REGIONAL ANESTHESIA –

CLINICAL UPDATE AND REVIEW

Jason Wilson, PhD MD FRCPC Regional Anesthesia Fellow

St Paul’s Hospital, Vancouver BC November 5, 2016

PANBCAnnualEducationDay

OBJECTIVES

• Whyusearegionaltechnique?• Isitsafe?BetterthanaGA?

• Discusscommonlyusedregionaltechniques:• Outcomes,rationale,andsafety• UpperandLowerextremityblocks• Relevantanatomy• Commonlyusedperipheralnerveblocks

• Discusslocalanesthetictoxicity(LAST)andotherperi-opcomplications• Discussperioperativemanagement/dischargemanagementofpatientsreceivingsingleshotperipheralnerveblocksandindwellingperineuralcatheters

• Ensuringadequatedischargepaincontrolandavoidingsecondaryinjurytoablockedlimb

WHY USE REGIONAL ANESTHESIA?

• Isn’tageneralanestheticsimplerandequallyeffective?

• Aren’ttheoutcomesthesameregardlessofwhenaregionaltechniqueisusedornot?

General Anesthesia vs Regional Anesthesia• Regionalanesthesiahelps:

• Avoidadifficultairway• Minimizesedatives/opioidsinhigh-riskpatients• COPD,ObstructiveSleepApnea,ChronicPain

• Avoidphysiologiceffectsofgeneralanesthesiainfragileorhighlycomorbidpatients• Obesity,significantcardiacorrespiratorydisease,renalfailure

• AVFistulacreationsurgery

General Anesthesia vs Regional Anesthesia Continued…

• ReducePost-opNauseaandVomitting(PONV)insusceptiblepatients

• “Fast-track”healthypatientstopost-recoveryareas,improvingPACUefficiency

• Ifminimalsedation,patientscanbypassPACUandprogresstodaycareearlier

• HealthyPatients

IS A REGIONAL BLOCK FOR EVERYONE?IMPORTANT QUESTIONS TO ASK THE PATIENT

• Coagulationstatus• DetailedPainHistory• SignificantMedicalComorbidities• Previoushistoryofanyanestheticcomplications• Occupation

• Theseareaswillhelpdeterminetheoptimalpatientsforanerveblock

AREN’T THE OUTCOMES THE SAME ?

•RegionalAnesthesia:• Improvespaincontrol&increasessatisfaction1•Reducesopioidconsumption2•Reducesriskofchronicpost-operativepain3• Insomepatientpopulations,reducespulmonarycomplications&mortality4

•Reduceshospitallength-of-stay5

1-Whiteetal.AnesthAnalg2005.101:25-s22.2-Pauletal.Anesthesiology2010.113(5);1144-623-Andreaeetal.CochraneDatabaseSystRev20124-Neumanetal.Anesthesiology2012.177:72-92

5-Lenartetal.PainMed2012.13:828-34

WHAT ABOUT COMPLICATIONS?

• RegionalAnesthesiaisassociatedwith:• FailedBlocks(afrustratingnuisance…)• IntravascularInjection• Infection• Pneumothorax• NerveInjury

• PermanentandTransient• SurgicalComplications(inrareinstances;i.e.maskedcompartmentsyndrome)• LocalAnestheticToxicity(LAST)

Fortunately,throughcarefulpatientselection,effectivemultidisciplinarycommunication,andtheonsetofUltrasoundforblockplacement,seriouscomplicationsareextremelyrare!• Arisk:benefitdiscussionmustbecompletedwitheverypatientpriortostartingtheblock

WHY REGIONAL? - SUMMARY

• Inthecorrectpatientpopulationregionalanesthesiaisverysafeandcancontributetobetterpaincontrolanddecreasedpost-operativecomplications

REGIONAL ANESTHESIA TECHNIQUES

• EssentiallyANYperipheralnerve,plexus,orgroupofnervescontainedwithintheneuraxiscanbeblocked!

• Upperextremityblocks• Lowerextremityblocks

UPPER EXTREMITY BLOCKS

• Surgicalanaesthesiaoftheupperextremitycanbeachievedbytwogeneralmeans:

• Blockadeatthebrachialplexuslevel• Blockadeofspecificperipheralnerves

• ThebrachialplexusisderivedfromspinalnerverootsfromtheC5-T1levels

UPPER EXTREMITY – BRACHIAL PLEXUS

• Anappropriateblockischosenbasedonsensorydistributionofbrachialplexusbranches

•Notallbrachialplexusblocksprovidethesameblockdistribution.

BRACHIAL PLEXUS – INTERSCALENE

• Appropriateforanesthesiaoflateralshoulder,upperarm,andelbow• Frequentlyspareslowestnerveroots(C8/T1)

• Notthebestforhandsurgery

• Idealforshoulder&claviclesurgery

BRACHIAL PLEXUS – INTERSCALENE

C5

C6

C7

BRACHIAL PLEXUS – SUPRACLAVICULAR

• Mostversatilebrachialplexusblock.Mostcommonupperextremityblock

• The‘Spinalofthearm’

• Generallyforsurgerybelowmid-humerus

• I.e.notappropriateforshouldersurgery

• Rapidonset,denseblock

BRACHIAL PLEXUS – SUPRACLAVICULAR

BRACHIAL PLEXUS – SUPRACLAVICULAR

“Inplane”lateraltomedialapproachtosupraclavicularbrachialplexusblock

BRACHIAL PLEXUS – INFRACLAVICULAR

• Similarusesassupraclavicularblock• NOTsuitableforupperarm/shouldersurgery• Mostcommonlyusedforhand/wristsurgery

• Approachtothebrachialplexusisbelowtheclavicleasthenervebundlecomestogetherwiththeaxillaryartery

BRACHIAL PLEXUS – INFRACLAVICULAR

BRACHIAL PLEXUS – AXILLARY

• Blockofthedistalnervebranches• Higherincidenceof‘patchy’blocksorunblockedareas

• Duetothefactthatbranchesofplexusarestartingtoseparatethisdistalfromcervicalroots

• Musculocutaneousnervecommonlymissed• Anterolateralforearm/wrist

BRACHIAL PLEXUS – AXILLARY

BRACHIAL PLEXUS BLOCKS: POTENTIAL SIDE EFFECT AND COMPLICATIONS

• Horner’sSyndrome• Interscalene>Supraclavicular>Infraclav

• Symtoms:Ptosis,Miosis,Anhydrosis

• Cause:Localanestheticspreadtothesympatheticchainthatinnervatestheeyesandface

• Treatment:SelflimitingonceLAwearsoff

BRACHIAL PLEXUS BLOCKS: POTENTIAL SIDE EFFECT AND COMPLCATIONSPhrenicNervePalsyCommonwithinterscaleneandsupraclavicularblocks• Symptoms:DyspneaorlowOxygensaturation

• Cause:Localanestheticspreadtothephrenicnerve.

• Treatment:SupplementalOxygen• SittingPosition

• WillimproveonceLAwearsoff• Mustensurethatdyspneaisnotcausedbyamoreseriousetiology

• R/Opneumothorax

BRACHIAL PLEXUS BLOCKS: POTENTIAL SIDE EFFECT AND COMPLCATIONS

SecondaryInjurytotheArm• Themajorityofthearmisanesthetizedforseveralhours.

• Predisposesittoinjuryandburns

• Requirediligentprotectionofthearm!• Weartheprovidedarmsling• Avoidboilingliquids

PERIPHERAL NERVE BLOCKS

• Theperipheralnervestothehandoranklecanbeblockeddistally.

• Thisisprimarilydoneforverysmallsurgicalproceduresoraspartofarescueblock

LOWER EXTREMITY – LUMBAR PLEXUS

LOWER EXTREMITY – SACRAL PLEXUS

Sciaticnerveistheprimarynervearisingfromthesacralplexus• Largestnerveinthebody• Derivedfromnerverootsof

L4-S3• Providesthebulkof

sensationfromtheleg

LOWER EXTREMITY – SCIATIC NERVE

• Sciaticnerveblockisusefulfor:• Surgeryoffoot,ankleandlowerleg• Adjuncttofemoralblockinkneesurgery• Combinedwithfemoral,canachievealmosttotalanesthesiaoflowerextremity

LOWER EXTREMITY – SCIATIC NERVEAnatomyandDermatomes

SCIATIC / POPLITEAL NERVE BLOCK

• Inthepoplitealfossa,thesciaticdividesintoperoneal&tibialbranches

• Goalistofindthebifurcationandblockproximaltothat

LOWER EXTREMITY – FEMORAL NERVE

• Easyandusefulblockforpainmanagementoftheknee,shinandmedialankle

• Seldomadequateforsurgicalanesthesia• Mainlyusedfororthopedicsprocedures

• VastmajorityareKneereplacementandFoot/Anklesurgery

• CausesMotorWeaknessoftheQuads–notidealforpost-opphysiotherapy

• Providesgoodanalgesiaofanteriorthigh,femur,andanteriorknee

• Combinedwithsciaticblock,youcanachieveverygoodlowerlimbanalgesia

LOWER EXTREMITY – FEMORAL NERVE

Ultrasoundguidedfemoralnerveblock

LOWER EXTREMITY – SAPHENOUS NERVE BLOCK

• Thegoalistoblockthissensorynerveafterithassplitfromtheprimaryfemoralnerve

• Ideally,nosignificantlegweaknesswillresultaftertheblock

• Greatforkneereplacementsurgerywheremobilityisencouragedpostoperatively

SAPHENOUS NERVE BLOCK

COMBINATION: SAPHENOUS AND SCIATIC BLOCK

• Usedforlowerextremitysurgery• Providescompleteanalgesiatolegbelowknee• Footandanklewillrequirebootorotherprotectivedevice.

• Patientwillrequirecrutchesorwheelchair

PERIPHERAL NERVE BLOCK DURATION

• Thedurationoftheblockisdependentonthetypeoflocalanestheticused• LidocainevsRopivicaine/Bupivicaine

• Newadjuvantmedicationsarebeingaddedtothelocalanesthetictoincreasethedurationofanalgesia

• Thisisanareaofongoingresearch• LysosomalLidocainepreparationsarebeingdevelopedthatcanprovide>48hrblocks

RoughEstimate(Ropivicaine):• UpperExtremity

• 12-24hrs• LowerExtremity

• 24-30hrs

PERINEURAL CATHETERS

• Essentiallyallperipheralnerveblockscanbemade‘continuous’withaperineuralcatheter

• Practicallyspeaking,thefollowingaremostcommon/useful:• Sciatic(Extensivefoot/anklesurgery)• Infraclavicular(Extensivehand/wristsurgery)• Interscalene(Extensiveshouldersurgery)

PERINEURAL CATHETERS

• Commonlocalanestheticinfusionsforperineuralcathetersinclude:

• Bupivicaine0.125%(6-10mL/hr)• Ropivicaine0.1-0.2%(6-10mL/h)

• Thegoalisexcellentanalgesia,withpreservedmotorfunction-thesesolutionsaregenerallydiluteenoughthatprofoundmotorblockisavoided

• Infusionpumpsareavailableinmosthospitals

• Patientcontrolledinfusionpumps(withbolusoptions)arealsoavailable

• SimilartoopioidPCA

PERINEURAL CATHETERS – AT HOME

• Homeperineuralcatheterscaneasilybeusedbymostpatients!

• Disposable,single-usepumpsareavailable,cost-effective,andsafe

• Cansignificantlyimprovepaincontrolallowingday-surgerybookingforcasesthatwouldotherwiserequireadmissionforpaincontrol

• Patientremovescatheterathomewhenlocalanestheticisfinished,ifblocknotlongereffective,orifLAsideeffectsareobvious

HOME PERINEURAL CATHETERS

LOCAL ANESTHETIC - TOXICITY!

• Maxdoses:• Lidocaine(5-7mg/kg)• Bupivicaine/Ropivicaine(2-3mg/kg)

• Asimplerule-of-thumbcalculation:• 1mL/kgof0.25%solution=2.5mg/kg• 0.5mL/kgof0.5%solution=2.5mg/kg• Thesearethemaxvolumesyoushouldgiveeitherasasinglebolusdose,orover4hoursasaninfusion

LOCAL ANESTHETICS - TOXICITY!

• Signs/SymptomsofToxicity• Peri-oralnumbness/Dizziness/Tinnitus• Blurredvision/Disorientation/Drowsiness• MuscleTwitching/Convulsions/Seizure• Coma/RespiratoryDepression• CardiovascularCollapse!

LOCAL ANESTHETICS - TOXICITY!

Initialmanagement:• Declareemergency,callforhelp,callcodeblue,O2,IVaccess

• STOPanyongoingLAinfusions!(i.e.epidural)

• Bringcrashcartandairwayboxtobedside,attachdefibrillatorleadsandpaddles

• ACLSEvidencesupports20%IntralipidasarescuetherapyinCVcollapsefromLAtoxicity

PERIOPERATIVE MANAGEMENT AND DISCHARGE CRITERIA

Singleshotperipheralnerveblocks• D/Ccriteriaasperyourlocalhospital• Ensuretheblockedlimbissafe• Discussapost-oppaincontrolplan• ScreenforSx/Sxofcomplicationsfromthenerveblock

• LAST• Dyspnea• Horner’sSyndrome• Pneumothorax

PERIOPERATIVE MANAGEMENT AND DISCHARGE CRITERIA CONTINUED…

• TheblockWILLWEAROFF• Highincidenceofpaincrisisafterblockresolves.Patientsmustbeinstructedinadequatepaincontroloptions(POmeds)

• ManypatientsrequireEmergencyvisitsforthepaincrisis

• WeinstructourpatientstobegintakingthePOopioidsPRIORtotheblockwearingoff

• Asktheblockphysicianwhenthatwillbe.

PERIOPERATIVE MANAGEMENT AND DISCHARGE CRITERIA

Indwellingperineuralcatheters• Theattendinganesthesiologistwillensurethatappropriateinstructionshavebeengiventothepatient

• Admittedpatientswillbeseendailybytheacutepainservice• Homeinfusionpumpwillbesetupandprogrammedbyattendinganesthesiologist

• Patientsreceivedailyphonecallstoreviewtheeffectivenessoftheblockandtoruleoutanysignsoflocalanesthetictoxicity

SUMMARY

• Regionalanesthesiacanbeusedforincreasedpatientcomfortand/ortoavoidageneralanestheticinspecificpatientgroups

• Regionalanesthesiaissafeandeffective• Thereareupperandlowerextremitynervesthatcanbeblocked,dependingonthespecificsurgery

• Complicationsfromthenerveblocksarerarebutmustberecognizedearly

• Patientsmustbegivenappropriateteachingregardingeffectivepainmanagementstrategiesandavoidingsecondaryinjurytoblockedlimbspriortodischarge

THE END!

• References:• nysora.com(NYSchoolofRegionalAnesthesia)

• usra.ca(UltrasoundGuidedRegionalAnesthesia)

• neuraxiom.com• netterimages.com• TheJournalofBoneandJointSurgery2012

• Questions?