Rev. bras. ortop. vol.52 número4

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SOCIEDADE BRASILEIRA DE ORTOPEDIA E TRAUMATOLOGIA

w w w . r b o . o r g . b r

Update

Article

Is

it

safe

to

use

local

anesthesia

with

adrenaline

in

hand

surgery?

WALANT

technique

夽

Pedro

José

Pires

Neto

∗

_,

_Leonardo

_de

_Andrade

_Moreira,

_Priscilla

_Pires

_de

_Las

_Casas

HospitalFelícioRocho,DepartamentodeOrtopediaeTraumatologia,BeloHorizonte,MG,Brazil

a

r

t

i

c

l

e

i

n

f

o

Articlehistory:

Received30August2016 Accepted5September2016 Availableonline19July2017

Keywords:

Localanesthesia/methods Localanesthesia/administration anddosage

Hand Surgery Adrenaline

a

b

s

t

r

a

c

t

Inthepastitwastaughtthatlocalanestheticshouldnotbeusedwithadrenalinefor proce-duresintheextremities.Thisdogmaistransmittedfromgenerationtogeneration.Itstruth hasnotbeenquestioned,northesourceofthedoubt.Inmanysituationsthebenefitofuse wasnotunderstood,becauseitwasoftenthoughtthatitwasnotnecessarytoprolongthe anestheticeffect,sincetheproceduresweremostlyofshortduration.Afterthedisclosureof studiesofCanadiansurgeons,cametounderstandthatthebenefitswentbeyondthetime ofanesthesia.TheWALANTtechniqueallowsasurgicalfieldwithoutbleeding,possibilityof informationexchangewiththepatientduringtheprocedure,reductionofwastematerial, reductionofcosts,andimprovementofsafety.Thus,afterpassingthroughtheinitialphase ofthedoubtsintheuseofthistechnique,theauthorsverifieditsbenefitsandthepatients’ satisfactioninbeingabletoimmediatelyreturnhomeaftertheprocedures.

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

É

seguro

o

uso

de

anestésico

local

com

adrenalina

na

cirurgia

da

mão?

Técnica

WALANT

Palavras-chave:

Anestesialocal/métodos Anestesialocal/administrac¸ãoe dosagem

Mão Cirurgia Adrenalina

r

e

s

u

m

o

Aprendemos quenão deveríamos usar um anestésico local comadrenalina para

pro-cedimentos nasextremidades. Esse dogmaé transmitido de gerac¸ãoem gerac¸ão. Não

questionávamos a sua veracidade ou a origem da dúvida. Em muitas situac¸ões não

entendíamosobenefíciodouso,poismuitasvezespensávamosnãosernecessárioprolongar oefeitoanestésico,jáqueosprocedimentoseram,nasuamaioria,decurtadurac¸ão.Após adivulgac¸ãodeestudosdoscirurgiõescanadenses,passamosaentenderqueosbenefícios seestendiamalémdotempodeanestesia.AtécnicaWalantpermiteumcampocirúrgico

夽

StudyconductedattheHospitalFelícioRocho,DepartamentodeOrtopediaeTraumatologia,BeloHorizonte,MG,Brazil. ∗ _{Corresponding}_author_.

E-mail:pires@felicoop.org.br(P.J.PiresNeto).

http://dx.doi.org/10.1016/j.rboe.2017.05.006

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semsangramento,possibilidadedetrocadeinformaçõescomopacienteduranteo proced-imento,reduçãodematerialdedescarte,reduçãodecustosemelhoriadasegurança.Dessa forma,apóspassarpelafaseinicialdasdúvidasquantoaousodessatécnica,verificamos osseusbenefícioseasatisfaçãodospacientesempoderemretornardeimediatoparacasa apósosprocedimentos.

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

Introduction

Thereisagrowinginterestinperforminghandandwrist surgi-calprocedureswithlocalanesthesiawithoutsedation.Studies havedemonstratedthatsurgicalprocedurescanbeperformed safelyandonanoutpatientbasis.Experiencehasshownthat theuseoflocalanesthesiawithepinephrine,inadditionto providingsafety,allowsintraoperativecontrolofmovement andassessmentoffunctionduringtendonrepairortransfer procedures.

Thisarticleaimedtodiscusspossibilitiesandconcepts,and toassessthesafetyandthetechniquesoflocalanestheticuse withepinephrineinhandsurgery.Patientsoperatedwiththis typeofanesthesiadonotrequiresedation,whichallowsan exchangeofinformationduringtheprocedure,active move-mentoftheoperatedlimb,andafasterhospitaldischargeafter surgery.1

What

is

the

‘wide-awake’

or

WALANT

technique?

The term wide-awake indicates that the hand surgery is

performed with the patient fully awake. WALANT is the

acronym for ‘wide-awake local anesthesia no tourniquet’.

WALANTisthecurrent preferred termtoindicate thatthe

procedure is performed withthe patient in a non-sedated

state, under local anesthesia and without tourniquet. In

this technique, only two drugs are used, lidocaine and

epinephrine.2

Adrenaline

or

epinephrine

Epinephrine,alsoknownasadrenaline,isasympathomimetic

hormoneandneurotransmitter3_derived_from_the

modifica-tion ofan aromatic amino acid (tyrosine) secreted by the adrenalglands,socalledbecausetheyarepositionedabove thekidneys.Thenameadrenalinecomesfromad-(prefixthat indicatesproximity),renalis(pertainingtothe kidneys),and thesuffix-ine,whichappliestocertainchemicalsubstances (amines).

It affects both the beta-1adrenergic receptors (cardiac)

and beta-2 adrenergic receptor (pulmonary). It has

alpha-adrenergicpropertiesthatresultinvasoconstriction.InBrazil, thenameadrenalineispreferred.

Hemostasis

instead

of

a

tourniquet

for

hand

surgery

Manyhandsurgeonshaveswitchedfromtraditionalsurgery

witha tourniquetandsedation tothe WALANTtechnique.

Lidocaine and epinephrine are the only drugs injected for

anesthesiaandhemostasisatthedissectionsites,andatthe Kirschnerwiresinsertionsitesinosteosynthesis.

Benefits

of

WALANT

(1) Nouseofsedationortourniquet,whichincreasespatient comfortandconvenience.Patientscanhavetheirhands operatedsimilarlytoasmallprocedureatthedentist.

(2) Theelimination ofthe anesthesiology/sedation

compo-nents decreasesthe surgicaltimeforthe proceduresin thetreatmentofcarpaltunnelsyndrome,DeQuervain’s tenosynovitis,andtriggerfinger.

(3) Duringtheprocedure,thepossibilityofobservingand cor-rectingsuturedtendonsandofverifyingthestabilityofan osteosynthesiswiththefullrangeofactivemovements,

and with the patient in acomfortable and cooperative

position, allows betterresults intendon repair, tendon transfer,andfixationofphalangealfractures.

(4) WALANTisnotindicatedforallpatients,butmostofthose whocanundergodentaltreatmentswithoutsedationcan alsohavetheirhandsoperatedonusingthistechnique.1

Is

it

safe

to

use

epinephrine

in

the

finger?

Thesafetyofepinephrineuseinthefingerimpliesnoneedto usetourniquet.

Therise and fallofthemyth ofthe dangerofinjecting epinephrineinthefingergoesbacktobeforethe1950s,when surgeons believed that epinephrine caused finger necrosis. Thisdogmahasspreadandrootedintheteachingsin medi-calschools,whereitwascommontoteachthatepinephrine should not be injected into the extremities (fingers, nose, penis,andfeet).Evidence-basedmedicinehasalreadycleared thismisconception.Thefollowingisthestoryofhowthis hap-pened.

The

myth

Thesourceofthe epinephrine myth,whicharosebetween

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Itwas“thenew‘-caine’,”inventedin1903toreplacecocaine. Thislocalanesthetic was used until1948, when lidocaine, whichhasa saferprofile,wasintroduced. Procaine started withapHof3.6;whenstoredforalongtime,itwouldacidify, anditspHwouldreachaslowas1.Itwasthisaciditythat causedfingernecrosis,nottheuseofepinephrine.5_The_Food

andDrugAdministration(FDA)oftheUnitedStatesreported intheJournaloftheAmericanMedicalAssociationthattheyhad foundprocainelotsforinjectioninhumanswithapHof1.6

Is

it

possible

to

reverse

the

effect

of

epinephrine?

Evidence shows that phentolamine, an alpha blocker that

becameavailablein1957,reliablyreversesthevasoconstrictor actionofepinephrine.7_However,_its_use_is_seldom_necessary

inclinicalpractice.8

Theliteraturefeaturesstudiesinwhichepinephrinehas beenusedwithoutinducingnecrosis.8,9

Furthermore,nocasesofnecrosiswerereportedevenwith highdosesofepinephrine(1:1000)afteraccidentalinjections ofepinephrineintoafinger.10,11

Therefore,epinephrineisunlikelytocausedamagetothe fingers at a concentration of 1:100,000. More cases of fin-gerinjurieshavebeenreportedfromimproperlyuseddigital tourniquetsthanfromlidocainewithepinephrine.12,13

Safe

dosage

of

lidocaine

with

epinephrine

• The most widely reported dose of lidocaine with

epinephrine is 7mg/kg. This dosage had already been

suggestedbefore1950,atthebeginningoftheuseof lido-caine.Sincethen,Burketal.14_reported_safe_blood_levels_of

lidocainewhen35mg/kgareinjectedforliposuction. • SincemostpatientssubmittedtoWALANTareoperatedon

anoutpatientbasis,theauthorssuggesttheuseofdosages withintheverysafelimitof7mg/kgformosthand surger-ies.Ina70-kgadult,thismeans:

• Safedosage:lidocaine/epinephrine. <50mL:1/100,000

50–100mL:0.5/200,000 100–200mL:0.25/400,000

The

concentrations

of

premixed

epinephrine

with

lidocaine

vary

by

country.

• InCanadaandintheUnitedStates,theanestheticis pre-mixedas1%lidocainewith1:100,000epinephrine.

• Todate,1%lidocainewith1:200,000epinephrineisavailable

asapre-mixedsolutioninmanyEuropeancountriesand

thisworksverywellforsurgeons.InIsrael,lidocaine pre-mixedwithepinephrineisnotavailable,andthemixture hastobemadebysurgeonsthemselves.InHongKongand Brazil,2%lidocainewith1:200,000epinephrineisavailable aspremix.InEgypt,premixed2%lidocainewith1:100,000 epinephrineisavailable,whileinIndonesia,thepremix2% lidocainewith1:80,000epinephrineisavailable.

• Thereisstillnoevidenceintheliteraturethatprovesan idealanduniqueepinephrineconcentration.

How

to

inject

local

anesthetic

with

minimal

pain

Itispossibleandeasy tolearn andteachmedicalstudents andresidentshowtoinjectlocalanestheticforhandsurgeries. Theauthorsuseathinneedle(13×4.5)andminimizethepain ofthefirstpinch.Patientswillgreatlyappreciatethe physi-cianhavinginvestedthetimeneededtolearnthetensimple rules listedbelow.Themostimportantare rules7through 10.Patientswillbesurprisedandcaptivatedwiththesmall amountofpaintheywillfeelduringtheinjections.15–27

RULE1.Buffer:1%lidocaine,1:100,000epinephrine,and10:1 8.4%sodiumbicarbonate.

RULE2.Donotusearefrigeratedlocalanesthetic. RULE3.Localanesthesiawithsmallneedle(13×4.5). RULE4.Createasensorydistractionintheinjectionsite. RULE5.Stabilizethesyringewithbothhandsandkeepthe thumbreadytopresstheplungertoavoidthepainofa mov-ingneedle.

RULE 6. Inject 0.5mL with a needle perpendicularly just belowthedermisandthenpauseuntilthepatientreports thatthepainofthepinchhasdisappeared(Fig.1).

RULE7.Neverlettheneedleprogressinfrontofthelocal anesthetic(blowslowbeforeyougo)(Figs.2and3).

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Fig.2–“Blowslowbeforeyougo”injectiontechnique.The anestheticisinjectedslowlybeforetheneedleis

progressed.Inthisway,thenerveendingswillbeblocked bytheanestheticandtheprocesswillbepainless(Courtesy DonaldLalond).

RULE8.Reinsert theneedle atleast1cminto thealready injectedarea.Thiscanbedefinedbypalpationorassessing thecoloroftheskin;

RULE9.Askeachpatienttogiveascore(0–10)regardingthe intensityofpainduringtheinjectionoftheanesthetic. RULE10.Morelocalanestheticisbetterthaninsufficientlocal anesthetic.

Palmar

and

dorsal

scars

and

folds

are

natural

barriers

to

the

diffusion

of

the

local

anesthetic

solution

• Thelocalanestheticdoesnotdiffusewellintothescars.It willoftenbenecessarytoinjectlocalanesthetic onboth sidesofalinearscar.Formarkedlyscarredareas,the sur-geonshouldtrytoinitiatetheinjectionfromtheproximalto distalandintohealthysubcutaneoustissue,andthenfinish underthescarifnecessary.

Fig.3–Blockadewithlidocaineandadrenaline30min beforethesurgicalprocedureforcarpaltunnelrelease.

• Allnaturalskinfoldsonthehandandwrist,aswellasthe foldsbetweenthefingersand palm, haveligaments that attach the skin to deeper structures, such as the flexor sheaths.Thesecanslowthediffusionoftheswollenlocal anesthetic to the other side ofthe fold. Thelocal anes-theticwillcrossbelowtheskinfold,butonlyslowly,under pressure,andatlargevolumes.Itissensibletoinjecton bothsidesofthenaturalfolds,fromproximaltodistal,to decreasetheinjectionpain(Fig.4).

Epinephrine

and

vasovagal

syncope

adverse

reaction

Althoughlidocaineandepinephrineareprobablytwoofthe safestmedicationsinuse,injectingthemcancauserelatively commonsideeffects.Afterinjectionoflocalanestheticwith epinephrine,thepatientmayexperiencesymptomsof agita-tion,tremors,andnervousness.Thevasovagalreactionmay appearinresponsetoneedlepenetration.

Lossofconsciousnessor faintingafter avasovagal

syn-cope occurs because there is notenough blood going into

thebrain.Nature’ssolution,fainting,bringstheheaddown toallowmorebloodtoreachthebrainthroughtheeffectof gravity.

Asimplechangeofbandagesortheremovalofaplaster castmaycausefainting.Thepinchofaneedle,withorwithout localanesthesia,isalsoanothercommontriggerforfainting (vasovagalsyncope).

Ifthepatientshowssignsthathe/sheisabouttofaint,more blood can besenttothe brainwithsimplegravity-shifting maneuvers.

If the patientissitting,the surgeoncan askhim/herto liedown.Injectionofanestheticintheseatedpositionisnot recommended.

Ifthepatientislyingdown,he/shecanbeaskedtoplace thehandsunderthekneesandraisethembyflexingthehips andknees,sothatthebloodfromthelowerlimbsincreases cerebralirrigation.

Thesurgeonshouldremovethepillowunderthepatient’s headandplaceitunderhis/herfeet.

Thesurgeoncanalsoleantheheadofthebedtothe Tren-delenburgposition(headdownandfeetup).28,29

Tips

on

how

to

talk

to

patients

about

WALANT

Forpatients,thefearoftheunknownandanxietyaboutpain

arethetwomainconcernsofbeingawakeduringthehand

surgery.However,iftheprocessisexplainedtopatientscalmly, clearly,andconfidently,thefearoftheunknowncanbe over-come.Bygainingknowledgeoftheprocedure,thepatientcan feellikeanactiveparticipantinthetreatmentprocess,awake andcooperative.Ifthelocalanestheticinjectionhappensas described aboveandwithafine needle,thepatient willbe surprisedathowbriefandmildthediscomfortwillbe.

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Fig.4–(A)Blockadewithlidocaineandadrenalineproximalanddistaltothewristfold;(B)beginningofthe vasoconstrictioneffectafter15min;(C)completeeffectafter30min.

Thepatientmay talk tothe physicianduringthe injec-tion of the local anesthetic. A slow injection will be less painful.

Afterfinishingtheinjection,thepatientmayfeel alittle nervousorabitagitated,asiftheyhavehadtoomuchcoffee. Theyshouldbeinformed thatthisisnotaneffectofbeing nervous,butratherthefactthatthereisabitofepinephrine inanestheticmedication.Thissensationiscompletelynormal andnotdangerous.Ifthishappens,itisimportanttomention thatitwilldisappearin5–30min,andthatitdoesnotmean thatsomethingiswrong.

The patient should be informed that they will feel

their hands cold and moist and that, during the surgery,

they will feel pulling and moving in the operated

site.

Aftersurgery,theywillsimplygetupandgohome;their handwillfeelasifitwasbiggerthantheirheart.Thepatients willhavesomerestriction.Theyshouldkeepthelimbelevated toreduceswellingandpain.

Talking

to

patients

during

surgery

Whenhandsurgeryisperformedwithsedation,itisnot pos-sibletoguidepatientsduringtheprocedure.Sedationdoes notallowthepatienttorememberwhatthephysicianspoke

tothemduetodrugsthatcause amnesia.When usingthe

WALANTtechnique,orientationpassedtothepatientduring surgeryisfoundtobeveryuseful.Duringtheprocedure, sur-geonscanguidetheirpatientsaboutpost-operativecareand onhowtoavoidcomplications.

Thetimespenttalkingtopatientsduringsurgeryisatime savedbeforeoraftersurgery.

Thistimewillhelptoreducethecomplicationsthatcould takeplaceinthepostoperativeperiod.

Things

that

should

not

be

said

or

done

during

surgery

Never say somethinglike “oops.”Surgeons must createan

atmosphereofcalmness,efficiency,andcompetence. Asilentsurgeonmayseemquitecompetent,whiletheone whotalksalotwithoutlisteningtothepatientcannotreassure him/her.

Thepatientwillbefullyawakeandattentivetoeverything thathappens.Therefore,whenorderinginstrumentsfromthe

roomnurse,surgeonsmustdosousingsignsortermssuch

as“number15”instead of“scalpelblade15”.“Singlehook” shouldbeusedinsteadof“skinhook”.

The surgeon should avoid passing compresses,

gauze, or instruments with blood in front of the

patient.

Sterile

surgical

drapes

for

simple

cases

Inthesterilesurgicalfield,smalldrapessheetsthatarethe sizeofcompressspongesareused(fenestrated40cm×40cm

sheet). The surgeon wears a mask and sterile gloves, and

does not wear a sterile apron. Therefore, only the drape

used willbe sterile,asin skincancer removalprocedures.

Studies have shown that, for some hand surgery

proce-dures, the steriledrape issufficient, does notincrease the

risk of infection, and reduces the cost by four times or

more.30–33

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Fig.5–(A)Carpaltunnelreleaseapproachunderlidocaine/adrenalineeffect;(B)aftertheprocedureandstillunder lidocaine/adrenalineeffect,maintainingabloodlessoperatingfield.

Increased

revenue

and

reduced

costs

with

WALANT

• Iftheneedofatourniquetiseliminatedandalocal anes-theticisinjectedinanalmostpain-freeprocedure,thetwo mainreasonsfortheneedofsedationinmosthand sur-geriesareremoved.Oncepatientsunderstandthebenefits ofWALANT,mostwillnotwantsedationforhandsurgery (Fig.5).

• Theeliminationofsedationalsomeansthatmanyhand sur-geriescanbeeasilyperformedinsmallerprocedurerooms, whereonlytheoperativefieldissterile,inthesamewayas skintumorsareremoved.

• Theeliminationofthetourniquet,sedation,andtheneed foracompletelysterileroomforhandsurgerywhenusing

WALANTincreasespatient safetyandconvenience while

loweringcosts.Itreducesunnecessaryspendingsandmore patientswillbenefitfromhandsurgeries.33

• Eventually, insurance companies and governments will

understandthatsedationisnotnecessaryformanyhand surgeries. They will become receptive to the concept of increasingpatientsafetyandconveniencewhilelowering costs.

• Over time, insurance companies and governments will

be made aware of evidence-based medicine that

sup-ports the concept that a sterile field is safe and far

less expensivefor many hand surgeries. Thiswill lower costs.

• Negotiationbetweenhealth careproviders,insurers, and thegovernmentwillbenecessarysothatsomesurgeries

canbeperformedusingtheWALANTtechniqueinsimpler

operatingrooms.Certainly,everyonewillbereceptivetothe conceptofincreasingpatientsafetyandconveniencewhile loweringcosts.

Theaccreditation process forasurgical roomthat does

not use sedation is less expensive than that of a

facil-ity that uses sedation or general anesthesia. If sedation

is not used, the costs of its equipments and medications

disappear.

Final

considerations

Surgicalproceduresofthehandwiththepatientfullyawake

are beingpracticedbyagrowingnumberofhandsurgeons

in mostcountries ofthe world. This number isincreasing

becausethetechniqueissafer,moreconvenient,andmuch

moreaccessibleforbothpatientsandsurgeons.

These innovations depend on the cultural changes of

physicians, patients, institutions, and healthcare plans or insurersresponsibleforthecostsoftheprocedures.Surgeons mustrememberthattheyarealsoresponsibleforthecosts. MostsurgeonswhohavetestedWALANTcontinuetouseit.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

r

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f

e

r

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n

c

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s

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