Rev. Bras. Anestesiol. vol.65 número5

RevBrasAnestesiol.2015;65(5):421---425

REVISTA

BRASILEIRA

DE

ANESTESIOLOGIA

LETTERS

TO

THE

EDITOR

Letter

to

the

Editor

commenting

the

study

published

in

the

journal

by

Ascedio

Jose

Rodrigues

et

al.

(Rev

Bras

Anestesiol

2013;63(4):358---361),

regarding

flexible

bronchoscopy

intubation

Carta

ao

editor

comentando

estudo

publicado

na

revista

por

Ascedio

Jose

Rodrigues

et

al.

(Rev

Bras

Anestesiol.

2013;63(4):358---361),

a

respeito

de

intubac

¸ão

com

broncoscópio

flexível

DearEditor,

IreadthearticlebyAscedioJoseRodriguesetal.published intheRBA(RevBrasAnestesiol2013;63(4):358---361),andI wouldliketoexposesomeopinionsabouttheawakeflexible bronchoscopyintubation(FBI).

Ashighlightedinthestudy,FBIisnotagoodoptionforthe situation‘‘can’tintubate,can’tventilate’’(CICV),a situa-tionthatinvolvesmajorthreattolife.1_{Fiberopticintubation}

issafe,butrequirestimeandskillandisnotsuitableinCICV situationthatrequiresimmediaterestorationofventilation. Ineverappliedblockade(withneedles)forFBI,andthe reasonisthatifthepatientisabletoopenhismouthenough forintraoralaccesstoperformtheglossopharyngealnerve block,byinjectioninthecaudalportionoftheposterior ton-sillarpillar,thispatientprobablyhasaneasyintubationand doesnotrequireFBI.Moreimportantly,duetotheproximity ofthecarotidartery,thereisapossibilityofintra-arterial injection, or worse, hematoma of the posterior regionof the tongue, which would transform a difficult case in an impossiblecase.

DOIoforiginalarticle:

http://dx.doi.org/10.1016/j.bjane.2012.05.001

Regardingsuperiorlaryngealnerveblock,itisonly feasi-bleinpatientswhodonotneedit;thatis,inleanpatients withwell-definedanatomicallandmarks.Inobesepatients, orpatientsusingcervicalcollarorwithcervicaltrauma,or thosewithshort, thick neck (‘‘taurine’’), preciselythose thatwould benefit fromawake fiberoptic intubation, this blockadeisnolongeragoodoption.

Iperformblockades‘‘withoutneedles’’inmypatients. Inordertoapplylocalanesthetics,Iaskthepatienttopoke histongueandthenIholditwithagauze.On eachside,I applytwopuffsof 10%lidocainein thepalatoglossal arch inanattempttoblocktheglossopharyngealnerveinorder tominimizethegagreflex;followedbyan additionalpuff inthe softpalate. After about 3minutes,I placeagauze soaked in 10% lidocaine in the piriformfossa, behind the baseofthetonguebilaterally.Theobjectiveistoblockthe nervesduetotheirproximitytothemucosasaturatedwith concentratedlocalanestheticsolution.2

Regardingbiteblockapplication,Irecommendusingone of oropharyngeal intubation cannulas. Although there are several on the market, I have available only the VBM® andVAMA®_{(ValentinMadrid).Themaindifferencebetween} themisthatVAMA® _{pushesthesoftpalatebackward,while} VBM pushes the tongue forward.3 _{With the use of these}

tubes,fibroscopyisMUCHeasier(myemphasis):the fiber-scope does not deviate from midline and is directed to theepiglottis, foranestheticsupplementationthroughthe workingchannelof thefiberscope.4_{Withthe useofthese}

cannulasthereis no need todisconnectthe intermediate 22mm device from tracheal cannula.I start with a care-fultitrationofsedativesandadministrationofsupplemental oxygenearlyintheprocedure,inordertomakethe experi-encelessunpleasantforthepatient.

Conflicts

of

interest

Theauthordeclaresnoconflictsofinterest.

References

1.Practiceguidelinesformanagementofthedifficultairway. Anes-thesiology.2003;98.

422 LETTERSTOTHEEDITOR

2.Simmons ST, Scheich AR. Reg Anesth Pain Med. 2002;27(2): 180---92.

3.Gil KSL. Fiber-optic intubation:tips from the ASA Workshop. AnesthesiolNews.2012.

4.Casta˜neda Pascual M, Batllori Gastón M, Unzué Rico P, et al. Comparación de las cánulas VAMA y Berman para la intubación fibroscópica orotraqueal en pacientes anestesiados. Rev Esp Anestesiol Reanim. 2013;60: 134---41.

MarceloSperandioRamos

HospitalUniversitário,UniversidadedeSãoPaulo,São

Paulo,SP,Brazil

E-mails:marcelo.ramos@hu.usp.br,

marcelosramos@terra.com.br

Availableonline7March2015

http://dx.doi.org/10.1016/j.bjane.2013.11.004

Comparison

between

continuous

thoracic

epidural

and

paravertebral

blocks

for

postoperative

analgesia

in

patients

undergoing

thoracotomy:

meta-analysis

of

clinical

trials

Comparac

¸ão

entre

bloqueios

peridural

e

paravertebral

torácicos

contínuos

para

analgesia

pós-operatória

em

pacientes

submetidos

a

toracotomias:

meta-análise

de

ensaios

clínicos

DearEditor:

Thearticleentitled‘‘Comparisonbetweencontinuous tho-racic epidural and paravertebral blocks for postoperative analgesia in patients undergoing thoracotomy: a system-atic review’’, recently published in the Brazilian Journal

of Anesthesiology, demonstrates the authors’ concern to

showthetherapyeffectivenessforanestheticmanagement ofpostoperativepaininchestsurgeries.1

Reading the scientific article arouses greatinterest to readers; however, some points need to be considered, such as: the softwareused for calculations, the sensitiv-ity analysis method by successive meta-analysis, the use ofmixed-effectmodelanalysis,andthesearchtoidentify statisticalheterogeneity.

Thesoftwareusedinthesearchwasdescribedinthe sec-tionsMethodandReferences,butthelatterisincorrect,and itisimpossibletoidentifytheplacewhereitisavailableand tohaveaccesstothesoftwareforfuturesearchessimilarto this.

Themethodofsuccessivemeta-analysiswasusedbythe authorsatsomepointofthesystematicreviewexecutionto performthesensitivity analysis;however, theoutcome of thisanalysiswasnotreportedintheresults ordiscussion, which did not clarify its realcontribution in this system-aticreview.Thismethodallowstheidentificationofalikely sourceofstatisticalheterogeneityandtheexclusionornot ofthearticle,inanattempttoconsolidatetheresults.2

夽 _{UniversidadeFederaldeAlagoas,Maceió,AL,Brazil.}

Theauthorsreportedtheuseofrandomandfixedeffect modelfor meta-analysiscalculation;however,therandom model was chosen to calculate the meta-analysis when-ever I2 _{was greater than 30%. Inthe analysis of variables} ‘‘assessment of pain at rest after 24h and ‘‘incidence of hypotension’’, the value of I2 _{was lower than that} pro-posed by the authors, notmatching theresearch method description,andtheresultswerealsodescribedbythe ran-dom insteadof fixed effectmethod. The article does not indicatewhetherthisdescriptionoftheresultswasdueto consensusdecisionoftheauthorsorafailuretoconductthe research.

Theauthorsconsideredthepresenceofheterogeneityas aresearchbiaswhentheyreported‘‘(...)theseresultsmay

have beenbiasedbytheincludedstudies heterogeneity’’; however, thepresence ofheterogeneity does notindicate biasinasystematicreview.Testsofheterogeneityareused to determine whether differences between the included studies are genuine (heterogeneity) or if it occurred ran-domlyduringtheanalysis(homogeneity).3_{Ifthedifferences}

occurredrandomly,theresultsfoundinsystematicreviews have more credibility, and if heterogeneity is found, the reasonsshouldbecarefullyevaluatedbytheauthorsto con-solidatetheresultsandnotonlybeconsideredaresearch bias.

It is noticed that the statistical heterogeneity present inmost analysiswaslittleexploredbythe authors,andit is possible to disagree with part of their conclusion that says:‘‘Fromthissystematicreview,itisclearthatepidural analgesia isassociated withahigher incidenceof arterial hypotensionandurinaryretention whenit is usedfor lat-eralpaincontrolafterthoracotomyinadultpatients,with evidencelevel1A’’,aslevel1Arequiresminimalorabsent heterogeneityorthatitisproperlyexploredwhile perform-ingasystematicreview.

In short, I congratulate the authors for the article, which brings important results for the understanding of post-operativepainin thoracicsurgery. Systematicreview conclusions are less incisive regarding the clinical signifi-canceofitsresultswhenthoseoftheincludedstudiesdiffer fromeachother.3

Conflicts

of

interest