> [!references]-
> - [Stroke -- Rosens](x-devonthink-item://34BCE5FA-5D8A-4BBE-9655-35F24866FDB1)
> - [Dunn - thrombolytic therapy in stroke](x-devonthink-item://717870CB-CCEF-41AE-8E23-EFCC82ECB940)
> - [Dunn evidence for hrombolytic therapy in stroke](x-devonthink-item://02755D65-E1D2-45EC-B913-C2EE4B6A68BC)
> - [Rosen thrombolytic therapy for stroke](x-devonthink-item://34BCE5FA-5D8A-4BBE-9655-35F24866FDB1?page=10&start=1847&length=20&search=Thrombolytic%20Therapy)
> - [Core radiology - arterial territories](x-devonthink-item://C1EF00FD-576C-4C41-AE08-CA966611F572?page=683)
> - [Australia New Zealand stroke guidelines](https://informme.org.au/guidelines/living-clinical-guidelines-for-stroke-management)
> - [RMH Hyper-acute Stroke Management by the Stroke Team Protocol](x-devonthink-item://9FF55E37-4E4C-4CE2-9B00-F7353E58E17D)
see also: [[TPA]], [[endovascular clot retrieval]], [[Prévost's sign]], [[pupil exam#pupil deviation|pupil deviation]]
> [!example] Relevant trials
> - [[EXTEND]] - 2019 CT perfusion-guided thrombolysis up to 9 hours after onset of stroke
> - [TRACE-III](https://www.wikijournalclub.org/wiki/TRACE-III) - 2024
> - [thrombolysis trials](https://first10em.com/thrombolytics-for-stoke/)
>
# Modified rankin scale
| score | sx |
| ----- | --------------------------------------------------------------------------------------------------------------------------- |
| 0 | no symptoms |
| 1 | no significant disability despite sx; able to perform all usual activities |
| 2 | slight disability; unable to performa all pervious activities but able ot look after own affairs without assistance |
| 3 | moderate disability; requires some help, but *able to walk without assistance* |
| 4 | moderately-severe disability; unable to walk without assistance and unable to attend to own bodily needs without assistance |
| 5 | severe disability; bedridden, incontinent, requires constant nursing care and attention |
| 6 | death |
# NIH stroke scale
0 - no stroke
1-4 - minor stroke
5-15 moderate stroke
15-20 - mod/severe stroke
\>21 - severe stroke
thrombolysis contraindicated NIHSS >25
# CT perfusion study interpretation
see [bear CT perfusion study](bear://x-callback-url/open-note?id=2CD3AF23-7A23-49B5-ADD3-4C70C09444B5-56304-0000DB63CDC99868)
1. check for regional hypo-perfusion in vascular territory that supports clinical picture. **check time to peak** or **mean transit time**, if prolonged (aka reduced perfusion), hypo perfusion
2. compare CBF and CBV maps:
* areas with both reduced = *core*
* areas of normal or increased CBV within the area of reduced CBF = *penumbra* (note that TMax more accurate than CBV)
| measurement | core | penumbra |
| --------------------- | ------- | --------- |
| Time to peak & TMax | ↑ ↑ | ↑ |
| MTT | ↑ ↑ | ↑ |
| cerebral blood flow | ↓ ↓ | ↓ |
| cerebral blood volume | ↓ | - or ↑ |
| flow:vol ratio | matched | unmatched |
![[ABDF8F1C-427B-4D40-9D0B-2948CBD816F5.png]]
Central volume principle for making perfusion maps:
$ CBF = \frac{CBV}{MTT}$
When cerebral perfusion pressure (CPP = MAP - ICP) drops below threshold of auto regulation, compensatory vasodilation becomes overwhelmed, and CBF begins to decrease correlation with CPP reduction. as a result, RMM will be prolonged. Initially, this is enough to maintain O2 delivery to tissues, but it is unsustainable.
**Infarct Core** already infarcted brain tissue. significantly reduced CBV, significantly decreased CBF, prolonged MTT> decreased CBF relative to normal brain tissue often used to identify the ischemic core
**Infarct penumbra**- prolonged MTT, but only moderately decreased CBF and normal or increased CBV (due to auto regulatory vasodilation). penumbra is derived from subtracting the ischemic core from the perfusion deficit
# Stroke Recrudescence
see [JAMA 2017 Recrudenscence of deficits after stroke](https://jamanetwork.com/journals/jamaneurology/fullarticle/2646625)
Transient worsening of poststroke neurologic deficits or reemergence of previous stroke-related deficits (or poststroke recrudescence) in the setting of toxic metabolic factors.
# stroke territories
## posterior circulation
see [Alteplase for Posterior Circulation Ischemic Stroke at 4.5 to 24 Hours.](bookends://sonnysoftware.com/ref/DL/260626)
- **Posterior cerebral artery (PCA)** stroke causes ipsilateral [[Cranial nerve palsies|CN III palsy]] and contralateral [[Visual fields|homonymous hemianopia]] (visual field change), sensory loss without motor
- **Vertebrobasilar strokes** result in ipsilateral cranial nerve (CN) deficits and contralateral hemiparesis.
- **Wallenberg syndrome** (lateral medullary syndrome aka ischaemia in the posterior inferior cerebellar artery territory) causes [[vertigo]], [[pupil exam#Horner Syndrome|Horner Syndrome]], ipsilateral facial numbness, loss of corneal reflex, along with contralateral loss of pain and temperature.
---
# ACEM position on thrombolysis of stroke
- ==No mortality benefit==
- IV thrombolysis administered to selective patients within 3 hours of symptom onset may increase the odds of a better outcome
- **NNT** to achieve functional independence mRankin 0-1 is 10, 13 for good outcome; 7 within 3 hours 18 at 3-4.5 hours
- Treatment has risk of sICH **NNTH** (number needed to harm) being 42, 122 for risk of death
- Disagreement about strength of evidence
NINDs
- OR favourable outcome better in <90mins
ECASS 1-3
- imbalance of stroke severity favouring tPA groups
- industry sponsored
- favourable mRankin score at 90 days --> carried to 1 year
EPITHET
IST3 - @18months 4% benefit alive + independent NNT 25
Cochrane review 2014 - given up to 6 hours reduces proportion of dead or dependent people, <3 hours more benefit; benefit despite increase in sICH
Effects on ED:
- small number of patients eligible
- disruption of care for other patients who may benefit more from treatment (5-10 code strokes for every patient who is thrombolysed)
- preferential allocation of resources who may equal/higher risk of death/disability
- ongoing patient management reduces care to other ED patients
- stroke mimics 5% --> exposes risk without benefit
# Stroke trials and evidence
## thrombolysis
- [Alteplase for Posterior Circulation Ischemic Stroke at 4.5 to 24 Hours.](bookends://sonnysoftware.com/ref/DL/260626)
- [Should thrombolytics be given >4.5 hours after stroke onset?](cubox://card?id=7298980291551431258)
# Related Questions
## stroke
- [ ] 1Q: [Stroke](x-devonthink-item://EE8AC47E-BE40-4377-885E-FA9C91C8C262?page=1) -- [Answer]()
- [ ] 2Q: [Collapse, GCS 10](x-devonthink-item://F0498813-9350-484C-AD5B-6FF7C3AE9015?page=10) -- [Answer](x-devonthink-item://A491A3F6-FD6D-492F-BCBE-7F7BAE101EDF?page=7)
- [ ] 3Q: [Stroke](x-devonthink-item://7FCD3940-4BB4-45FE-86A6-E5707E82D5B5?page=44) -- [Answer](x-devonthink-item://3263A68A-96A6-43EC-985B-43260C3509BF?page=16)
- [ ] 4Q: [Haemorrhagic Stroke](x-devonthink-item://B74AA648-7583-42CC-9AC9-1FDBD09A2750?page=2) -- [Answer](x-devonthink-item://2088AEED-9FCF-4CF0-B58D-E4279D4BCC76?page=2) -- [prop](x-devonthink-item://5F365535-E019-4C8D-8402-2E764B328988?page=1)
- [x] 5Q: [Stroke](x-devonthink-item://92A26505-5B6B-4ADD-995F-6AAA2E05C637?page=16) -- [Answer](x-devonthink-item://0808A030-AF19-4671-BE84-3E8BCBEC6124?page=17)
- [ ] 6Q: [Elderly Man with Difficulty Walking](x-devonthink-item://7061D1B4-0AB9-4963-B3B0-23BDD975B2CD?page=30) -- [Answer](x-devonthink-item://3F30C77E-E23E-4200-89FE-48A41618E0C2?page=21)
## tia
- [ ] 42Q: [TIA and Stroke](x-devonthink-item://73409C77-B2FA-4E0A-AEB3-5EB284457F0C?page=52) -- [Answer](x-devonthink-item://5A848952-80E3-4184-B553-368412A69917?page=34) -- [prop](x-devonthink-item://2A1F4A99-92AE-4C8E-B325-AE448BD46AC6?page=12)