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UNIVERSITYHOSPITAL,GEELONGFELLOWSHIPWRITTENEXAMINATION
WEEK15–TRIALSHORTANSWERQUESTIONSSuggestedanswersPLEASELETTOMKNOWOFANYERRORS/OTHEROPTIONSFORANSWERSPleasedonotsimplychangethisdocument-itisnotthemastercopy!
Question1(18marks)
a. CompletethetabletodistinguishbetweentheclinicalfeaturesofGuillain-BarréSyndromeandMultipleSclerosis.(4marks)
History Guillain-BarréSyndrome MultiplesclerosisAgeatonset Typicalonset:20-40yroldOnset Insidious
Postinfection/Sx/Immunisation/malignancyEpisodic,relapsing,remitting
Distribution AscendingmotorparalysisGlove&stockingloss
Random,eyesoften1st
Limbpain Passivemovement/calfpaincommon Electricshocksensationsinlegs,worsewithneckflexion
Visualdisturbance Opthalmoplegiarare OpticneuritisPainfuleyemovementsVA/fielddefects
CerebralFx IntellectualdemiseSeizures
Naturalcourse >90%recovery Stabilise&improveProgressive
Sex Female:male2:1b. CompletethetabletodistinguishbetweentheexaminationfeaturesofGuillain-BarréSyndromeandMultiple
Sclerosis.(4marks)Examination Guillain-BarréSyndrome Multiplesclerosis
CN 50%facialnorbulbar Common,espeyesION,RAPDCerebellarsigns Rare MaybepresentGait weakness SpasticTone ↓ ↑,clonusReflexes ↓/flaccid(LMN) ↑(UMN)Autonomic Common Rare-sensory-BladderdysfunctionRespiratorycompromise ↓FEV1
RespiratorysupportmayberequiredRare
c. Listthetwo(2)investigationsofchoicetoassistwiththediagnosisofMultipleSclerosis.Statetwo(2)diagnostic
findingsthataresupportiveofMultipleSclerosisforeachinvestigation.(6marks)Investigationofchoice1: CSFexaminationSupportivefindings:
• (90%)<10cells/ml-Tlymphocytepredominance• Normalprotein• Iggy(↑in80%)
o Oligoclonalbands(85-90%ofclinicalMS)Investigationofchoice2: MRIBrainSupportivefindings:
• Subcorticalandperiventricularplaques(50%)• Enhancementindicatesactivity/resolveswithremission
d. AssumingthediagnosisofGuillain-BarréSyndrome,whichdrugmustnotbegivenifintubationisrequired?(2
marks)• Sux • Precipitationoflifethreateninghyperkalaemia(absolutelycontraindicatedinpatientswithGBS.There
havebeenanumberofcasereportsofseverehyperkalaemia,lifethreateningarrhythmias,andcardiacarrestafteritsadministrationinGBS)
e. Listthetwo(2)optionsfortreatmentofGuillain-BarréSyndrome.(2marks)• IVImmunoglobulin• Plasmaphoresis(usuallynotbothtogether,it’saneither/or)
“List”=1-3words“State”=shortstatement/phrase/clause
GuillainBarreSyndrome§ Commonestcauseofrapidonsetparalysisinpreviouslyhealthyperson.§ Bothsexes.Allages§ Acutepolyneuropathy1-4weekspost:
§ 70%postviralURTI/gastro§ Postoperative§ Postimmunisation§ Intercurrentmalignancy
§ Pathology→neuronitiswithmyelindestructionand∴Walleriandegenerationofneurones
ClinicalfeaturesSensory§ Initialparaesthesiainhandsandfeet→minorgloveandstockingloss(sensoryneuropathyisusuallyminimal)§ Posteriorcolumnvibration/proprioception>spinothalamicMotor§ Progressiveascendingmotorweaknessaffecting>1limb→distalmmweaknesswithoutatrophy(25%prox>distal)§ Areflexia/markedhyporeflexia§ Limbpainonpassivemovement/calfpain§ CNin~50%→usuallyfacialnnorbulbar(allexceptI,II,VIII,extraocularmmrarelyinvolved) -MillerFischervarianthaspredominantCNinvolvementOther§ Nofever/neckstiffness,normalmentalstate§ Autonomicdysfunction -Badprognosticindicator -Verysensitivetocardiacdrugs→mayarrestonintubation -Ileus,retention,assoc.SIADH
Investigations Dx -CSFprotein↑in90% >0.4g/l -CSFcountnormal
-FET→monitorprogress Tx -ABG -RFT -Excludeothercauses
Management§ CVS,Respsupport§ SUXAMETHONIUMASSOCIATEDWITHSUDDENDEATH§ Nutrition→enteral,parenteral§ Plasmaphoresis -Superiortosupportivealone -Bestifcommenced<7daysafteronset -↑speedofrecovery -Nochangetoultimatemortality§ ImmunoglobulinRx -ProbablyasusefulasplamaphoresisPrognosis§ Good→mostfullrecovery§ Worseprognosisif: -autonomicinvolvement
-deficitnot↓in3/52§ 2%mortality→resp.failure§ 10%majorresidualdeficitDDxofacuteascendingmotorparalysis§ Rhabdomyolysis§ Tick/snakebite§ Diphtheria/polio/botulism§ PANDDXautonomicneuropathy
§ DM§ ETOH§ Amyloid
Multiplesclerosis§ Commonestchronicneurologicalcondition§ Onset30-40’s,60%F§ 20%asymptomaticthroughlife§ HigherincidenceinTas,lowerasgonorthinAus§ Pathology→ Extensivewhitematterplaques,lossofoligodendrocytes,axonalsparing Conductiondisturbedbyfever,stress,electrolyteimbalance(lossofsuppressorTcellsb4attacks)
Clinicalfeatures
§ Episodicattacksoffocalneurologicaldeficit→sensory,motororsphincter§ Predilectionforspinalcord,brain,opticnerves§ Over2-14/7thenremission§ ~½presentassinglesignorsymptom§ Common→limbweakness,opticneuritis(painwiteyemovements,↓VA),sensorysymptoms,diplopia
1. Spinalcord→ commonestmanifestation§ limbweaknessin40%,UMNsigns(spasticgait,↑tone,clonus,↑reflexes),postcolumnloss§ painfulspasms§ bladderdysfunction,constipation§ Lhermittessign→painfulelectricshocksdownlegs↑byneckflexion
2. Opticneuritis→40%atsomestage,presentingsymptomin20%Significantpainwitheyemovementispresentinnearlyeverycaseofdemyelinatingopticneuropathy
§ VAoverdays,centralscotoma,usuallyunilateral§ disturbedcolourperceptionearlysign§ visualfielddefects§ painoneyemovement§ Ex:50%papillitisonfundoscopy,relativeafferentpupilliarydefect§ 40%goontoMS§ 1/3completelyrecover,partially,notatall§ Uhthoff’sphenomenon→↓visiondtexercise,hotmeal/bath
3. Brainstem→ common§ Diplopia,III,IV,VICNlesions§ InternuclearopthalmoplegiaalmostDxofMSorSLE AbnoofMLF→ipsilateraladductioninability,contralaterallat.gazenystagmus§ Bell’spalsy§ Vestibularneuronitis→vertigo,vomiting,nystagmus§ Cerebellarsigns
4. Cerebral→ Intellectualdemise§ Depression§ Seizures~5%§ Rare→dysphasia,hemiparesis,homonymoushemianopia
Diagnosis§ Involvementofdifferentpartsofnervoussystem,2separateoccasions,lasting>24/24orslowprogressionover6/12§ Requires2anatomicallyseparatelesions§ Delayedvisual/auditory/somatosensoryevokedpotentials§ LP→ 90%<10cells/ml,mainlyTlymphocytes,↑IgG,proteinnormal§ MRI→detectsdemyelinatedareas,subcorticalandperiventricularplaquesvisualisedin50% Enhancementindicatesactivityofdisease
DDxEye Retinala/vocclusion Opticnerveglioma MethanolingestionSCdisease Cxspondylosis Subacutedegeneration
Hereditaryataxias SCcompressionCerbral HIV
PosteriorfossaSOL SLE Sarcoid
Mx
§ Acute→highdosemethylpred,ACTH80U,PNL§ Preventrelapses→Azathioprine,cylophosphamide,interferon,plasmaphoresis§ Symptomatic→baclofenforspasms,carbamazepineforpain,urinarycatheter,boweltraining
Opticneuritis
§ Mono-ocularvisionchanges,especiallyinayoungfemaleshouldpromptyoutothinkingaboutthiscondition.§ Opticneuritis(decreasedvisualacuity,relativeafferentpupillaryafferentdefect)caneasilybemistakenforpapilledema
(visualacuityandpupillaryreflexesarenormal)§ Makingthediagnosiscanbedifficultinthatthemajorityofpatientsmayactuallyhaveanormalfundoscopicexambutgivea
classichistoryfor"retrobulbarneuritis"(visionchangesandpainespeciallywitheyemovement).§ Theclinicalpresentationofdemyelinatingopticneuropathyvaries.§ PatientsfrequentlypresenttotheEDwithanacutelossofvision.§ ThenaturalhistoryofMS-relatedvisionlossisrapidlyprogressiveacuitylossforaperiodof10days,whichthen
stabilisesandimproves.§ Additionalocularsignsincludeeyepain,tendernessoftheglobe,dyschromatopsia,decreasedbrightnesssense,decreased
colourperception,arelativeafferentpupillarydefect,assortedvisualfielddefects(altitudinalandcentral/cecocentral),phosphenesuponeyemovementandopticdiscswellingwithorwithoutvitreouscells.Often,theopticnerveisnormalinappearanceandthedysfunctionisconsideredretrobulbar.
§ Demyelinatingopticneuropathycandamagethefibersinboththevisualandpupillarypathways.Thisdamageinterruptsnerveimpulseswithinthepathways,producingdecreasedvisionaswellasanafferentpupillarydefect.
§ Systemicsignsandsymptomsmayincludeheadache,nausea,Uhtoff’ssign(decreasedvisionwithorwithoutlimbweakness
followingexposuretoincreasedtemperaturesi.e.,abathorexercise),Romberg’ssign(patientfallswhentheyclosetheireyes),Pulfrich’sstereophenomenon(beerbarrelappearancetotheenvironment)andfever.
§ Asrecordedinthethree-yearfollow-upofpatientsRxwithintravenousmethylprednisolonefollowedbyoralcorticosteroid
regimensreducedthetwo-yearrateofdevelopmentofclinicalMS,particularlyinpatientswithsignalabnormalitiesconsistentwithdemyelinationonMRIofthebrainatthetimeofstudyentry.Serioussideeffectsofglucocorticoidtherapyareinfrequent.Therefore,outpatientadministrationofhigh-doseintravenousglucocorticoidsmayberecommended.
ClinicalPearls
• AnumberofothertypesofdemyelinatingdisordershavebeenassociatedwithON.Theyare: acutetransversemyelitis
Guillain-BarrésyndromeDevic’sneuromyelitisopticalCharcot-Marie-Toothsyndromemultifocaldemyelinatingneuropathyacutedisseminatedencephalomyelitis.
• Diseasessuchassyphilis,toxoplasmosis,histoplasmosis,tuberculosis,hepatitis,rubella,humanimmunodeficiencyvirus(HIV),Lymeborreliosis,familialMediterraneanfever,Epstein-Barrvirus,herpeszosterophthalmicus,paranasalsinusdisorder,sarcoidosis,systemiclupuserythematosus,Bechet’sdisease,anddiabetesmaycauseopticneuropathyandshouldbeconsideredbeforeprematurelydiagnosingdemyelinatingopticneuropathy.
• Incasesofopticneuropathypresumablysecondarytodemyelinatingdisease,MRIcanassistinsystemicdiagnosisbyidentifyingbotholdandacutedemyelinatingplaqueswithinperiventricularwhitematter.
• Significantpainwitheyemovementispresentinnearlyeverycaseofdemyelinatingopticneuropathy.• Asthevisualdysfunctionisduetoautoimmunedestructionofmyelinandnotdirectinflammationoftheopticnerve
tissue,thisdiseaseentityisbesttermeddemyelinatingopticneuropathy.
Papilloedema
Optic neuritis
Question2(11marks)
A35yearoldmanisbroughtintoyouremergencydepartmentafteranisolatedinjurytotheleftanklesustainedinamotorcycleaccident.Hisobsare:BP160/50mmHgsupineHR110/minGCS15
a. State(4)featuresshownonthisxraythatsuggestasevereinjury.(4marks) • Complete#throughtheneckoftalus• Severecomminutionoftalus• Separationofthemajorfragments>1cm• MarkedanteriordisplacementofdistalfragmentNB:notdislocation/subluxationasanklejointisintact
Heisdeliveredbyambulanceandhasreceivedonlypenthraneenroute.Hedoesnothaveintravenousaccessonarrival.Heisextremelydistressedwithpain.Helastate2hoursago.Hisweightis70kg.
b. Listseven(7)analgesicoptionsforthispatientwhileheisintheemergencydepartment.Includedosesandrouteswhereapplicable.Includeinitialdosesandroutewhereappropriate.(7marks)• Initialoptions:
§ IMketamine3-5mg/kg§ INfentanyl1mcg/kg§ N20
• IVmorphine-5-10mg• Sedationforreduction:
§ IVketamine1-1.5mg/kg§ IVmidazolam3-5mg
• Reduction/immobilisation• Elevation• Ankleblock10-20mlx0.5%plainbupivacaine• PCA• Oraloxycodone/paracetamol
Question3(12marks)A65yearoldfemale,non-Englishspeaking,Italianladypresentswithabout1cupofhaemoptysis.Youare
unabletoobtainanymedicalhistory.Herobservationsare:BP135/65mmHgHR80/minGCS15a. Listfour(4)likelydifferentialdiagnosesforthispresentation.(4marks)• TB• PE• Pneumonia-severewithinfarction• LungCa-primary/secondary• Pulmonaryabscess• Coagulopathy/overanticoagulation• Thrombocytopaenia• Pulmonarycontusion• InhaledFB
b. OtherthanaCXR,listthree(3)keyinvestigationsthatyouwouldconsiderorderinginthe
emergencydepartment.(3marks)NB:listonly-noqualificationneeded
• INR• Sputum-AFB,MCS• CTChest• CTPA • ECG,FBE,UE,LFT,QuanteferonGold,ECHO
AChestXrayshowsunilateralchanges.Sheexperiencesalargevolumehaemoptysis(estimatedbloodloss500ml).
c. Listfive(5)keystepsinthetreatmentofthispatientoverthenext30minutes.(6marks)NB:500mlismassive/lifethreateninghaemoptysis• Communication-Interpreter-obtainfocussedHx/explaintopt• Nursewithaffectedsidedown-Preserveunaffectedlung• Ventilationsupport-Mainstemintubationorcombitube/duallumentubetononaffected
sideonly(anaestheticassistance)• Circulation-Volumereplacement-blood-massivetransfusionifindicated• Reverseanticoagulation-FFP/VitK/Prothrombinex/Tranaxemicacid• Rxunderlyingconditions-PneumoniaIVabs/PE-anticoagulation• Isolation-IfTbexpectedNB:ReferinterventionalXR-Ifbleedingpersistswillprobablybeafter30min
Question4(17marks)A64yearoldmanisbeingevaluatedinyouremergencydepartmentafteranepisodeofchestpainwhichhasnowresolved.Heisgivenaspirinonlyenroutetohospital.2010/1/6.Hisobservationsare:BP140/85mmHgRR20/minO2saturation97%roomair
a. Statefour(4)abnormalfindingsshowninthisECG. (4marks) • Bradycardia~48bpm• Mobitztype1(Wenchebach)2nddegreeHB• STE1mmII,V2-V6• BiphasicTWIIIVi
b. Listfour(4)likelycausesforthesefindings.(4marks)
• Ischaemia• Drugs--vechronotropes(BB,CCB,Digoxin)-therapeutic• Drugs-ODegsameasabove• Cardiomyopathy• Myocarditis
Thepatientbecomessuddenlyunwell.He is lightheadedwithnochestpain. HisBP is70/50mmHg.He isgivena500mlfluidboluswithnoimprovement.
c. Statefive(5)abnormalfindingsshowninthisECG.(5marks)• Rate25-30• CHB• Ventricular/IdioventricularescapeorQRSprolongation• RAD• TWIII,III,V1-V3
(ForQwavestobesignificanttheyneedtobe: >40msec&>2mmdeep&>25%depthofQRS)
d. List in order of escalation, your choice of drug treatment for this patient. Specify dose and route. (4marks)
Drugtreatment Dose1stline Isoprenalineor
AdrenalineBolus20-40mcgIVFollowedbyinfusion0.5-20mcg/min
2ndline Atropine 300mcg-600mcgIV(rarelyeffective)
Question5(14marks)
Aseriesofthree(3)Xraysfromthree(3)differentpatientsareshowninthepropsbooklet
a. ForXray1,statewheretheforeignbodylies.(1mark)
• Loweroesophagusatthegastro-oesophagusjunction. b. ForXray1,listtwo(2)optionsforthenature/compositionoftheforeignbody.(2marks)
• Coin• Roundmetalobject
c. Listtwo(2)factorsthatwouldmandateurgentremovaloftheforeignbody.(2marks)• Excessivesymptoms
o Unabletoswallowo Severepain
• Complicationso Haematemesiso Featuresofperforation
d. ForXray2,wheretheforeignbodylies.(1mark)
• Oesophagus-upper e. ForXray2,whatisthenature/compositionoftheforeignbody?(1mark)
• Buttonbattery f. ForXray2,stateyourdisposition.Providetwo(2)pointsofjustificationforthischoice.(2marks)
• Disposition:Theatre-AdmitGastro/ENT• Justification: Immediateremovalrequired(MANDATORY)(<2/24)
Extensivesurroundingtissuedamagecommences<30min Toolargetoallowwaitandseeifpassageoccursspontaneously
g. ForXray3,wheredoestheforeignbodylie?(1mark)• Upperoesophagus
h. ForXray3,stateyourdisposition.Providetwo(2)pointsofjustificationforthischoice.(3marks)Disposition:AdmitGastro/ENT
Justification: Toolargetopassspontaneously Timingofremovaldependsonsymptoms
Question6(12marks)A45yearoldmanwithtype1diabetesmellitusisbroughtinbyambulancewithanalteredconsciousstate.Hisobservationsare:BP90/70mmHgHR120bpmTemperature36.8 °COxygensaturation97%on8LbyHudsonmaskGCS12E4,V3,M5
a. Providethree(3)calculationstohelpyoutointerprettheseresults.(3marks)
1. CorrectedNa(NeedtocorrectNapriortoAGcalculation)• TrueNa= measuredNa+ + glucose-10/3
Or measuredNa+ + glucose-7/3.5 Or measuredNa+ + glucose/4
2. AnionGap=21∴↑3. Deltagap∆ratio:~1.7∴PureHAGMA 4. Others:
o ExpectedCO2o A-agradient274-247=27∴normalforageo SeOsmo
b. Provideaunifyingexplanationforthisclinicalpicturebasedontheseresults.(3marks)
• HAGMetabolicacidosis-LikelyDKA• 1°respiratoryacidosis-Likelyhypoventilation• Renalimpairment-slightlyincreasedUr:Crlikelypartlyprerenalfromdehydration
c. Complete the following table demonstrating three (3) key specific treatment tasks in the first 2 hours of the
emergencydepartmentstay.Statehowyouwouldachieveeachofthesetasks.
Keytreatmenttask Howwillyouachievethetask?
1 Establish U/O/ correcthypovolaemia
Fluid1LNSStat~250ml/hrfornext4/24MonitorU/OwithFBC(avoidIDC)CVPmonitoring
2 Correcthypoglycaemia FluidsInsulin0.1U/kg/hr(max15U/hr)Followlocalprotocol3-5U/hr
Kbalance ReplaceKasglucosefallsandKfalls Airwayprotection Carefulobservationgivenalteredconsciousstate Treatprecipitant EgSepsis
DeltaratioThisDeltaRatioissometimesusefulintheassessmentofmetabolicacidosis.Asthisconceptisrelatedtotheaniongap(AG)andbuffering,itwillbediscussedherebeforeadiscussionofmetabolicacidosis.TheDeltaRatioisdefinedas:
Deltaratio=(IncreaseinAnionGap/Decreaseinbicarbonate)Howisthisuseful?Inordertounderstandthis,considerthefollowing:Ifonemoleculeofmetabolicacid(HA)isaddedtotheECFanddissociates,theoneH+releasedwillreactwithonemoleculeofHCO3
-toproduceCO2andH2O.Thisistheprocessofbuffering.TheneteffectwillbeanincreaseinunmeasuredanionsbytheoneacidanionA-(ieaniongapincreasesbyone)andadecreaseinthebicarbonatebyone.Now,ifalltheaciddissociatedintheECFandallthebufferingwasbybicarbonate,thentheincreaseintheAGshouldbeequaltothedecreaseinbicarbonatesotheratiobetweenthesetwochanges(whichwecallthedeltaratio)shouldbeequaltoone.Thedeltaratioquantifiestherelationshipbetweenthechangesinthesetwoquantities.ExampleIftheAGwassay26mmols/l(anincreaseof14fromtheaveragevalueof12),itmightbeexpectedthattheHCO3
-wouldfallbythesameamountfromitsusualvalue(ie24minus14=10mmols/l).IftheactualHCO3
-valuewasdifferentfromthisitwouldbeindirectevidenceofthepresenceofcertainotheracid-basedisorders(seeGuidelinesbelow).ProblemAproblemthough:theaboveassumptionsaboutallbufferingoccurringintheECFandbeingtotallybybicarbonatearenotcorrect.Fiftytosixtypercentofthebufferingforametabolicacidosisoccursintracellularly.ThisamountofH+fromthemetabolicacid(HA)doesnotreactwithextracellularHCO3
-sotheextracellular[HCO3-]willnotfallasfarasoriginallypredicted.Theacidanion(ieA-)howeverischargedandtendsto
stayextracellularlysotheincreaseintheaniongapintheplasmawilltendtobeasmuchaspredicted.Overall,thissignificantintracellularbufferingwithextracellularretentionoftheunmeasuredacidanionwillcausethevalueofthedeltaratiotobegreaterthanoneinahighAGmetabolicacidosis.Caution:Inaccuraciescanoccurforseveralreasons,forexample:• Calculationrequiresmeasurementof4electrolytes,eachwithameasurementerror• Changesareassessedagainst'standard'normalvaluesforbothaniongapandbicarbonateconcentration.Sometimestheseerrorscombinetoproducequiteanincorrectvaluefortheratio.Asanexample,patientswithhypoalbuminaemiahavealower'normal'valueforaniongapsousingthestandardvalueof12tocompareagainstmustleadtoanerror.Donotoverinterpretyourresultandlookforsupportiveevidenceespeciallyifthediagnosisisunexpected.GuidelinesforUseoftheDeltaRatioSomegeneralguidelinesforuseofthedeltaratiowhenassessingmetabolicacid-basedisordersinprovidedinthetablebelow.OverallAdvice:Beverywaryofover-interpretation-Alwayscheckforotherevidencetosupportthediagnosisasanunexpectedvaluewithoutanyotherevidenceshouldalwaysbetreatedwithgreatcaution.
DeltaRatio AssessmentGuideline
<0.4 Hyperchloraemicnormalaniongapacidosis
0.4-0.8 ConsidercombinedhighAG&normalAGacidosisBUTnotethattheratioisoften<1inacidosisassociatedwithrenalfailure
1to2 Usualforuncomplicatedhigh-AGacidosisLacticacidosis:averagevalue1.6DKAmorelikelytohavearatiocloserto1duetourineketoneloss(espifpatientnotdehydrated)
>2 Suggestsapre-existingelevatedHCO3levelsoconsider:• aconcurrentmetabolicalkalosis,or• apre-existingcompensatedrespiratoryacidosis
Warning:Beverywaryofover-interpretation-Alwayscheckforotherevidencetosupportthediagnosisasanunexpectedvaluewithoutanyotherevidenceshouldalwaysbetreatedwithgreatcaution.AhighratioAhighdeltaratiocanoccurinthesituationwherethepatienthadquiteanelevatedbicarbonatevalueattheonsetofthemetabolicacidosis.Suchanelevatedlevelcouldbeduetoapre-existingmetabolicalkalosis,ortocompensationforapre-existingrespiratoryacidosis(iecompensatedchronicrespiratoryacidosis).Withonsetofametabolicacidosis,usingthe'standard'valueof24mmol/lasthereferencevalueforcomparisonwhendeterminingthe'decreaseinbicarbonate'willresultinanoddresult.AlowratioAlowratiooccurswithhyperchloraemic(ornormalaniongap)acidosis.Thereasonhereisthattheacidinvolvediseffectivelyhydrochloricacid(HCl)andtheriseinplasma[chloride]isaccountedforinthecalculationofaniongap(iechlorideisa'measuredanion').Theresultisthatthe'riseinaniongap'(thenumeratorinthedeltarationcalculation)doesnotoccurbutthe'decreaseinbicarbonate'(thedenominator)doesriseinnumericalvalue.Thenetofofboththesechangesthenistocauseamarkeddropindeltaratio,commonlyto<0.4LacticacidosisInlacticacidosis,theaveragevalueofthedeltaratioinpatientshasbeenfoundtobeis1.6duetointracellularbufferingwithextracellularretentionoftheanion.Asageneralrule,inuncomplicatedlacticacidosis,theriseintheAGshouldalwaysexceedthefallinbicarbonatelevel.DiabeticketoacidosisThesituationwithapurediabeticketoacidosisisaspecialcaseastheurinarylossofketonesdecreasestheaniongapandthisreturnsthedeltaratiodownwardstowardsone.Afurthercomplicationisthatthesepatientsareoftenfluidresuscitatedwith'normalsaline'solutionwhichresultsinaincreaseinplasmachlorideandadecreaseinaniongapanddevelopmentofa'hyperchloraemicnormalaniongapacidosis'superimposedontheketoacidosis.Theresultisafurtherdropinthedeltaratio.
Question7(12marks)
A65yearoldmanpresentswithalefthandinjury.
a. Listtwo(2)factorsthatarisefromthisimage,thatwouldsuggestapoorprognosisforsuccessful
reimplantation.(2marks)• Site-throughmiddlephalanyxorDIP• Tendonavulsion• Macerationofedges• (Paletiporavulsedpartsnotstoredappropriatelyatpresent-clutchingstraws)
b. Listsix(6)historicalfactorsthatwouldsuggestapoorprognosisforsuccessfulreimplantation.(6marks) • Timeofinjury/delaytorepairWarmischaemia>6badandcoldischaemiatime>12bad• Age• SmokingHx Mostimportant• PVD • Diabetes• Steroiduse• Delay/incorrectcoolingofamputatedparts• Hypotension• Proximalinjurytoarm/forearm
c. Howwouldyoustoretheamputatedpartspendingadecisionforpotentialreimplantation?List
two(2)pointsinyouranswer.(2marks)• Doublesealedbag(orbottomshelffridge)• Iceslurry
d. Whatisthemostappropriateregionalanaesthesiatechniqueforthispatient?(1mark)• Combinedradialandmediannnblock• orUSguidedscaleneblock• orvolarplateblock
NB:Notringblock-maypranganartery
Amputations
Careofamputatedparts Xray WashgrosscontaminationwithsterileNS→wrapinsterilegauzelightlysoakedinNS→doubleplasticbaginice/water Orlowertrayfridge Aimtokeepcoolavoidfreezing
Careofstump RemoveanytorniquetappliedbyMAS Directpressurewithsteriledressings-combine Novascularclamping Directedtemporarytourniquet
-onlyifuncontrollablebleedingenroutetotheatre
Timetoreimplantation-ishaemiatime Warm6-8hrs Cool12hrs(upto24hrs)
PrognosticfactorsforfavourableoutcomeAmputatedpartfactors Cleancutvscrush/shear/degloving Durationoftimebetweeninjuryandsurgery Minimalcontamination/infection Minimalwater/shrinkageeffectatedges Site/musclecontent →wristbetterthanforearm→tendonsrepairbetterthanmuscle →fingersdowellifamputateddistaltoFDPorproxFDSinsertion(worstbetDIP&PIP) →worstiftwolevelinjuryPatientfactors Age→childrendobetter Preexistinghealth(DM,PVD,steroidsdoworse) →smokerspoorsuccessrate
Relativecontraindicationstoimplantation Longdurationbetweentimeofinjury→Sx(>6/24warm,>12coldischemiatime) CrushwithextensiveSTI Peripheralvasculardisease Grosslycontaminated/infectedwound Devitalisedtissue Otherlife-threateninginjurieswhichtakeprecendence Siteofamputationinpresenceofsignificantneurologicalinjury(egBPdisruption)
Don'tforgetIVAbsTetanusprophylaxis-toxoid+/-TIGAnalgesiaSplintFastManagementofotherinjuries-Secondarysurvey
Question8(12marks)
A6yearoldboypresentswithaleftsupracondylarhumeralfracture.
a. Listtwo(2)typeofpainscoringsystemsthatyoucouldapplytothischild.(2marks)• WongBakerFaces (3-18)• FLACC (2/12-18)• Visualanalogue (6-18)NB:Numerical (8+yrs)
b. Listtwo(2)reasonswhyapainscoreisused.(2marks)
• Objectiveassessmentofpainispoor• Allowsassessmentofefficacyofanalgesia
c. Listfour(4)indicationsforGAMPinthispatient.(4marks)
• Distalneurocompromise• Distalvascularcompromise• Skincompromise• Capitellumposteriortoanteriorhumeralline(dorsalangulation>10°)• <50%bonycontact• Medial/lateralangulationEspif>10°• Anteriordisplacement
d. Listfour(4)piecesofadvicethatyouwouldgivetothisboy’sparentifthepatientisabletobe
dischargedfromtheemergencydepartment.(4marks) • Postsedationadvice• PostPOPadvice
§ Indicationstoreturnforreview• POPcheckplan• Analgesiaadvice• Followuparrangements
ClickontheimagebelowtoviewtheentirePDF(&print/saveifnecessary)
Question9(12marks)
A46yearmanisbroughttoyouremergencydepartmentwithsuspectedalcoholwithdrawal.
a. List seven (7) of the 10 scale domains that form theAlcoholWithdrawal Assessment Scale (7marks) • N&V• Tactiledisturbance• Tremor• Paroxysmalsweating• Auditorydisturbance• Visualdisturbance• Anxiety• Agitation• Headache• Orientationandcloudingofsensorium
A35yearoldmaleisidentifiedashaving“verysevere”alcoholwithdrawal.
b. Statefive(5)keymanagementstepsforthispatientoverthenext1hour.(5marks)• Nonstimulatingenvironment• Provideadequatehydration• RxThiamine&multivitamins• Rxhypoglycaemia• IVdiazepam5mg-repeatto4xover1st30minthen30minutelyasrequired
This resource is produced for the use of University Hospital, Geelong Emergency staff for preparation for the Emergency Medicine Fellowship written exam. All care has been taken to ensure accurate and up to date content. Please contact me with any suggestions, concerns or questions. Dr Tom Reade (Staff Specialist, University Hospital, Geelong Emergency Department) Email: [email protected] November 2017