Urgent Care Section 34

Department ofEmergencyMedicine Department ofEmergencyMedicine EMERGENCY MEDICINE Eastern Virginia Medical School Donald ByarsII,MD,FACEP URGENT CARE Michael McDavit,MD Assistant Professor Norfolk, Virginia

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JULY 2009 Need Transient diagnosis and managementof suspectedTIA. and outlineanappropriately aggressiveapproachto authors exploretherelationship betweenTIAandstroke though aTIAprecedes roughlyoneinfourstrokes.The were notfollowedup foratleastamonth—even presentations consistentwithtransientischemic attack In arecentstudy, almostathirdofprimarycare Attack:

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© 2009 Steve Oh/Phottake Urgent Care Section 35

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Most TIAs resolve within one hour and if they do not, there is less than a 15% chance that they will resolve within 24 hours. >> TRANSIENT ISCHEMIC ATTACK ATTACK ISCHEMIC TRANSIENT JULY 2009 JULY in 2002, states that “a TIA Currently, the Currently, 5 Ideally, then, each patient would undergo then, each patient Ideally, 4 This has led some 5 Diffusion-weighted MRI measures the diffu- Diffusion-weighted MRI measures The notion of a 24-hour time frame has also The notion of a 24-hour advanced imaging such as CT or MRI to better advanced imaging such as CT or assess for any signs of . to differenti- sion of water and has been shown of symptom ate TIA from within 6 hours has also however, onset. This same technology, In a recent served to cloud the definition of TIA. a clinical diagnosis of TIA 87 patients with study, but negative CT underwent diffusion-weighted MRI. Thirty-six (41%) had evidence of infarc- tion. authorities to classify this subgroup of patients as having “transient symp- toms associated with in- farction.” presence of new infarction does not in- fluence management of patients with transient symptoms, so the distinction may be more aca- demic than clinical. Institutes of Health, is arbitrary and originated in and originated of Health, is arbitrary Institutes advanced imaging and 1960s, when the 1950s put, it was thought available. Simply was not less than 24 hours were that symptoms lasting infarction and permanent im- unlikely to cause most TIAs resolve within one pairment. In fact, not, there is less than a 15% hour and if they do will resolve within 24 hours. chance that they ASSESSING THE PATIENT can Clinical symptoms of TIA, which vary widely, be sorted into three groups according to whether Journal of Medicine dysfunction is a brief episode of neurologic with caused by focal brain or retinal , less than clinical symptoms typically lasting and without evidence of acute infarc- one hour, tion.” undergone scrutiny with the advent of new im- undergone scrutiny such as CT and MRI. Multiple aging technology that significant numbers studies have shown had been diagnosed with TIA of patients who injuries. actually had permanent ischemic brain tissue-based definition has Therefore, a newer, distinction been proposed that emphasizes the (stroke). between ischemia (TIA) and infarction This definition, proposed in the

4 Approx- 1 This article 3 . Embolic TIAs transient ischemic The management of The management lacunes 2 is still a work in progress. The original ust as angina is often the first sign of an is often the ust as angina infarction, a acute myocardial impending is often the ischemic attack (TIA) transient stroke—the lead- first sign of an imminent Historically, physicians have not been aggres- physicians Historically, The definition of the term

This time limit, adopted in 1975 by the National ischemic stroke is primarily supportive and ischemic stroke is disability is largely predeter- or the degree of tissue plasminogen activator mined, although the course of the event. can sometimes reverse opportunity to recognize and That means the attack successfully manage transient ischemic have to spare may be the best chance physicians or loss of life a given patient irreversible harm from stroke. reported sive in the workup of TIA. A recent study primary care that 31% of patients presenting to had no fur- with symptoms consistent with TIA ther workup within the first month. will discuss how to ensure that patients present- will discuss how to ensure that patients and timely ing to urgent care get the thorough of recurrent workup necessary to reduce the risk stroke. TIA and permanent and debilitating the United States. cause of death in of disability and the third leading ing cause

DRAWING THE LINE DRAWING attack Ischemic stroke and transient ischemic Risk factors for share the same pathophysiology. and obesity, both include hypertension, smoking, of stenosis diabetes. Either may be due to areas in major vessels such as the internal carotid ar- or posterior cerebral middle, tery or the anterior, If the or in the vertebral or basilar artery. artery, stenosis is severe enough and collateral flow is Stenosis of the impaired, TIA or stroke may occur. tiny penetrating arteries, usually from longstand- ing hypertension or diabetes, can similarly cause TIA or small , called J imately 795,000 Americans experience a new or imately 795,000 Americans year. recurrent stroke each or classic definition states that a TIA is a focal neurologic deficit caused by focal brain ischemia that completely resolves in less than 24 hours. and strokes generally arise from cardiac pathol- ogy but may also result from primary vascular disease such as atherosclerosis. attack www.emedmag.com Urgent Care Section 36

>> TRANSIENT ISCHEMICATTACK that mimicTIA. detecting otherproblems CT ismostusefulfor

EMERGENCY MEDICINE FAST rologic function. ECGismostusefulin detecting identified becausetheycan causealteredneu- glucose andotherelectrolyte levelsneedtobe cardiac enzymes,andhead CT. Derangementsin complete bloodcount,basic metabolicpanel, the extentofimpairment,ruleoutpotentialmim- standardized systematicevaluationtodetermine motor orsensorydeficits. deep circulation found inisolation. or stroke,theyappearinclustersandarerarely that whenthesesymptomsarearesultofTIA dysarthria anddysphagia.Itshouldbenoted leading todiplopia.Othersymptomsinclude in theoccipitallobecancausegazedisturbances, , ,nausea,andvomiting.Disruptions the posteriorsystem,commonsymptomsinclude as theposteriorcerebralartery. InTIAsinvolving through thebasilarandvertebralarteriesaswell the occipitallobes,,andcerebellum fected), neglect,andhomonymoushemianopia. aphasia (whenthedominanthemisphereisaf- and upperextremity. Othersymptomsinclude same symptomsinvolvethecontralateralface problem isinthemiddlecerebralartery, these numbness inthelowerextremities.When toms includeunilateralweakness,paralysis,or rior cerebralarteryisinvolved,commonsymp- rather thancompleteblindness.Whentheante- that patientscansimplyhaveavisualfielddeficit the ophthalmicartery. Itshouldbenoted,though, rary monocularblindnesscausedbyocclusionof manifestation ofTIAisamaurosisfugax,tempo- of thecerebralhemispheres.Theclassicocular bral) andsuppliesbloodtotheretinasmost (ophthalmic, anteriorcerebral,andmiddlecere- left internalcarotidarteriesandtheirbranches deep circulation. there isischemiaintheanterior, posterior, or The Patients withsuspectedTIAmustundergoa Lacunar TIAsarecausedbyischemiainthe The

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JULY 2009 signs, pulseoximetry, ECG, cludes areviewofvital are required;thelatterin- history andphysicalexam possible causes.Complete ics ofTIA,andelucidate involvestherightand suppliesbloodto ing withTIA. determine whethertoadmitapatientpresent- calculates 2-daystrokerisktohelpclinicians TIA. topic ontheshort-termriskofstrokefollowing leagues recentlypublishedacriticallyappraised workup andtreatmentregimen.Shahcol- ship underscoretheimportanceofanexpedited by TIA.Severalstudiesanalyzingthisrelation- In general,about25%ofstrokesarepreceded PREDICTIVE RELATIONSHIP disabled and21%died. suffered asubsequentstrokeweresignificantly included datashowingthat64%ofthosewho 30-day riskwas5%to18%.Oneofthestudies to 10%,the7-dayriskwas4%13%,and combined average2-dayriskofstrokewas1.5% who wereseeninprimarycaresettings.The other studiesincludedlargenumbersofpatients ing solelytoemergencydepartments,whilethe spective studieswerebasedonpatientspresent- rospective—were selected.Two ofthefivepro- deficit lasting morethan60minutesis given2 points. Fordurationofsymptoms, aneurologic and allotherclinicalpresentations aregiven0 ness isgiven2points,speech disturbance1point, 1 point.Underclinicalfeatures, unilateralweak- 140 oradiastolicreadinggreater than90isgiven blood pressure,asystolicreadinggreaterthan betes mellitus.Ageover60isgiven1point.For duration ofsymptoms,and(D)diagnosisdia- age, (B)bloodpressure,(C)clinicalfeatures,(D) California score.Pointsaregivenbasedon(A) cal predictionrules:theABCDscoreand cardioembolic sourceissuspected. raphy withtestingforrighttoleftshuntingifa as transthoracicortransesophagealechocardiog- raphy orDopplerultrasound,ifavailable,aswell carotid arteryimagingusingCTorMRangiog- National StrokeAssociationalsorecommends tect ischemiclesionswithinminutesofonset.The Diffusion-weighted MRI,asnotedearlier, cande- subdural, epidural,orsubarachnoidhemorrhage. such asabraintumor, aswellforidentifyinga ful fordetectingotherproblemsthatmimicTIA, cause itcausesembolicevents.CTismostuse- ,whichisariskfactorforTIAbe- The ABCD 7 Eightstudies—fiveprospective,threeret- 8 2 Itisbasedondatafromtwoclini- predictionruleisanewtoolthat 7 www.emedmag.com 6

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TRANSIENT ISCHEMIC ATTACK ISCHEMIC TRANSIENT In this study, patients with In this study, JULY 2009 JULY 9 POSTDIAGNOSTIC MANAGEMENT a recent trial suggests that a spe- Interestingly, emergencycial TIA observation unit within an for thesedepartment may do as well or better admission, apatients compared with hospital by urgentconcept that may merit consideration care facilities as well. patients with their first presumed TIA if they pres- TIA if they their first presumed patients with so-called vulnerable 24 to 48 hours—the ent within definitive secondary is to facilitate period. This use of lytic therapy if symp- prevention and the are discharged must be Patients who toms recur. the need to return if symptomsfully informed of to admit based specifically Other reasons recur. include crescendo TIAs, dura- on these guidelines known ca- greater than 1 hour, tion of symptoms 50% or worse, atrial fibrillationrotid stenosis of potential, or known hyper- or other cardioembolic coagulable state. TIA who had normal CT, ECG, and lab test re- TIA who had normal CT, were eithersults and no known embolic source

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8 Admission should be considered for all Admission should be considered for 6 Certainly, a score of 5 or more should prompt a score of 5 or more Certainly, The National Stroke Association’s recent The National Stroke Association’s

the physician to admit for expedited care. It is the physician to though, that the ABCD important to remember, points; between 10 and 59 minutes, 1 point; and minutes, 1 point; 10 and 59 points; between An points are given. 10 minutes, no if less than dia- if the patient has point is assigned additional of 3 or less indicates there betes. A total score stroke within the next 2 days. is a 1% chance of 6-7 predict a 2-day stroke risk Scores of 4-5 and respectively. of 4.1% and 8.1%, score is simply one part of the evaluation and score is simply one sole determinant of admission must not be the high-risk groups must be or discharge. Certain these include admitted regardless of their score; type of an- patients with recurrent TIA during any those with TIA tiplatelet or therapy, atrial fibrilla- of presumed cardiac origin (such as tion), and those with crescendo TIAs. of TIAguideline update for the management in theplaces increased emphasis on speed workup. www.emedmag.com Urgent Care Section 38

>> TRANSIENT ISCHEMICATTACK than 120/80mmHg. reduced toagoalofless blood pressureshouldbe period of24to36hours, After abriefwaiting

EMERGENCY MEDICINE FAST scribed withatargetinternationalnormalizedra- with atrialfibrillation,warfarinshouldbepre- assured, otherstepsneedtobetaken.Forpatients dipyridamole combinationtwicedaily. clopidogrel 75mgdaily, ora 25/200mgaspirin/ can beintheformofaspirin50to325mgdaily, tion, antiplatelettherapyshouldbeinitiated.This ensured. Unlessthereisaspecificcontraindica- a goal of less than 120/80 mm Hg. This can be a goaloflessthan120/80mmHg.Thiscanbe to 36hours,bloodpressureshouldbereduced use ofastatin.Afterbriefwaitingperiod24 should befollowed. or isotherwisedischarged,severalguidelines for TIApatients.If,however, apatientwillnotstay clinical events. return visits,subsequentstrokes,andothermajor Three-month follow-uprevealedsimilarratesof more frequentlyintheobservationunitgroup. aging andechocardiographywerecompleted patients. Itshouldalsobenotedthatcarotidim- for observedpatientsversus$1547admitted money aswell.Mediancostperpatientwas$890 hours versus61.2forinpatients. unit patients,withamedianlengthofstay25.6 less fortheemergencydepartmentobservation gered admission.Lengthofstaywassignificantly protocol, 15%hadapositivefindingthattrig- toring. Ofthepatientsinspecialdiagnostic trasound, echocardiography, andcardiacmoni- exams, neurologicconsult,carotidDopplerul- protocol. Eachgroupunderwentserialclinical admitted orplaced In rural practice or where follow-up cannot be In ruralpracticeorwherefollow-upcannotbe Clearly, observationisthesafest management Having aTIAobservationunitseemstosave

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JULY 2009 in anaccelerateddiagnostic 6 Closefollow-upshouldbe blood pressure control and blood pressurecontroland ventions shouldinclude rin initiation.Otherinter- the firstfewdaysofwarfa- of hypercoagulabilitywithin due tothehypotheticalrisk also beconsideredinitially tio of2.5.Enoxaparinshould or hormonetherapy. risk ofbloodclotting,suchasbirthcontrolpills pathomimetic drugsorthatincreasethe should becautionedagainsttheuseofanysym- ies inthosewhomayhavesleepapnea.Patients patients, and alcoholcessation,glucosecontrolfordiabetic has beenshowntoreducerecurrentstrokerisk. for AfricanAmericans.Atorvastatin80mgdaily with heartdiseaseandcalciumchannelblockers Second-line agentsincludebeta-blockersforthose ACE inhibitorsorangiotensinreceptorblockers. done withfirst-lineagentssuchasthiazidesand . Ross MA,ComptonS,MedadoP,9. etal.Anemergencydepart- Johnston SC,RothwellPM,Nguyen-HuynhMN,etal.Validation 8. Shah KH,KlecknerK,Edlow JA.Short-termprognosisofstroke 7. . Johnston SC,Nguyen-HuynhMN,SchwarzME,etal.National 6. Ay H,KoroshetzWJ,BennerT, etal.Transient5. ischemicattack . 4. Albers GW, CaplanLR,EastonJD,etal.Transient isch- Goldstein LB,BianJ,SamsaGP,3. etal.Newtransientischemic 2.Lloyd-Jones D,AdamsR,CarnethonM,etal.Heartdisease Shah KH,EdlowJA.Transient1. ischemicattack:review forthe REFERENCES n osqecso toe ing consequencesofstroke. and interventionsthatcanpreventthedevastat- sion offersthebenefitsofexpediteddiagnostics subgroup, anobservationunitorhospitaladmis- close follow-upmaybeappropriateinacertain diagnosed withTIA.Althoughdischarge Efforts shouldalsobemadetowardsmoking We suggesttheliberaladmissionofpatients emic attack:arandomizedcontrolledtrial. ment diagnosticprotocolforpatientswithtransientisch- transient ischaemicattack. and refinementofscorestopredictveryearlystrokeriskafter transient ischemicattack. among patientsdiagnosedintheemergencydepartmentwitha 2007;50(2):109-119. ischemic attacks. Stroke Associationguidelinesforthemanagementoftransient (5):679-686. with infarction:auniquesyndrome? 2002;347(21):1713-1716. emic attack—proposalforanewdefinition. sicians. attack andstroke:outpatientmanagementbyprimarycarephy- Subcommittee. Heart AssociationStatisticsCommitteeandStroke and strokestatistics—2009update:areportfromtheAmerican emergency physician.

Arch InternMed weight loss,andreferralforsleepstud- Circulation Ann Neurol Ann EmergMed 6 . 2000;160:2941-2946. Ann EmergMed . 2009;119(3):e21-181. Lancet . 2006;60(3):301-313. . 2007;369(9558):283-292. . 2004;43(5):592-604. www.emedmag.com Ann Neurol . 2008;51(3):316-323. Ann EmergMed N EnglJMed . 2005;57 Q . .