Stroke in the emergency department

Transcription

1 Cambridge Uiversity Press Acute Stroke Care: A Maual from the Uiversity of Texas-Housto Stroke Team Ke Uchio, Jeifer K. Pary ad James C. Grotta More iformatio 1 Stroke i the emergecy departmet Stroke is the most commo eurological emergecy, ad, because effective treatmet is available that must be started withi miutes, most acute eurological presetatios should be assumed to be a stroke util prove otherwise by history, exam, or radiographic testig. Ufortuately, there is ot a quick ad easy laboratory or cliical test to determie for sure that the patiet lyig i frot of you is havig a stroke, so a accurate history ad exam are essetial. Is this a stroke? DEFINITION The term stroke usually refers either to a cerebral ifarctio or to o-traumatic cerebral hemorrhage. Depedig o the populatio you are seeig (ethicity, age, comorbidities) the ratio of ifarcts to hemorrhages is about 4:1. As will be described i more detail i Chapter 3, cerebral ifarcts ca be caused by a umber of pathological processes, but all ed with a occlusio of a cerebral artery or vei. If the arterial occlusio results i a reductio of blood flow isufficiet to cause death of tissue (ifarctio), it is termed ischemia. 1 Cambridge Uiversity Press

2 Cambridge Uiversity Press Acute Stroke Care: A Maual from the Uiversity of Texas-Housto Stroke Team Ke Uchio, Jeifer K. Pary ad James C. Grotta More iformatio 2 Stroke i the emergecy departmet As will be described i more detail i Chapter 8, otraumatic cerebral hemorrhages are caused by a umber of pathological processes which all lead to bleedig ito the brai parechyma ad vetricles. Bleedig ito the subarachoid space (Chapter 9) is usually caused by a ruptured aeurysm or vascular malformatio. Other types of brai bleedig, for example ito the subdural or epidural space, are usually traumatic ad are ot cosidered i this book. PRESENTATION Whe takig the history, the most characteristic aspect of a cerebral ifarct or hemorrhage is the abrupt oset, so be sure to get the exact flavor of the oset. It is also imperative to determie as precisely as possible the time of oset. The symptoms most ofte stay the same or improve somewhat over the ext hours, but may worse i a smooth or stutterig course. Ischemic strokes (but ot hemorrhages) may rapidly resolve, but eve if they resolve completely, they may recur after miutes to hours. The secod characteristic historical aspect of cerebral ifarcts is that the symptoms will usually fit the distributio of a sigle vascular territory. This is also the most importat characteristic of the eurological exam i a patiet with a ifarct. Therefore, patiets with a ifarct will preset with symptoms ad sigs i the middle, aterior, or posterior cerebral arteries, a peetratig artery (producig a lacuar sydrome), or the vertebral or basilar artery (see below). Parechymal hemorrhages also occur i characteristic locatios, ad usually share the same symptom complex ad sigs as cerebral ifarcts except that early decrease i level of cosciousess, ausea ad vomitig, headache, ad accelerated hypertesio are more commo with hemorrhages. Cambridge Uiversity Press

3 Cambridge Uiversity Press Acute Stroke Care: A Maual from the Uiversity of Texas-Housto Stroke Team Ke Uchio, Jeifer K. Pary ad James C. Grotta More iformatio Is this a stroke? 3 Subarachoid hemorrhages classically preset as a burstig very severe headache ( the worst headache of my life ), ad are ofte accompaied by stiff eck, decreased cosciousess, ausea ad vomitig. Focal eurological sigs are ofte abset; if preset, they usually sigify associated bleedig ito the parechyma. Sigs ad symptoms characteristic of the various arterial territories. Middle cerebral cotralateral loss of stregth ad sesatio i the face, arm, ad to a lesser extet leg. Aphasia if domiat hemisphere, eglect if o-domiat.. Aterior cerebral cotralateral loss of stregth ad sesatio i the leg ad to a lesser extet arm.. Posterior cerebral cotralateral visual field deficit. Possibly cofusio ad aphasia if domiat hemisphere.. Peetratig (lacuar sydrome) cotralateral weakess or sesory loss (usually ot both) i face, arm, ad leg. No aphasia, eglect, or visual loss. Possibly ataxia, dysarthria.. Vertebral (or posterior iferior cerebellar) trucal ataxia, dysarthria, dysphagia, ipsilateral sesory loss o the face, ad cotralateral sesory loss below the eck.. Basilar various combiatios of limb ataxia, dysarthria, dysphagia, facial ad limb weakess ad sesory loss (may be bilateral), pupillary asymmetry, discojugate gaze, visual field loss, decreased resposiveess. DIAGNOSIS There is curretly o 100% sesitive ad specific test for cerebral ifarctio i the emergecy departmet, so that the Cambridge Uiversity Press

4 Cambridge Uiversity Press Acute Stroke Care: A Maual from the Uiversity of Texas-Housto Stroke Team Ke Uchio, Jeifer K. Pary ad James C. Grotta More iformatio 4 Stroke i the emergecy departmet diagosis is usually made o the basis of a characteristic history, exam, presece of comorbidities, ad the absece of seizures or other stroke mimics. CT scaig is usually egative i the first three hours, or shows oly subtle sigs that have low iter-observer reliability. If available, MR imagig, or detectio of a occluded artery by trascraial Doppler or arteriography (by CT, MRI or itra-arterial catheterizatio), ca be cofirmatory. Parechymal or subarachoid hemorrhage, o the other had, ca be reliably detected by emerget CT scaig. STROKE MIMICS All of the followig may preset similarly to a stroke. I all cases, the distictio ca be made by a emerget MRI sca, which will show abormal diffusio-weighted sigal i most stroke cases, but ot i mimics.. Seizures. If a seizure has a focal oset i the brai, the patiet may be left with weakess, umbess, speech, or visio problems for a period of time (usually less tha 24 hours) after the seizure. Ulike the typical cerebral ifarct, focal deficits after a seizure are ofte accompaied by lethargy ad have a resolvig course, but if the patiet has had a seizure accompayig a stroke it is impossible to kow for sure how much of the deficit the patiet displays is due to each. This is why patiets with seizures at oset are usually excluded from cliical trials of ew stroke therapies.. Migraie. Patiets may have uilateral weakess or umbess, visual chages, or speech disturbaces associated with a migraie headache ( complicated or complex migraie). Also, patiets with complicated migraie are at higher risk for stroke. I tryig to make the distictio Cambridge Uiversity Press

5 Cambridge Uiversity Press Acute Stroke Care: A Maual from the Uiversity of Texas-Housto Stroke Team Ke Uchio, Jeifer K. Pary ad James C. Grotta More iformatio Is this a stroke? 5 betwee complicated migraie ad stroke, it is importat to remember that because of the high prevalece of both migraie ad stroke i the geeral populatio, it is dagerous to attribute the patiet s deficit to migraie just because the patiet has a migraie history. The best rule of thumb is ot to make the diagosis of complicated migraie or migraious stroke uless the patiet has a history of previous complicated migraie evets similar to the deficit displayed i the emergecy departmet.. Sycope. This is usually due to hypotesio or a cardiac arrhythmia. Stroke rarely presets with sycope aloe. Patiets with vertebrobasilar isufficiecy may have sycope, but there are usually other braistem or cerebellar fidigs if sycope is part of the stroke presetatio.. Hypoglycemia. Patiets with low blood sugar may have symptoms that exactly mimic a stroke. The importat thig is to check the blood sugar ad, if low, correct it. If the symptoms do ot resolve with correctio of the hypoglycemia, the symptoms are probably from a stroke.. Metabolic ecephalopathy. Patiets may have cofusio, slurred speech, or rarely aphasia with this coditio. They usually do ot have other promiet focal fidigs.. Drug overdose. Similar to metabolic ecephalopathy.. Cetral ervous system tumor. The locatio of the tumor would determie the type of sigs ad symptoms see. A tumor, ulike a stroke, usually does ot preset with sudde focal fidigs, uless accompaied by a seizure (see above).. Herpes simplex ecephalitis (HSE). This ifectio teds predomiatly to affect the temporal lobes, so patiets may have sigs of aphasia, hemiparesis or visual-field cuts. Oset ca be rapid ad i its early stages may mimic a stroke, but fever, Cambridge Uiversity Press

6 Cambridge Uiversity Press Acute Stroke Care: A Maual from the Uiversity of Texas-Housto Stroke Team Ke Uchio, Jeifer K. Pary ad James C. Grotta More iformatio 6 Stroke i the emergecy departmet CSF pleocytosis, seizures ad decreased level of cosciousess are more promiet with HSE.. Subdural hematoma. Depedig o the locatio, this may cause cotralateral weakess or umbess that may mimic a stroke. A CT sca ca make this diagosis, but the subdural, if small, may be subtle.. Peripheral compressio europathy. This may cause weakess or umbess i a particular peripheral erve distributio ad is usually ot sudde i oset.. Bell s palsy (peripheral seveth erve palsy). The importat poit here is that the forehead ad eye closure are weak o the same side. Oe ca have a stroke ivolvig the pos ad produce a peripheral seveth erve palsy, but usually there are other sigs ad symptoms such as weakess, a gaze palsy, or ipsilateral sixth erve palsy.. Beig paroxysmal positioal vertigo (BPPV). This may cause vertigo, ausea, vomitig, ad a sese of imbalace, usually with turig of the head i oe directio. This characteristic sydrome is due to labyrithie dysfuctio ad ot stroke. However, as with sycope, the presece of ay braistem or cerebellar sigs should alert oe to the possibility of a stroke.. Coversio disorder. Patiets may develop eurological sigs or symptoms of weakess, umbess, or trouble talkig that are maifestatios of stress or a psychiatric illess. Always assume that your patiet has a true eurologic illess first. What type of stroke? As discussed previously, there are two mai types of stroke: ischemic ad hemorrhagic. The majority of this book describes Cambridge Uiversity Press

7 Cambridge Uiversity Press Acute Stroke Care: A Maual from the Uiversity of Texas-Housto Stroke Team Ke Uchio, Jeifer K. Pary ad James C. Grotta More iformatio What type of stroke? 7 the approach to either type of stroke, but there are specific chapters o ischemic stroke, TIA, ICH, ad SAH:. Ischemic stroke (Chapter 3).. Trasiet ischemic attack (Chapter 7).. Itracerebral hemorrhage (Chapter 8).. Subarachoid hemorrhage (Chapter 9). Cambridge Uiversity Press

8 Cambridge Uiversity Press Acute Stroke Care: A Maual from the Uiversity of Texas-Housto Stroke Team Ke Uchio, Jeifer K. Pary ad James C. Grotta More iformatio 2 What to do first The followig iitial measures apply to all stroke patiets. They are ecessary to stabilize ad assess the patiet, ad prepare for defiitive therapy. All curret ad, probably, future stroke therapies for both ischemic ad hemorrhagic stroke are best implemeted as fast as possible, so these thigs eed to be doe quickly. This is the geeral order to do thigs, but i reality, i order to speed the process, these measures are usually dealt with simultaeously. They are best addressed i the ED, where urget care pathways for stroke should be established ad part of the routie (see Chapter 10). Airway breathig circulatio (ABCs). O 2 via asal caula (routie oxyge delivery i ischemia might improve outcome).*. Itubatio may be ecessary if the patiet shows arterial oxyge desaturatio or caot protect their airway from aspiratig secretios. However, itubatio meas that the ability to moitor the eurological exam is lost. The best approach i such patiets is to prepare to itubate immediately, but before doig so, take a momet to be sure the patiet does ot spotaeously improve or stabilize with 8 Cambridge Uiversity Press

9 Cambridge Uiversity Press Acute Stroke Care: A Maual from the Uiversity of Texas-Housto Stroke Team Ke Uchio, Jeifer K. Pary ad James C. Grotta More iformatio What was the time of oset? 9 good ursig care (suctioig, head positio, etc.). Also, if eeded, use sedatig or paralyzig drugs with a short halflife, to allow for serial eurological exams.. Cosider puttig the head of the bed flat. This ca sigificatly help cerebral perfusio. The head of the bed may eed to be elevated if airway protectio ad cotiued ausea ad vomitig are cocers for those with obtudatio, ausea, severe dysphagia, or aspiratio risk.. Cosider ormal salie bolus cc if blood pressure is low.. If the blood pressure is high, atihypertesive treatmet is discussed i subsequet chapters (Chapters 3, 4, 5, ad 8). What was the time of oset?. Determiig the exact time of oset is critical for establishig eligibility for acute therapies, especially TPA (Chapter 4). It is very importat to be a detective. You will usually be told a time by the paramedics or ED triage urse, but be sure to recheck the iformatio you receive from them. If possible, try to speak persoally with first-had witesses, ursig home staff, etc. Ofte paramedic iformatio is based o a iexact estimate give to the paramedic whe they arrive o scee, ad the gets haded dow as fact. You ca ofte help establish the time of oset by fidig out the time that the emergecy call arrived at the dispatch ceter, ad work backwards with the perso who called. Other useful questios are to remid bystaders of their daily routie, TV shows, etc. that might help them accurately establish the time they foud the patiet or called the emergecy services.. I most cases, the oset is ot observed the patiet is foud with the deficit. I that case, or i patiets who awake Cambridge Uiversity Press

10 Cambridge Uiversity Press Acute Stroke Care: A Maual from the Uiversity of Texas-Housto Stroke Team Ke Uchio, Jeifer K. Pary ad James C. Grotta More iformatio 10 What to do first with symptoms, the oset time is the time the patiet was last see ormal. However, if the patiet awoke with symptoms, be sure to ask if the patiet was up i the middle of the ight for ay reaso (ofte to go to the bathroom) as sometimes this puts the patiet i the time widow for treatmet. How bad are the symptoms ow?. Examie the patiet ad do the NIH stroke scale (NIHSS) (Appedix 14).. The iitial stroke severity is the most importat predictor of outcome. Do a o-cotrast head CT. This will immediately rule out hemorrhage (Chapters 8, 9) as blood is bright o a CT. The iitial head CT should ot show obvious acute ischemic chages i patiets with ischemic ifarcts who are eligible for acute itervetios (Chapters 3 7), as acute ischemic chages become icreasigly apparet betwee 3 ad 24 hours.. The result will determie the first major brachig poit i therapeutic decisio-makig, to be covered i the subsequet chapters.. Obtaiig the CT is ofte the major impedimet i preparig for thrombolytic therapy, so efforts should be made to shorte door to CT time, which should be below 30 miutes. For istace, we allow the triage urse to order the CT sca if a stroke is suspected, ad stroke patiets will get preferece over ay other patiet for CT access. Aother problem is prompt readig of CT scas, especially i small hospitals i Cambridge Uiversity Press