboth.6,7

TheRome III criteria definedfunctional constipation as

occurrenceof2ormoresymptomsforatleast12weeksinthe

absenceofstructuralexplanation.Thesymptomsare

unspe-cific self-reported symptoms, stool frequency of less than

threebowel movementsperweek,guttransittimeofmore

than68h,analblockage,manualmaneuverstodefecate,loose

stoolsareararely presentwithout the use oflaxatives and

thereareinsufficientcriteriaforirritableboweldisease.8–11

In order to classify the prevalence and severity of the

constipation,theAgachanConstipationScoringSystemwas

used.12

Complete evaluationof chronically constipatedpatients

shouldbebasedonamedicalhistoryanddirectedphysical

examination,13_{andinthemostseverecasessupplemented}

withspecificanorectalphysiologyexaminations.11,14

Anorec-tal manometry is considered to be the most important

of these examinations and provides detailed information

on the motor and sensory activities in the region being

studied.4,5,15–18

International gastroenterology and coloproctology

soci-etieshavestandardizedthemethodologyandinterpretation

ofthisanorectalmanometryexamination.15

Thus,consideringtheimportanceofthisexaminationand

reviewingthemedicalliteratureonanorectalmanometryin

chronicallyconstipatedpatients,thereremainsthequestion

ofwhetherthepresenceofcontentintherectuminfluences,

ornot,theexaminationresults.

Cleaning of the rectum before manometry is especially

importantinchronicallyconstipatedpatients,asthepresence

oflargeamounts offecesinthe rectummay influencethe

positioningofthecatheter.18_{Irrespectiveofthesehypotheses,}

anorectalphysiologyservicesignorethisandperformrectal

examinationswithoutrectalpreparation,11,19–22_whileothers emptytherectalampullabeforetheexamination.2,5,18

Given this, and not having found in the literature any

clearreferencestotheimportanceorotherwiseofpre-existing

content in the rectum or prior preparation for anorectal

manometry, we came up with this comparative study, in

which weevaluatedthe examinationinquestionwith and

withoutrectalcontentinchronicallyconstipatedpatients.To

simulate thepresenceofcontent intherectum duringthe

examination,weinsertedaninflatedrectalcatheterballoon

and compared it with the data obtained with the balloon

deflated.

Theobjectiveofthispaper,then,istoanalyzewhetherthe

presenceofknowncontentintroducedtotherectalampulla

influencestheanorectalmanometryexaminationresultsin

Material

Weevaluatedthedataobtainedfromtheanorectal

manom-etryexaminationscarriedouton38chronicallyconstipated

patientsatthe ColoproctologyClinicattheUniversity Hos-pitalatTaubatéUniversity(UNITAU)fromJuly2010toApril 2011.

Method

Thisisaprospectivestudywithchronicallyconstipatedadult

patients at the Coloproctology Clinic, at UNITAU

Univer-sityHospital.AllofthepatientsmettheRome III23_criteria

and scored above 10 onthe Agachan Constipation Scoring

System.12_{Thepatientssignedaninformedconsentformand}

thestudywasapprovedbytheEthicsCommitteeUniversity

HospitalatTaubatéUniversity(UNITAU).

We excluded patients with anorectal diseases known

to lead to impairment in anorectal manometry values,

suchasgradeIVhemorrhoids,analfissures,and fistulas.24

Associated with these, we also excluded patients who

had had anorectal surgery, abdominal pain concomitant

withamanometryexamination,organic diseasediscovered

throughcolonoscopy,patientswithirritablebowelsyndrome,

megacolon,24 _{those who used oral antihypertensive drugs}

basedoncalciumchannelblockers,11_{andpatientswhohad}

notbeensuccessfullyrectallyprepared.

All 38 patients underwent the anorectal manometry

examinationhavingpreviouslybeen rectallyprepared. The

preparationwascarriedoutwithasorbitol-basedstimulant

andsodiumlaurylsulphate,applyinga5mlvialrectallythe daybeforeandtwovials2hbeforetheexamination.

Eachexaminationwasconductedintwophases:thefirst

phasewiththerectalballoondeflated,andsoonafter, with-outremovingthecatheterfromtheanorectalregion.Thefirst

phasewascalledgroup1.Theexaminationwasrepeated,but

thistimewiththerectalballooninflatedintherectalampulla, simulatingfecalcontentintherectum.Thesecondphasewas calledgroup2.

Nodigitalrectalexaminationwascarriedoutinadvance,

soasnottocompromisethetoneoftheanalsphincters.

Thestudywasbasedonthestandardanorectal

manom-etry examination, measuring pressure at rest, contraction,

absolute contraction, evacuation, maintained contraction,

sustentioncapacity, andfatiguerate forthe anal sphincter

muscles,centimeterbycentimeter,from5cmfromtherectum (Fig.1).Followingthisstep,rectalsensitivitywasanalyzedby measuringtheanalinhibitoryreflex,thelowestsensitive vol-umeintherectum,andthevolumeforthedesireforconstant

evacuation.Themaximumrectalcapacitywasnotanalyzed,

inordernottocompromisethenextphaseoftheexamination.

Attheendofthisphase,thecatheterballoonwasslowly

inflatedintherectalampulla,approximately 5cmfromthe

analverge,with200mlofair,tofilltheentirerectalampulla andthussimulatearectumwithcontent(Fig.1).5,25_Wewaited forapproximately5min5_{fortherectalandsphinctermuscles} tosettle.Thecatheterwasthenwithdrawn,andallthe

mea-surementswerecomparedwiththosetakenwithadeflated

balloon.

Statistical

analysis

The statistical analysis evaluated possible differences

between the data obtained in anorectal manometry

per-formedinchronicallyconstipatedpatientswithandwithout

rectalcontent.

Forthispurpose,thestatisticalparametricpaired-ttestwas appliedinordertoverifythedifferenceinresponsebetween thegroupsafteraninterventionadoptingasignificantlevel of5%(p<0.05).Theanalysiswasperformedwiththesoftware SPSSStatisticsversion22.

Results

Inthisstudy,outof38patients,36(94.7%)werefemaleand

onlytwo(5.3%)weremale. Theaverageageofthepatients

was53.55yearsold,themainagegroupbeingthatbetween

thefifthandsixthdecadesoflife,accountingfor65.78%ofthe sample.

Thesamplescoredanaverageof17.66outofamaximumof

30ontheAgachanConstipationScoringSystem,illustratinga highlevelofconstipationforthegroupaverage.Inthissame

sample,21patients(55.26%)hadsevereconstipation,witha

scoreofmorethan18points.

Withregardtothetimeofonsetofthesymptomstodate,11 patients(28.9%)hadanaveragetimeof5–10years;13patients (34.2%)from10to20years;9patients(23.7%)hadmorethan

20 years,and onlyfive ofthe 38 patients(13.2%)had been

constipatedforaperiodof1–5years.

Theaveragelengthofthepatients’functionalanalcanal

was2.42cm,whichisinlinewiththeanatomicalstandard,

with94.7%ofthesepatientsbeingfemale.

Intherectalsensitivitytest,thesmallestsensitivevolume intherectumwasanaverageof33.29ml,andinitialvolumefor thedesireforconstantevacuationwasanaverageof53.29ml ofHg.

Theanorectalpressuresanalyzedinthemanometry

exam-inationsinbothgrouponeandgrouptwoarecomparedbelow,

showinganimportantandstatisticallysignificantdifference betweenthepressuresatrest,contraction,absolute contrac-tion,evacuation,andsustainedcontraction.Neithertherate

offatiguenorthecontractionsustentioncapacityshoweda

statisticallysignificantdifference.

The following Table 1 compares the average resting

pressures, the absolute contraction pressure, contraction

pressuresaverageandaverageevacuationpressurefor3cm

fromtheanalcanal.

Table2comparestheaveragesustainedcontraction pres-sureinthefunctionalanalcanalsofchronicallyconstipated patientsingroups1(rectalballoondeflated)and2(rectal bal-looninflated),obtainingstatisticallysignificantresults.

Discussion

Anorectal manometry is part of the study protocol for

Fig.1–Simulationofanorectalmanometryexaminationwithandwithouttherectalballoondeflated.

Table1–Comparisonwiththepressuresfoundduringanorectalmanometryfrom3cmoftheanalcanalinchronically constipatedpatientsingroups1and2fromJuly2010toApril2011.

Groups Average

resting

Standard deviation

Absolute contraction

Standard deviation

Average contraction

Standard deviation

Evacuation Standard deviation

1 52.98 26.7 12.528 60.01 73.82 49.33 64.52 30.60

2 40.17 25.21 96.71 54.61 57.98 39.55 44.33 26.04

p=0.001 p<0.001 p<0.001 p<0.001

Source:ColoproctologyClinic–UNITAUUniversityHospital.

additiontotherebeingagreatdealofnon-comparable equip-mentandcriteriaintermsofmethodology.

There is also disagreement over whether or not there

shouldbepriorpreparationandwhetherornottherectal con-tentcaninfluenceresults.SeveralBrazilianandinternational

serviceshaveperformedanorectalmanometryexaminations

andpostedtheirresultsinextensivestudies,butwithoutthere beingany standardizationregardingrectal preparationand theimportanceoftheexistenceorotherwiseofsolidorother fecalwasteintherectum.

Klugetal.,27,28_{inhisstudiesattheFacultyofMedical} Sci-encesatSantaCasainSãoPaulo,andCaesaretal.,11,20,21_at

theDepartment ofMedicine,University ofTaubaté, donot

routinelycarryoutrectalpreparationbeforetheexamination. However,theworkpublishedbyauthorssuchasRaoetal.,5,25

Raza and Bielefeldt,2 _{Pfeifer et al.}24 _{and Oliveira}24

recom-mendsrectalpreparationinpatientspriortocompletionof

amanometrytestasroutine.

Rao et al. intheir work perform a500ml rectal enema

30minbeforetheexamination.5,25 _{RazaandBielefeldt,}

how-ever,recommendedcleaningwithanenemaonthemorning

oftheexamination,alsoinordertoemptytherectalampulla.2

These authors believe that in chronically constipated

patients,notcleaningtherectalampullamayinfluencethe

positioningofthecatheter,influencingtheacquisitionofdata,

aswellasobstructingthechannels,compromisingthe

exam-inationresults,24 _{thisbeingoneofthereasonstoclean the} rectum.

However,basedonthesedifferentstudies,theneedarose

todefinetheimportanceofcontentintherectum,whichcould

Table2–Comparisonbetweentheaveragessustainedcontractionpressureinthefunctionalanalcanalsofchronically constipatedpatientsingroups1and2fromJuly2010toApril2011.

Groups Numberof

patients

Minimum Maximum Average Standard

deviation

1 38 24.7 163 93.02 33.14

2 38 4.3 138.4 72.51 35.32

p<0.001

possiblyaltertheresultsofmanometrytestsandother exam-inations.Ifthecontentpresentintherectumofchronically constipatedpatientsdoesinterferewithanorectalmanometry results,besidestheneedtoestablishapreparationstandard,

then there is a need to more carefully interpret some of

theresultsobtainedand,furthermore,understandhowthese

functionaldisorderswork.

AuthorssuchasRazaand Bielefeldt andRaoand Singh

performdigitalrectalexaminationspriortointroducingthe manometrycatheter.2_Klugetal.27,28 _{andCesaretal.,}11,19–22

onthe other hand, donotbelieve thatthis dilation ofthe

sphinctermusclescouldcompromisetheexamination.

Thesampleof38patientsstudiedhereinhadamoderate

toseveredegreeofconstipation,accordingtothescoring

sys-temrecommendedbyAgachan.12_{Theminimumscorewas12}

points,andthemaximumwas24points,withanaverageof

17.66,inarangefrom0to30.

In our study, the symptoms of constipation had been

present in75% ofthe patients formorethan 5years,and

in34.2%(13patients)theyhadbeenpresentfor10–20years,

with23.7%havingthemforover20years.Thesefigures

cor-roboratetheepidemiologicalconcernsheldbysomeBrazilian

andinternationalauthors,29,30_{whostressonlargesizeofthe} groupaffectedbythisdisorderandthepsychological,social, andeconomicproblemsitcausesinoursocietyasawhole.

Thedataonrectalsensitivityanalyzedwerethefirst

sen-sation and the desireforconstant evacuation. The results

obtainedforthe lower sensitivevolume inthe rectum, on

inflatingtheballoon,producedvaluescompatiblewiththose describedintheliteratureforchronicallyconstipatedpatients, i.e.greaterthan30mmHg.5,24,31,32

Ineverydayclinicalpractice,themostreliablewayto mea-surerectalsensationisbymanualdistensionwithanair-filled balloon.31_{Thus,basedontheresultsformaximumtolerable}

pressureintherectalampullainanorectalmanometry

sen-sitivitytestsfoundintheliterature,theballoonwasinflated with200mlofairtoperformthemanometrytestwithrectal content.2,5,24,28 _{Thisissufficientvolumetoshapetherectal}

ampulla,stimulatingsensitivityandsimulatingthepresence

ofcontentintherectum,asoccursinchronicconstipation,

whencarryingouttheexaminationunprepared.31

Scottetal.31 _{in2011,whenanalyzingmotordysfunction}

andrectalsensitivityinchronicallyconstipatedpatients,also

demonstrated the highest capacity ofthe rectum in these

patients,callingthemmegarectums(orcompliantrectums).

Thesetwofactors–greatercapacityoftherectalampulla

inthechronicallyconstipated31_{andthemaximumvolumeof}

200mltofeelthedesiretoevacuate–ledustothisvalueforthe performanceoftheanorectalmanometrytestwithaninflated balloon.5

Inourresults, wefoundastatisticallysignificant

differ-ence inthepatients’ functional analcanalsinmostofthe

pressuresanalyzedwhenweconductedtheexaminationwith

andwithoutcontentintherectum.

Toachieveabetteranalysisofthepressures,wethen

com-pared,centimeterbycentimeterintheanorectalcanal,the

averageforthe3cmfromtheanalcanal,andtheaveragesfor thefunctionalanalcanalforeachpatient.

Analyzingtheaveragepressuresforthe3cmfromtheanal canalandtheaveragesofthepressuresforthefunctionalanal

canalatrest,absolutecontraction,contraction,andsustained

contraction fromgroup 1(withtherectal balloondeflated),

weconcludedthattheyare greaterthan thepressures and

average pressures in group2 (rectalballoon inflated), thus

showing,whencomparedwitheachother,statistically signif-icantdifferences.

Comparingcentimeterbycentimeter,therearesomeslight

differencesinthesemeasurementsbuttheydonotinterfere

withthefinalresult.Theratesoffatigueinanalcontraction

andsustentioncapacity,however,showednosignificant

dif-ferenceinanymeasurements.

Grouponeofoursample,with38examinationswiththe

rectalballoondeflated,wasatanaverageof3cmfromtheanal canalandtheaveragerestingpressuresforthefunctionalanal

canal were 52.98mmHgand 59.9mmHg, respectively,

com-paredwith40.17mmHgand48.9mmHgingroup2,withthe

rectalballooninflated.Thesamehappenedwiththeabsolute

pressureofcontractionfortheaverageof3cmfromtheanal

canaland the averageforthefunctional anal canal,which

hadvaluesof125.28mmHgand136.92mmHg,respectivelyin

the groupwiththeballoondeflated,and 114.47mmHgand

96.71mmHgingroup2.

Thefallinpressureincontraction,evacuation,and

sus-tained contraction both in the average forthe 3cm range

and the average for the functional anal canal was clear,

showing the influence that the rectal content has on rest

pressures.

Thefatigueratesand sustentioncapacityvaluesforthe

group withthe rectal balloon deflated compared with the

inflatedballoongroupshowednostatisticallysignificant inter-ferenceforthiscontentonpressures.

Wehave,therefore,demonstratedthatsomeofthe

sphinc-terpressuresmeasuredinanorectalmanometrytestsinthe

chronically constipatedvary depending onthe presenceor

otherwiseofrectalcontent.Thisiscertainlyimportant,given

thewidespreadandlargenumberofpatientswiththis

com-plaintinsocietyanditssocial,economic,andpsychological impacts.

The results found lead us to conclude that there is

a decrease in the average resting pressures in the

func-tional anal canal, in the average pressures for absolute

contraction in the functional anal canal, in the average

pressures forcontraction ofthe functional anal canal, and

in the average pressures for sustained contraction in the

group with examinations carried out with a full rectal

ampulla.

Fortheothervaluesmeasured,suchastherateoffatigue inanalcontractionandthesustentioncapacity,despitethere beingatendencyforthepressurestofall,theresultswerenot statisticallysignificant.

Inconclusion,itispossibletoidentifyanalterationinsome

measurementsofanalpressureinconstipatedpatientswith

intrarectalcontent.Andthepreparationisjustifiedpriorto theexaminationtoavoidsuchinterference.

Conflicts

of

interest

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