Rev. Bras. Anestesiol. vol.67 número6

666 LETTERSTOTHEEDITOR anesthesiatoablate the rise in pulmonary vascular

resis-tanceassociatedwithsurgicalstimuliisoneoftheprimary goalsinanesthesiamanagementofthesepatients,whatwas thereasontousesevofluraneasasoleanestheticagentina cardiacpatientwithpersistentpulmonary hypertension,if earlypostoperativeextubationwasnotplanned?

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

References

1.Altay N, Yuce HH, Aydogan H, et al. Airway management in newborn with Klippel---Feil syndrome. Braz J Anesthesiol. 2016;66:551---3.

2.NaguibM,FaragH,IbrahimAel-W.Anaestheticconsiderationsin Klippel---Feilsyndrome.CanAnaesthSocJ.1986;33:66---70.

3.Creighton RE,Relton JE, Meridy HW. Anesthesia for occipital encephalocoele.CanAnaesthSocJ.1974;21:403---6.

4.BakanM,Umutoglu T,ZenginSU,et al.Thesuccess ofdirect laryngoscopy in childrenwith Klippel---Feil syndrome. Minerva Anestesiol.2015;81:1384---6.

MefkurBakan

BezmialemVakifUniversity,FacultyofMedicine,

DepartmentofAnesthesiologyandReanimation,Istanbul, Turkey

E-mail:mefkur@yahoo.com

http://dx.doi.org/10.1016/j.bjane.2017.04.003 0104-0014/

©2017PublishedbyElsevierEditoraLtda.onbehalfofSociedade BrasileiradeAnestesiologia.Thisisanopenaccessarticleunder theCCBY-NC-NDlicense(http://creativecommons.org/licenses/ by-nc-nd/4.0/).

Effects

of

lidocaine

and

magnesium

sulfate

in

attenuating

hemodynamic

response

to

orotracheal

intubation:

a

single-center,

prospective,

double

blind,

randomized

study

Os

efeitos

da

lidocaína

e

do

sulfato

de

magnésio

na

atenuac

¸ão

da

resposta

hemodinâmica

à

intubac

¸ão

orotraqueal:

estudo

unicêntrico,

prospectivo,

duplamente

encoberto

e

aleatorizado

DearEditor,

ItwaswithgreatpleasurethatIreadthearticle‘‘Effects oflidocaineandmagnesiumsulfateinattenuating hemody-namicresponsetoorotrachealintubation:asingle-center, prospective,doubleblind,randomizedstudy’’.1_Concerned

to clarify some points related to the statistical analy-sis and conclusion; here are some considerations to the authors:

1. The authorsreportadiscretestatisticaldifferenceand thisdoesnotallowthearticle’sreadertocometo conclu-sions: ‘‘Therewasastatistically significantincrease in SBP (p=0.018) and DBP (p=0.0467) values measured post-TI(Fig.2),butof littleclinicalimportance’’. The valuesshouldhavebeendemonstratedintextbecause, as shown in Fig. 2, it is not possible to capture its

DOIofreferstoarticle:

http://dx.doi.org/10.1016/j.bjane.2015.08.004

magnitude,sothatthelackofclinicalimportancedoes notrepresentabsenceofbiologicalrelevance;

2. The data werepartiallyor totallyanalyzed over time, and the patients were also submitted to anesthetics in addition to the medications tested, which may be in addition or not. It is known that magnesium sul-fate has a prolonged clinical effect after venous use, whereas lidocaine has a short protective effect com-paredtomagnesium. Thus, therearetwofactors that mustbeconsideredinthisstatisticalanalysis:timeand treatment. The beststatistical test toperform in this situation is two-way ANOVA.2 _{The results analyzed as}

they are in the text may be erroneously positive and thepossibilityofatypeIerrorinthisresearchisclearly perceived;

3. Ifthe authors considerthe use ofthe Student’s ttest as correct, or more appropriately in some cases the Mann---WhitneyUtest,accordingtothetext,theyshould havecorrectedthepvaluewiththeprocedurefor multi-plecorrectionofhypothesistests,insteadofconsidering only5%asthelevelofsignificanceinallanalyzes.The possibilityof having a positive resultin the statistical analysisoccurringat randomis5%.Thep-value correc-tion would have reduced the probability of a random occurrenceofthestatisticalresult.Thus,thepossibility oftypeIerrorinthisresearchisclear;

LETTERSTOTHEEDITOR 667 also be reviewed by the authors, effectiveness is the

termsuggested;

5. Finally,Ileaveasarecommendationtheobservationto theauthorsthattherearelargerdoses,equallysafeand equally effective, that could have been tested in this clinical trial and increased the degree of information relatedtothetopic.3

I congratulate the authors for the brilliant initiative, while celebrating at thesame timethe possibilityof cre-atingthislineofresearchinanesthesiainBrazil.Thankyou fortheopportunitytocontributetothistopic.

Conflicts

of

interest

Theauthordeclaresnoconflictsofinterest.

References

1.Mendonc¸aFT,QueirozLMGM,GuimarãesCCRG,etal.Osefeitos dalidocaínaedosulfatodemagnésionaatenuac¸ãodaresposta

hemodinâmica à intubacão orotraqueal: estudo unicêntrico, prospectivo, duplamente encoberto e aleatorizado. Rev Bras Anestesiol.2016.Emprocessodepublicac¸ão.

2.KimHY.Statisticalnotesforclinicalresearchers:two-way analy-sisofvariance(ANOVA)---exploringpossibleinteractionbetween factors.RestorDentEndod.2014;39:143---7.

3.BarbosaFT1,BarbosaLT,JucáMJ,etal.Applicationsof magne-siumsulfateinobstetricsandanesthesia.RevBrasAnestesiol. 2010;60:104---10.

FabianoTimbóBarbosa

CentroUniversitárioTiradentes,CiênciasdaSaúde, Maceió,AL,Brazil

E-mail:fabianotimbo@yahoo.com.br

http://dx.doi.org/10.1016/j.bjane.2017.04.009 0104-0014/

©2017PublishedbyElsevierEditoraLtda.onbehalfofSociedade BrasileiradeAnestesiologia.Thisisanopenaccessarticleunder theCCBY-NC-NDlicense(http://creativecommons.org/licenses/ by-nc-nd/4.0/).

Reply

to

the

letter

to

the

Editor

Resposta

à

carta

ao

Editor

DearEditor,

WethankBarbosa’s1_{letterinwhichheappreciatesourwork}

andpraisesthestudy‘‘Effectsoflidocaineandmagnesium sulfateinattenuatinghemodynamicresponsetoorotracheal intubation:asingle-center,prospective,double-blind, ran-domizedstudy’’carriedoutinourservice.2_Forus,author

andauthor’sguesttowritethisreplay,itisonlyfairthatwe respondwithattention toall questions,withinour limita-tions:

(1) Question:Theauthorsrefertoadiscretestatistical dif-ference,which does notallow the readertodrawhis ownconclusions:‘‘GroupMhadastatisticallysignificant increaseinSBP(p=0.018)andDBP(p=0.0467)post-OTI (Fig.2),butof littleclinical importance.’’The values shouldbedemonstratedintextbecause,asitisinFigure 2,itisnotpossibletocapturethemagnitudeofthem,so thatthelackofclinicalimportancedoesnotrepresent absenceofbiologicalrelevance.

DOIofreferstoarticle:

http://dx.doi.org/10.1016/j.bjane.2015.08.004

夽 _{Author’sreplytotheLettertotheEditor:Effectsoflidocaine} and magnesiumsulfate inattenuating hemodynamicresponseto orotrachealintubation:asingle-center,prospective,double-blind, randomizedstudy.

RegardingItem1,itwasreallyflawed,butnot inten-tional,onourparttoomitthesedata.Themissingdata areonTable1.

(2) Question:Datawere,inpartorinwhole,analyzedover timeandpatientsalsoreceivedanesthetics,inaddition tothemedicationstested,whichmaybeadditionalor not.Itisknownthatmagnesiumsulfatehasaprolonged clinicaleffectaftervenoususe,whereaslidocainehasa

Table1 Comparisonofthemean±standarddeviationof bloodpressureinmmHgatthedifferenttimesofthestudy.

SBP GroupL GroupM p-Value

Admission 139±19.1 137.7±17.7 0.8072 Post-MDZ 119.9±15.5 123.5±14.3 0.4055 CIPend 122.9±17.7 120.9±16.6 0.6657 Post-IND 90.9±16.1 96.5±16.3 0.1912 Post-OTI 119.5±24.6 134±24.6 0.0180a

3′_{Post-OTI 108.1±22.3 116.2±16.2 0.1482}

6′_{Post-OTI 96.8±17.3 105.9±16.2 0.0520}

DBP GroupL GroupM p-Value

Admission 85.7±12.6 84.6±11.5 0.7680

Post-MDZ 75.4±10.7 77.7±10.2 0.4473

CIPend 79.6±11.8 75.2±15.1 0.2646

Post-IND 55.1±11 57.3±11.3 0.4956

Post-OTI 77±19.9 87.4±15.2 0.0467a

3′_{Post-OTI 68.1±18.3 70.4±12.8 0.6189}

6′_{Post-OTI 59.6±14.9 62.1±11.6 0.5192}

SBP, systolicbloodpressure;MDZ,midazolam;CIP,continuous infusionpump;IND,induction(ofanesthesia);OTI,orotracheal intubation;DBP,diastolicbloodpressure.

a