Outcome among patients who call the emergency medical service (EMS) due to dizziness

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ContentslistsavailableatScienceDirect

Australasian

Emergency

Care

j ourn a l h o m ep a g e :w w w . e l s e v i e r . c o m / l o c a t e / a u e c

Research

paper

Outcome

among

patients

who

call

the

emergency

medical

service

(EMS)

due

to

dizziness

Niclas

Packendorff

a

_,

_Victoria

_Gustavsson

a

_,

_Carl

_Magnusson

b

_,

Magnus

Andersson

Hagiwara

c,∗

_,

_Katarina

_Jood

d

_,

_Johan

_Herlitz

c

_,

_Christer

_Axelsson

c

a_The_Emergency_Medical_Service_System_in_Gothenburg,_Sweden

b_Institute_of_Medicine,_Department_of_Molecular_and_Clinical_Medicine,_The_Sahlgrenska_Academy,_Gothenburg_University,_SE-405₃₀_Gothenburg,_Sweden c_Centre_for_Prehospital_Research_Faculty_of_Caring_Science,_Work_Life_and_Social_Welfare,_University_of_Borås,_SE-501₉₀_Borås,_Sweden

d_Department_of_Clinical_Neuroscience_and_Physiology,_The_Sahlgrenska_Academy_University_of_Gothenburg,_SE-405₃₀_Gothenburg,_Sweden

a

r

t

i

c

l

e

i

n

f

o

Articlehistory: Received7April2020

Receivedinrevisedform5June2020 Accepted3July2020

Keywords:

EmergencyMedicalService Dizziness

Etiology Outcome

a

b

s

t

r

a

c

t

Background:Patientwithdizzinessarechallenginginprehospitalcare.

TheaimwastodescribeﬁnaldiagnosisamongpatientsassessedbyEMSassufferingfromdizziness withfocusontime-criticalconditions.

Methods:ConsecutivepatientsassessedbyanEMSclinicianduring12monthsinasinglelargeEMSsystem inGothenburg,Sweden(660,000inhabitants),wereassessed.ThestudycomprisedpatientsgivenESS code11dizziness.Themainend-pointwastheﬁnaldiagnosis(ICDcode).

Results:Therewere58,575primarymissions,ofwhich2,048(3.5%)wereassessedasESScode11 (dizzi-ness).Ofthese,161(8%)wereexcluded.Amongtheremaining1887cases,therewere230differentICD codesand96(5%)hadatime-criticalcondition.Themajority(88%)hadacerebrovasculardisease.The mosttypicalsymptomsamongtime-criticalconditionswereanacuteonset(63%)andnausea,vomiting (61%).Whencomparedwithnon-time-criticalconditions,thosewithtime-criticalconditionswereolder andhadahighermediansystolicbloodpressureatEMSarrival.

Conclusion:AmongprimarymissionsbytheEMS,3.5%haddizziness.Ofthese,5%hadatime-critical conditionandthemajorityhadacerebrovasculardisease.Instrumentstoidentifytime-criticalconditions amongpatientsseenbyEMSduetodizzinessarerequired.

Introduction

Dizziness is a relatively common symptom that may force patientstoseekemergencycare.Manyofthesepatientsdialthe emergencynumberinSweden(112)forambulancetransportto hospital.

Dizzinessisaunifyingconceptforanumberofdifferent expe-rienceswhichthepatientsoftendescribeasfeelingsofbringon acarousel,offbalance,nearsyncopeormotionofthesea.Ithas beenreportedthat aboutthree percentof alladmissions toan emergencydepartment(ED)areduetosymptomsofdizziness[1].

∗ Correspondingauthor.

E-mailaddresses:niclas.packendorff@gmail.com

(N.Packendorff),Victoria.g1981@gmail.com(V.Gustavsson),

cw.magnusson@gmail.com(C.Magnusson),magnus.hagiwara@hb.se

(M.AnderssonHagiwara),Katarina.jood@neuro.gu.se(K.Jood),Johan.herlitz@hb.se

(J.Herlitz),christer.axelsson@hb.se(C.Axelsson).

Anumberofconditionscanbeassociatedwithsymptomsof dizziness.Damagetocentralorperipheralpartsofthevestibular systemwillgenerateanacutevestibularsyndrome.

Whenthedamageislocalisedintheinnerearorinthe vestibu-larnerve,thereisaperipheralaetiology.Examplesofperipheral aetiologies of an acute vestibular syndrome are benign parox-ysmalpositional vestibularneuritis,Ménière’s disease,bacterial labyrinthitisandherpeszosteroticus[2].

In“centraldizziness”,thedamageislocalisedincentralpartsof thevestibularsysteminthebrainstemand/orcerebellumandthe underlyingaetiologiesincludestroke/TIA,migraine,tumourinthe brainstem,encephalitisandmultiplesclerosis[2].

However,ithasbeensuggestedthatthemajorityofpatients withacutevertigohaveotheraetiologies,whicharenotassociated withdamagetothevestibularsystem.Lametal.reportedthat63% ofpatientswithacutedizzinesshadsomethingotherthandamage tothevestibularsystem[3].Themostcommonaetiologieswere anupper airwayinfection(35%) and hypertension(18%).

Time-https://doi.org/10.1016/j.auec.2020.07.001

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criticalconditionssuchassepsis,bradycardia,AVblockIIIandacute coronarysyndromeaccountedforaboutthreepercentofallcases. A further categorisation of vertigo was made by Newman-Tokeretal.,who included9000casesofvertigointheirsurvey [1].Morethanhalfthepatientshadanaetiologywhichwasnot relatedtothevestibularsystem.Thestudyconﬁrmedthatthere is often a medical disease behind symptoms of vertigo which isnot related tothevestibular system.Time-critical conditions whicharenotrelatedtothevestibularsystembutmaystillcause dizzinessand includewater-electrolyteimbalance, arrhythmias, cerebrovasculardiseases,carbonmonoxidepoisoningandaortic dissection/aneurysm.

Thevarietyofconditionsthatmayexistbehindsymptomsof dizzinesshighlight thedifﬁcultieshealth-careproviders experi-enceindifferentiatingthesesymptomsintobenignandmalignant conditionsattheﬁrstencounterwithpatientswhopresentwith thesesymptoms.

The burden on the emergency medical service (EMS) has increasedmarkedlyduringthelastfewdecades.Thisphenomenon isexplainedbyanumberoffactors,includingthedevelopmentof anelderlypopulationandthefactthatmorepeoplenowadaystend tocallforanambulanceduetolesstime-criticalconditions.Ithas thusbeenshownthatnotallpatientswhodial112needtobe trans-portedtoanEDbutcanpreferablybehandledatanotherlevelof care[4].Thishasincreasedthedemandonhealth-careproviders intheEMSwho,alreadyatanearlystage,needtobeableto dis-tinguishpatientswithatime-criticalconditionfromthosewithout anddonotrequireemergencycare.

Onesymptomthatmaycreatedifﬁcultiesintheearly assess-mentonEMS arrivalisdizziness.Thisisexplained bythelarge numberofpossibleunderlyingaetiologiesofwhichsomearetime criticalbutthemajorityarenot.Arecentstudyofpatientswith TIA/strokedescribingpatientswhowerenotdirectlytransported tohospitalaftertheassessmentbyEMS,duetofailureintheearly identiﬁcationindicatedthatmanyofthesepatientshaddizziness asthedominantsymptom[5].

Theaimofthepresentstudyisthereforetodescribeconsecutive patientswhocallfortheEMSduetosymptomsofdizzinesswiththe emphasisontheinitialpresentationtotheEMSclinicianandthe ﬁnaldiagnosis,i.e.underlyingcondition.Particularattentionwill bepaidtowhetherthepatientswereorwerenotsufferingfroma time-criticalconditionaccordingtotheﬁnaldiagnosis.

Methodsandmethods

Design

Thiswasaretrospective,consecutive,observational,pilotstudy witha quantitativeapproach which wasperformedthroughan evaluationoftheEMSandhospitalmedicalrecords.

Studysettingandpopulation

ThestudywasperformedinGothenburg,whichisthesecond largestcity inSweden,locatedonthewest coast,with660,000 inhabitantsandanareaof900km[2].IntheEMSsystem,there are20advancedlifesupport(ALS)ambulancesmannedbyatleast oneregisterednurse(oftenwithaspeciﬁceducationin prehospi-talemergencycare).Thiseducationinvolveseitherpostgraduate educationoraprogrammeinprehospitalemergencycare.There arealsotwoso-calledsingle-responderunitsmannedby experi-encedregisterednursesalwayswithaneducationinprehospital emergencycare.Thereisalsoonephysician-mannedunitwithan anaesthesiologistandaregisterednurse.

In2016,therewere58,575primarymissionswithinthe organ-isationofwhich 2048(3.5%)receivedtheEmergencySignsand Symptoms (ESS) code11 (dizziness)fromthe nurse. Thiscode includedalltypesofdizziness.

“Primarymission”meansthattheEMSnursemakesthepatient assessmentonscene.

Patientrecruitment

In2016,alltheprimarymissionsinthecatchmentareawithESS code11(dizziness;n=2048)wereincludedinthestudy.

Theinclusioncriteriawerethus:

1)PrimarymissionassessedbytheEMSnurse 2)ESScode11(dizziness)

Theexclusioncriteriawere: 1)Age<16years.

2)Patientbeingassessedbyanothercaregiver,i.e.aphysicianat anoutpatientclinic.

3)ThelackofanassessmentbyaphysicianattheED. 4)Thelackofacompleteidentiﬁcationnumber.

5)Thepatientwassenttoanotherhospitaloutsidethecatchment area.

Datacollection

Datawerecollectedfromthehealth-careprovider’snotification intheEMSrecordsintheEMSdatasystem,Ambulink.A simulta-neousanalysisofthehospitaldatabase,Melior,towhichAmbulink islinked,wasperformedwiththeemphasisonthefinaldiagnosis accordingtotheInternationalStatisticalClassificationofDiseases andRelatedHealthProblems-TenthRevision(ICD-10)code.

Patientswerethusdividedintotwogroups,i.e.thosewitha time-criticalconditionaccordingtoﬁnaldiagnosisandthose with-out.

Atime-critical conditionwas deﬁnedaccordingtoHagiwara et al. [6] and comprised the following diagnoses: myocardial infarction,unstable angina pectoris,transitory ischaemicattack (TIA)/stroke, unconsciousness, sepsis, aortic dissection/rupture, anyformofshock,pulmonaryembolism,heartfailureincluding pulmonaryoedema,bundlebranchblock,cardiacarrest, intoxica-tion,water-electrolyteimbalanceandhigh-energytrauma.

Allcasesthathadanyoftheaboveastheﬁnaldiagnosiswere morecarefullyreviewed,addressingsomevariablesthatwerenot addressedintheremainingpatients.

Prioritisation

Patientswereprioritisedatthedispatchcentreatthreepriority levels.

Level1)Lifethreateningandanambulancedispatchedwithblue lightsandsirens

Level2)Notlifethreatening;canaccept30-minutewaitingtime fortheEMS

Level3)NormalwaitingtimefortheEMS

Patientswereassessed and triagedatthescene bytheEMS clinicianbasedonpatientseverityaccordingtotheRapid Emer-gencyTriageandTreatmentSystem(RETTS).Thissystemisbased onthevitalsignsofdegreeofconsciousness,oxygensaturation, res-piratoryrate,heartrate,bloodpressureandbodytemperaturein combinationwithanESScode.Thelatterdefinesthemodeof com-plaint,i.e.chestpain,dizzinessandsoon.Eachpatientiscategorised intooneoffivecolours(red,orange,yellow,greenandblue)and oneESScodethatdefinethemainsymptom.Redislifethreatening andorangeispotentiallylifethreatening.Bothcolorsindicatethat

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thepatientshouldbemonitoredandseenbyaphysicianattheED assoonaspossible.Yellowandgreenindicatenon-life-threatening conditions,butpatientsneedtobeseenbyaphysicianwithina reasonabletime.

Bluemeansthatalowerlevelofcaremaybemoreappropriate thanEDadmission.Atthetimeofthestudy,thebluelevelwasnot inuseintheEMS.

Dataanalysis

Theresultispresentedasnumbers,percentagesorthemedian with25thand75thpercentiles.Whencontinuousvariablesaswell asordereddata(prioritylevel)werecompared,theMann-Whitney UtestwasusedandFisher’sexacttestfordichotomous/categorical variables.Alltestsaretwo-sidedand p-valuesbelow0.05were regarded asstatistically signiﬁcant.SPSSversion 22 (IBMCorp, Armonk,NY)wasusedfordataprocessingandstatisticalanalysis. Ethicalconsiderations

Thisstudyhasbeenconductedwithintheframeworkofa mas-ter’sdegreeattheUniversityofBorås.AccordingtotheSwedish law,SFS2003:460Thelawofethicalconsiderationsinhuman tri-als,studiesconductedbystudentsarenotjudgedbytheSwedish ethicalreviewboards.However,BoråsUniversityjudgesallits stu-dents’workaccordingtotheHelsinkiDeclaration.Inallanalyses, patientsremainedanonymousand,asaresult,patientintegritywas respected.

Results

Inall,2048patientsfulﬁlledtheinclusioncriteria(primary mis-sionandassessedasdizziness),but161(8%)ofthemwereexcluded forthefollowingreasons:thepatientlefttheEDbeforebeingseen byaphysician(n=71);thepatientwasassessedbyanother care-giver(n=33),thelackofacompleteidentiﬁcationnumber(n=26), thepatientwassenttoanotherhospitaloutsidethecatchmentarea (n=24)andthepatientwasundertheageof16(n=7).

Fromnowon,theresultswillonlydealwiththeremaining1887 patients.Ofthesepatients, 96(5%)hadatime-criticalcondition accordingtotheﬁnaldiagnosis(ICDcode).

Characteristicsofpatientswithdizzinessinrelationtothe ambulancepopulation

Patientswithdizzinesswerealmost10yearsoldercomparedto theoverallambulancepopulation,andhadahigherpercentageof women(58%),wereassessedatthedispatchcentrewithalower prioritylevelandtriagedon-scenetolowerlevelsmorefrequently (Table1).

Characteristicsofallpatientsinrelationtogender

Ofallpatientswithdizziness,58%werewomen.Womenwere somewhatolderthanmenandtheyweregivenalowerpriority thanmenatthedispatchcentre.

The three most frequent dispatch codes were: 1) headache/dizziness (59%), 2) chest pain/heart disease (10%) and3)uncertaininformation/severelysickpatient(10%).

Womenwerealsoassessedtoalowertriagecolour(level)bythe EMSnurse.Amongbothwomenandmen,about80%weretaken tohospitalandabout20%stayedatthescene.Amongthosewho stayedatthescene,44(11%)attendedtheEDwithin72h.Among thosewhoweretransportedtohospital,slightlymorethan70% weretransporteddirectlybyambulance.Intermsofﬁnaldiagnosis

Table1

CharacteristicsofallESS11casesinrelationtoallprimarymissions.

ESS11Dizziness(n= 1887) Primarymissions(n= 58,575) Age-yearsa Median(25th_,75th percentile) 72(55−83) 63(35−80) Gender-n(%)b Women 1087(58.1) 30084(53.4) Men 783(41.9) 26217(46.6) Priorityatdispatch centre-n(%)c Prio1 644(34.2) 30128(51.5) Prio2 1154(61.2) 25861(44.2) Prio3 87(4.6) 2487(4.3)

TriagecolourRETTS -n(%)d Red 24(1.3) 5431(10.5) Orange 422(22.4) 16246(31.4) Yellow 1019(54.0) 21256(41.1) Green 422(22.4) 8826(17.1) Levelofcare-n(%) Tohospital 1493(79.1) 45212(77.2) Stayatthescene 394(20.9) 13363(22.8) Modeoftransport -n(%)e Ambulance 1361(91.2) 42564(94.1) PTS,immobilef ₅₀_(3.3) ₁₀₇₆_(2.4) PTS,seated 49(3.3) 854(1.9) Single-responder unit 17(1.1) 303(0.7) Transportbyown means 16(1.1) 415(0.9)

a₁₇_missing_in_ESS_11;₁₇₇₆_in_primary_missions. b₁₇_missing_in_ESS_11;₂₂₇₄_in_primary_missions.

c _Two_prio₄_cases_excluded_(assessed_as_transport_only_by_dispatch)_in_ESS_11;

99inprimarymissions.

d₆₈₁₆_missing_in_primary_missions. e_Of_patients_transported_to_hospital.

f _PTS:_{non-emergency}_patient_transport_services.

(ICDcode),4%ofwomenand6%ofmenhadatime-criticalcondition (p=0.06)(Table2).

Characteristicsamongwomenandmenwithatime-critical condition

Womenwere10 yearsolderthanmen.Noneofthepatients wasgiventhehighestprioritycolour(red).Fourpercentofwomen andeightpercentofmenwerenotconveyed.Allthesepatients attendedtheEDwithin72h.Amongthosewhoweretakento hospi-tal,96%ofwomenand92%ofmenweretransportedbyambulance (Table3).

Previoushistoryamongpatientswithatime-criticalcondition Themostfrequentpreviouslyknowndiseasesamongpatients withatime-criticalconditionwerehypertension(52%),stroke/TIA (31%),heartdiseaseincludingmyocardialinfarction,angina pec-torisandheartfailure(22%),diabetes(18%),atrialﬁbrillation(18%), cancer(10%)andperipheralarterydisease(1%).

Findingsassociatedwithonsetofsymptomsinthecritical conditions

Themostfrequentﬁndingsassociatedwithonsetofsymptoms intimecriticalconditionswere1)anacuteonset(63%),2)nausea, vomiting(61%),3)thepatienthadatendencytobleedorwason treatmentwithanticoagulants(25%),4)ahistoryofheadtrauma (16%),5)suddenonsetofheadache(11%)and6)lossof conscious-ness(10%).

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Table2

CharacteristicsofallESS11casesinrelationtogender.

Gender Women(n=1087) Men(n=783) P Age-years Median(25th_,75th percentile) 73(56−84) 71(55−81) 0.025 Priorityatdispatch centre-n(%)a 0.001 Prio1 334(30.8) 302(38.6) Prio2 698(64.3) 448(57.2) Prio3 53(4.9) 33(4.2)

TriagecolourRETTS -n(%) 0.002 Red 11(1.0) 13(1.7) Orange 224(20.6) 195(24.9) Yellow 587(54.0) 423(54.0) Green 265(24.4) 152(19.4) Levelofcare-n(%) 0.170 Tohospital 849(78.1) 632(80.7) Stayatthescene 238(21.9) 151(19.3) Seekmedicaladvice

within72h.-n(%)b 29(12.2) 15(9.9) 0.517 Modeoftransport -n(%)c 0.605 Ambulance 764(90.0) 584(92.4) PTS,immobiled ₃₃_(3.9) ₁₇_(2.7) PTS,seated 32(3.8) 18(2.8) Single-responder unit 8(0.9) 9(1.4) Transportbyown means 12(1.4) 4(0.6) Typeofcondition-n(%) Non-timecritical 1040(95.7) 734(93.7) 0.062 Timecritical 47(4.3) 49(6.3)

a_Two_prio₄_cases_excluded_(assessed_as_transport_only_by_dispatch). b _Of_patients_initially_assessed_to_stay_at_the_scene.

c _Of_patients_transported_to_hospital.

d _PTS:_{non-emergency}_patient_transport_services.

Table3

Characteristicsofpatientswithatime-criticalconditioninrelationtogender.

Gender Women(n=47) Men(n=49) P Age-years Median(25th,75th percentile) 81(70−86) 71(63−83) 0.010 Priorityatdispatch centre-n(%) 0.058 Prio1 16(34.0) 26(53.1) Prio2 29(61.7) 22(44.9) Prio3 2(4.3) 1(2.0) TriagecolourRETTS

-n(%) 0.074 Red 0(0) 0(0) Orange 16(34.0) 24(49.0) Yellow 22(46.8) 21(42.9) Green 9(19.1) 4(8.2) Levelofcare-n(%) 0.432 Tohospital 45(95.7) 45(91.8) Stayatthescene 2(4.3) 4(8.2) Seekmedicaladvice

within72h.-n(%)a 2(100) 4(100) Modeoftransport -n(%)b 0.409 Ambulance 41(91.1) 42(93.3) PTS,immobilec ₁_(2.2) ₁_(2.2) PTS,seated 2(4.4) 0(0) Single-responder unit 0(0) 2(4.4) Transportbyown means 1(2.2) 0(0)

a_Of_patients_initially_assessed_to_stay_at_the_scene. b _Of_patients_transported_to_hospital.

c _PTS:_{non-emergency}_patient_transport_services.

Fig.1. MostfrequentICD10diagnosisforESS11patientswithatimecritical diag-nosis.

Fig.2.MostfrequentICD10diagnosisforESS11patientswithoutatimecritical diagnosis.

Comparisonbetweentime-criticalandnon-time-critical conditionsintermsofageandvitalparameters

Patientswithatime-criticalconditionwereolder,hadslightly lower oxygen saturation and had higher blood pressure than patientswithoutatime-criticalcondition(Table4).

Finaldiagnosis

Inall,therewere230differentICDcodes.Amongthepatients witha time-criticalcondition,a cerebrovasculardiseasewasby far the most frequent ﬁnal diagnosis (Fig. 1), whereas, among thepatientswithanon-time-criticalcondition,dizziness/giddiness wasthemostfrequentﬁnaldiagnosis(Fig.2).

Discussion

Overallresults

Inthispilotstudy,wefoundthat3.5%ofprimaryEMSmissions wereassessedbythearrivingEMScrewasbeingcausedby symp-tomsofdizziness.Amongthesepatients,ﬁvepercenthadaﬁnal diagnosisequivalenttoatime-criticalcondition.Themajorityof thesepatientshadacerebrovasculardisease.Comparedtothe aver-agepatientwhocallsforEMS,thepatientwithdizzinessappears tobeolderandisgivenalowerprioritybytheEMScrew.

Theﬁndingthat3.5%ofprimaryEMSmissionsareassessedby theEMScrewasdizzinessisinagreementwithareportbyHjälte

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Table4

Acomparisonbetweenpatients(ESS11)withandwithoutatime-criticalconditionwithregardtoageandvitalparameters.

Typeofcondition Time-criticalcondition(n=96) Withouttime-criticalcondition(n=1774) P Age-yeara

Median(25th,75thpercentile) 78(66−85) 72(54−82) 0.001

Vitalsigns-Median(25th,75thpercentile)

Respiratoryrate/minb ₁₆_(16−18) ₁₆_(16−18) _0.863

Oxygensaturation-%c ₉₈_(96−98) ₉₈_(97−99) _0.026

Systolicbloodpressure-mm/Hgd ₁₆₀_(140−174) ₁₄₀_(125−160) _<0.001

Diastolicbloodpressure-mm/Hge ₉₀_(75−100) ₈₀_(75−90) _0.008

Heartrate/minf ₇₈_(70−90) ₈₀_(70−90) _0.603 Temperature◦_Cg _36.6_{(36.1−36.9)} _36.7_{(36.3−37.0)} _0.093 a₁₇_missing. b₉₆_missing. c ₆₈_missing. d ₇₀_missing. e₁₉₅_missing. f ₆₆_missing. g₁₁₇_missing.

etal.[7],whofoundthat,amongallcallstothedispatchcentre, threepercentwereduetodizziness.Furthermore,thisﬁndingis ingoodagreementwithapreviousreportbyNewman-Tokeretal. [8],whoreportedthat,amongconsecutiveEDadmissions,about 3%arecausedbydizziness.

Wefoundthatfivepercentofpatientswithdizzinesshada time-criticalconditionwherethevastmajorityhadacerebrovascular disease.Thisisnewinformation.However,itisingoodagreement witha studyintheEDbyKerberetal.[9],where itwasfound thatthreepercentofpatientswithdizzinesshadanunderlying stroke.Doijirietal.[10]foundthat,amongpatientswhowere hos-pitaliseddue toisolated dizziness,11%had astrokewhichwas mainlylocatedinthecerebellum.Similarfindingsweremadeby Navietal.[11]andLjunggrenetal.[12],whobothreportedthat fivepercentofadmissionstotheEDduetodizzinesswerecaused byacerebrovasculardisease.

The next time-critical condition in order of frequency was electrolyteimbalance.However,onlyﬁveof1887patients(0.3%) fulﬁlledthiscriterion.InthestudybyNavietal.[11],twopercent hadanelectrolyteimbalance.

Amongthepatientswithanon-time-criticalcondition,alarge proportionhadanICDcodeequivalenttoaﬁnaldiagnosisof dizzi-ness/giddiness.Thishighlightsthefactthatmanypatientsdidnot receiveanadequateexplanationoftheaetiologybehindtheir com-plaints.

Welookedforcharacteristicsamongthepatientswitha time-criticalcondition.Averylargeproportionofthesepatientseither hadanacuteonsetofthedizzinessorsimultaneouslysufferedfrom nausea,vomiting.Unfortunately,wedonotknowthe correspond-ingﬁgureforpatientswithoutatime-criticalcondition.Tarnutzer etal.[13]reportedthatpatientswithsymptomsofdizzinesswhich wascaused bya strokemore frequentlyhad an acuteonset of symptomsthanpatientswithdizzinessduetovestibular neuroni-tis.Simultaneoussymptomsofnauseaandvomitinghavealsobeen reportedbyothersasfrequentlyoccurringamongpatientswith dizzinesscausedbyastroke[9,11].However,innoneofthese stud-ieswastheriskofthesesymptomsmorefrequentamongpatients withstrokeascomparedwithnon-time-criticalconditions.

Thehypothesisthatnauseavomitingmaybeawarningsignfor atime-criticalconditionamongpatientswithvertigogets some supportfromthesituationinothertimecriticalconditions.Thus, amongpatientswithacutechestpainassessedbyEMS,wasthe presence of nausea, vomiting shown to be associated with an increasedriskofanunderlyingacutemyocardialinfarction[14].

Patientswithatime-criticalconditionwereolderthanpatients withoutone.Thisisinagreementwiththeﬁndingsreportedby Navietal.[11].Wealsofoundthatpatientswithatime-critical

conditionmorefrequentlyhadanelevationoftheirsystolicand diastolicbloodpressure,ascomparedwithnon-time-critical con-ditions.ThisisinagreementwiththeﬁndingsreportedbyKerber etal.[9]andmaybeexplainedbythefactthatanelevationofblood pressureiscommonintheacutephaseofastroke[15–18].

Intermsofprevioushistory, ahighrateofhypertensionand TIA/strokewasfoundamongpatientswithatime-criticalcondition. Arelativelyhighproportionofthepatientswithsuchacondition hadaprevioushistoryofvariousheartdiseasesincludingatrial ﬁb-rillationwhichisawell-knownriskfactorforstroke[20].Ahistory ofdiabetes,whichisanotherriskfactorforstroke[21]wasalso rel-ativelycommonamongthesepatients.Thus,informationfromthe patient’scomorbiditymaygiveimportantinformationregarding theriskofatimecriticalcondition.Such ahypothesisgets sup-portfromNavietal.[11],whoreportedahigherrateofsomeof thesepreviousdiseasesamongpatientswhohaddizzinesscaused byastrokethanamongpatientswhohaddizzinesscausedbyother diseases.

Theremaythereforebesomedifferencesintermsoftheinitial clinicalpicturewhen patientswithdizziness causedbya time-critical conditionare compared withthose withoutone. In the future,thesedifferencescouldbeusedinamoresystematic man-nertocreateadecisionsupporttoolfortheassessmentofpatients withdizzinessbytheEMScrewintheprehospitalsetting.

Thus,onemayspeculatethat adecisionsupporttoolfor the EMScrewtriagingpatientswithvertigomaybebasedonspeciﬁc informationregardingthepatient’sage,previoushistorywithfocus oncardiovasculardisease,thetypeofacuteonsetofsymptomsand clinicalﬁndingsonadmissionoftheEMScrew.Theaimofsuch atoolshouldprimarilybetoidentifypatientswithatimecritical etiology.Asecondaryaimmaybetoidentifypatientswhodonot needtobetransportedbyEMStoahospitalbutcouldinsteadbe handledatalowerlevelofcare.

Noneofthepatientswithatime-criticalconditionreceivedthe highestpriority(red)whenassessedbytheEMScrewaccordingto RETTS.Thisisbestexplainedbythefactthatthereisnoredlevel basedontheESScodefordizziness.So,inordertobetriagedto levelred,vitalsignsmustbelifethreateningandadeviationofthis kindobviouslydidnotoccur.

Strengthsandlimitations

Thisisacohort,whichrepresentsconsecutivepatientsfroma singleEMSsystemfromanurbanarea.Forthisreason,ourdata cannotbeextrapolatedtoruralareaswithanydegreeofcertainty. Furthermore,thisisaretrospective,observationalstudywithall itsweaknesses,includingalargeproportionofcaseswith miss-inginformation.Finally,questionsrelatingtodifferentaspectsof

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symptomsandprevioushistorywereonlyaddressedincaseswith atime-criticalcondition.

Conclusion

Amongprimary missionsby theEMS, 3.5%of patientswere assessedassufferingfromdizziness.Ofthem,5%hadatime-critical conditionandthemajorityofthesepatientshadacerebrovascular disease.Furtherstudiesarerequiredtodevelopinstrumentsthat canhelptoidentifytime-criticalconditionsatanearlystageamong patientswhocallfortheEMSduetodizziness.

Authorship

NP,VG,JHandCAplannedthestudyanddevelopedtheresearch design.NP,VGandCMplannedandcarriedoutthedatacollection. JHwrotetheﬁrstdraftandJH,MA,KJ,CMandCAwas responsi-bleforrevisions.Allauthorsdiscussedand commentedondraft versionsandapprovedtheﬁnalversion.

Thestudywasacceptedbytheresearchethicscounseloratthe UniversityofBorås,Sweden,andconductedinagreementwiththe ethicalreferencesoftheSwedishResearchCouncil.

Funding

Thisresearchdidnotreceiveanyspeciﬁcgrantfromfunding agenciesinthepublic,commercial,ornot-for-proﬁtsectors.

Conﬂictofinterest

Allthesigningauthorsmeettherequirementsforauthorship andtheyhavenoconﬂictsofinterest.

References

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