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The Stroke Unit _ Stroke Investigations by liuhongmei

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									     The Stroke Unit
            &
  Stroke Investigations
            Diane Ames
Imperial College, St Mary‟s Campus
             April 2008

                                     1
                   Format
Stroke ….
• Current drivers and background for change
• Thrombolysis
• London stroke services in future
• Stroke investigations
• How we manage our patients




                                              2
              The drivers!
2005   National Audit Office report
2006   RCP Audit
2007   National Stroke Strategy
2007   Darzi reforms Health Care for London
2007   NICE approval thrombolysis
2008   NICE consultation TIA and Initial
       Management of Acute Stroke
2008   RCP 3rd Edition National Clinical
       Guidelines & new audit
2008   NWL Stroke Strategy Group              3
“Faster access to better stroke care”
              NAO report 2005
Concluded
• Treatment was a post-code lottery
• Stroke - very expensive and very common
• Key - rapid access to specialised services
• Delays lead to  deaths/disability
• Recognised the “abandonment” on discharge
• Recognised need for higher priority


                                               4
   “Emergency response is generally
               lacking”
•NAO 2005 recommendations
                                           tPA
                                           ICH
     Better coordination
      LAS / Stroke teams
                       More acute                    ESD
                       treatments &
Increased              early scans
Awareness                             Better Community
                                           supports
                                                           5
             RCP 2006 Audit
• Only 54% patients > 50% stay in SU
• Too few stroke beds
• Delays in transfers (into,through & out)
• Few direct admissions (12%)
• Delays in CT brain scans
 (42% only within 24 hours)
• Patients managed on a Stroke unit had better
  results for all the key indicators

                                                 6
         Key indicators RCP 2006
                      n=13,625

•   Screened for swallow disorder < 24 hours
•   Brain scan < 24 hours
•   Aspirin within 48hours
•   PT within 72 hours; OT within 7 days
•   Weighed, mood assessed
•   Anti-thrombotics ( AF)
•   Rehab goals documented
•   OT home visit (removed this round- 2008)

                                               7
        Delays: Stroke Onset to hospital
        (days)

                        National Sentinel Stroke Audit 2006




0.9% patients took > 10days to be admitted              8
      More significantly…..


Stroke Onset to hospital admission
(hours)
             RCP 2006 National Sentinel Audit




                                           9
The main driver for all
current developments

        December 2007




Treatment delays
can result in
    1.9 million
neurons lost /minute
                    10
      National Strategy for Stroke
                  2007
       10 point action plan focussing on:

•   Awareness                 •   Stroke Unit quality
•   Prevention                •   Rehabilitation
•   Carer involvement         •   Community Supports
•   Acting on warnings        •   Workforce issues
•   Stroke- a medical         •   Service networks
    emergency


                                                        11
Hyper-acute treatments




                         12
       Emergency stroke pathway

•   Suspect a stroke, ring 999
•   LAS use pre-assessment tool (FAST)
•   Pre-alert “hyperacute” receiving hospital
•   “24/7 thrombolysis service available”
•   Stroke team available
•   Immediate scan / decision to treat
•   Transfer to SU
•   Stroke networks emerging to channel patients to
    receiving centres
                                                  13
LAS Validated tool
•Use to triage to centre
•Public awareness
campaign




                           14
                     Ischaemic penumbra

   Penumbra
   Poorly perfused




Core of infarction
   DEAD tissue                Thrombus or embolism




Ischaemic /poorly perfused brain cells may be saved
       from infarction by prompt treatment       15
                   Thrombolysis
• rt PA i/v - on licence in Europe since 2002
• Patients meeting inclusion criteria are able to
  receive treatment < 3 hours of onset of event

• ( 6 hours IST-3 – on trial 9-5)

• 24/7 stroke service at Imperial ( SMH & CXH sites)
• Highly effective (only 10 people need to be treated
  to prevent 1 becoming dead or disabled)
• Risk of intracerebral / other haemorrhage
                                                    16
                                 Evidence
1. NINDS rt-PA study                  (NEJM 1995;333(24);1581-7)
• Showed improved outcomes but  risk of ICH
2. 2 major reviews
   a) Cochrane (18 trials, 5727 patients, 4 drugs: rtPA, SK, UK, rpUK)
   b) rt-PA pooled data          (NINDS, ECASS , ATLANTIS)

a) Cochrane 2003
• Significant  in death & dependency
    O.R. 0.8 (95% CI   0.69%-0.93%)

•    Non Significant excess of deaths O.R 1.13 (0.86-1.48)
•    „The data…may justify the use of thrombolytic therapy‟
                                                                   17
18
                 ICH in SITS-MOST register

• Obligatory register n= 6482 treated with rtPA
• 3/12 mortality 11.3% (cf 17.3 % in RCTs)
• „Symptomatic ICH‟ = 1.7%
  (type 2 bleed, ↓NIHSS ≥ 4)

• „Fatal ICH‟ @ 24 hr = 0.3%
  (type 2 bleed → death @ 24 hr)

• „Fatal ICH‟ @ 7 days = 2.2%
  (any bleed → death @ 7 days)
                 Wahlgren N et al Lancet 2007; 369: 275–282
                                                        19
             SITS-MOST register

• “Mortality rates in first 3 months were
  lower in SITS-MOST (11.3%) cf RCTs (17.3%)”
• “Functional independence at 3 months was
  higher in SITS-MOST (54.8%) cf RCTs(50.1%)”
• Concluded
“The results of SITS-MOST confirm that routine
 use of alteplase within 3 hours of ischaemic stroke
 has a safety profile at least as good as that seen in
RCTs”
                                                    20
                  NICE, June 2007


• „Alteplase is recommended for the treatment of
  acute ischaemic stroke‟
• „within 3 hours of the onset of stroke symptoms‟
• „Clinically and cost effective‟
• „Healthcare organisations should ensure they
  conform to NICE technology appraisals‟


                                                     21
     Urgent CT Brain Scan when…
•   If GCS is reduced
•   If thrombolysis considered
•   If on aspirin,other anti-platelet agent
•   If on warfarin
•   If history of falls, especially H.I. & alcohol
•   Fever, meningism, fluctuating conscious level
•   If uncertain and ?other pathology
•   Otherwise all scanned <24 hours

                                                     22
                 CT brain scan
• Will exclude haemorrhage
  - Acute infarcts are often NOT seen early
  - “normal” scan early does not exclude CI
• The diagnosis of stroke is clinical….
• Evidence exists for early anti-platelet Rx
• Occasionally will identify structural lesions




                                                  23
24
         St Mary’s Risk Factor profile
               n=1112 patients
AF                    20%
Diabetes              23%
Hypertensive          70%
Previous event        25%
Smoker                48%
IHD                   30%

         Vulnerable population!          25
     General stroke management-all

•   Full clinical assessment
•   Monitor coma scale,T, P, BP ,O2, BM
•   Rehydrate i/v (or po) after swallow screen
•   Catheter not routine
•   Thrombo-prophylaxis (TEDS)
•   Ideally direct admission
•   Feed early ( po or n/g)
•   Pressure relief

                                                 26
                    Medical
•  All assessed by Stroke SpR
•  Scan & Dopplers Day1
•  Secondary prevention early
•  Daily Consultant Neurologist or Stroke Physician
  review
• Further Investigations
   - to clarify deficit/diagnosis
   - to identify underlying aetiology
   - to manage the comorbidity
   - Unusual not to identify a cause
                                                  27
     Cerebral Infarction Investigations

• Atherothrombotic                50-60%
  RFs : DM,  BP,  lipids, PVD, smoker
• Cardioembolic                    20%
 AF, PAF, carotid disease,prosthetic valves,DCM, poor
 LV,aortic arch, PFO, atrial myxoma
• Non-atherothrombotic 10%
  Vasculitides,infective incl HIV, syphilitic, recreational drugs
• Haematological                   5-10%
 HbS, thrombophilias,Anti-Phospholipids,LAC, OC pill, HRT
                                                              28
                      Imaging
• Multi-modal CT
• CT perfusion/diffusion imaging
                - delineate the penumbra
• Multi-modal MRI
• MRI with DWI - diagnostic tool
• MRI           - posterior circulation lesions
• MRA           - looking at vessels , intra/extracranial
                - After intracerebral haemorrhage
                  ? Aneurysm,AVM, structural lesion
• Carotid Dopplers
                                                     29
                -if symptomatic stenosis – CTA/MRA arch
MRI




      30
CTA




      31
MRA extra or intra- cerebral
     and carotid dopplers




                               32
            Cardiovascular Ix

• ECG - AF important & common
       - Troponins when ECG changes
• Echocardiogram
         - especially when suspect cardioembolic
                  source
• Bubble echo – young/ unexplained
• Holter monitor
         - PAF, arrthymias common
         - PPM insertion not unusual
                                                   33
                   Bloods
• Routine FBC, Chemistry, Glucose,TFTs, CK
• Clotting
• Lipids, vasculitic screen,Treponemal serology
• Consider
- Troponins, ABGs
Young Strokes- search very hard
• Thrombophilia screen incl LAC, Anti phospholipids
  Homocysteine
• Consider
• LP, HIV
                                                34
                 Secondary prevention
                anti-platelets / anti-coagulate
•   Only after CT scan excludes haemorrhage
•   Add aspirin 300mg & Dipyridamole 25mg tds
•   Event on aspirin    - add dipyridamole
•   Event on A&D       - start clopidogrel
•   Aspirin intolerant - clopidogrel
    RCP 2004; Esprit; IST;


• Usually anti-coagulate for AF @ 2-4 weeks

                                                  35
    Longer term BP management
• Usually do not treat aggressively for~ 2 weeks
• Good control > important than agent used
• Beta -blockers – good for IHD, less beneficial in
  stroke
• Diabetic patients targets lower
• Usually use perindopril, indapamide, CCBs


                 60-70% patients are hypertensive

                                                      36
                   Lipids

• Simvastatin 40mg ( unless CK raised)
 - caution in renal failure, some drugs
• If known IHD & on atorvastatin
  - up-titrate to 40mg
• Concurrent ACS & Stroke - atorvastatin
• No stroke evidence yet for ezetimibe




                                           37
                     Diabetes
•   ~20% stroke patients diabetic nationally
•    Frequently identify new
•   Insulin by consensus if Blood Glucose > 15
•   If on metformin- stop few days
•   Problems with NG feeding/ PEG feeds
•   HbA1C; renal function; clearance; proteinuria
•   Careful BP management


                                                    38
         Intracerebral haemorrhage
                         on warfarin
•    risk of prolonged bleeding &  mortality
•   33% continue to bleed
•   Bleeding correlates well with GCS
•   Needs rigorous reversal of INR
•   Intensive monitoring
•   Use multiple agents /haematology advice
•   Rescan if GCS falls

      Steiner S et al .ICH Associated With Anticoagulant
      Therapy                        Stroke 2006;37:256-262
                                                              39
    London future stroke services
• NWT Stroke clinical reference group
• Developing standards, pathways
  In conjunction with
• Cardiac and Stroke Networks
• Hub(s) –offering a comprehensive service
• Spokes offering acute services ~ 7am-7pm
• How many comprehensive services???


                                             40
    Comprehensive Stroke Centres
                      US style
Outcomes
• Increased use of lytic agents – all routes
• Improved complex stroke management
• Specific interventions, surgery, ITU facilities, 24/7
  availability
• Improved outcomes & decreased LOS
  AHA recommends
• clusters of primary centres closely associated with
  comprehensive centres
                                                     41
                 Chain of survival!
• Detection -recognition of stroke
• Dispatch -call 999 & priority LAS
• Delivery -prompt transport & pre-hospital
             notification
• Door      - Immediate triage
• Data       - Assessment, bloods, imaging
• Decision - Diagnosis & decision re therapy
• Drug      - Appropriate drug/other intervention

 Adams et al. AHA Guidelines Stroke 2007;38;1655-1711

                                                        42
               Summary
• Stroke is a medical emergency
• 24/7 i/v thrombolysis routine
• Clot retrieval & intra-arterial Rx next
• Outcomes improved with rapid assessment
  and treatment on a stroke unit early
• Multi professional input is integral
• Stringent risk factor management is key

             Remember
        Time lost = Brain lost
                                            43

								
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