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?