Stroke, Head Trauma and conciousness Amy Wood, Haddy Cosh, Vishal Chauhan, Asfand Baig, Stewart O’Conner

Definition

 a syndrome of rapid onset of cerebral deficit (usually focal)  Lasting > 24 hours or leading to death and no cause apparent other than a vascular one

Stroke Risk Factors  Non Modifiable   Modifiable 

Stroke Risk Factors  Non Modifiable  Age  Male  FHx  Race – black/ hispanic  Modifiable  HT  IHD  AF  DM  Hypercholesterolaemi a  Smoking  Alcohol

Types    

 Ischaemia/ embolism causing cerebral infarct – 80%  Intracebral Haemorrhagic – 15%

Causes -Haemorrhagic      

 Ruptured aneurysm  Trauma (subarachnoid/intracerebral)  Dissection (carotid/vertebral)

Causes - Ischaemic      

 Cerebral Thrombosis  Cerebral Emboli  Give examples  Lacunar

Symptoms - General

 Weakness/Paralysis or numbness on contralateral side  Vertigo/dizziness  Headache  Visual loss/blurred vision  Faintness  Confusion  Speech problems  Difficulty swallowing  Cognitive problems  Memory problems  Consciousness alterations  BUT…DEPENDS ON SITE

Stroke Syndromes        

 TACS - Total Anterior Circulation Syndrome  PACS - Partial Anterior Circulation Syndrome  LACS - Lacunar Syndrome  POCS - Posterior Circulation Syndrome

 What are the differences between them?

SyndromeSymptomsArtery TACS Higher Dysfunctions Dysphasias Visuospatial problems Homonymous Hemianopia Motor/Sensory Deficits ICA, MCA, (ACA) PACS 2/3 Similar to TACI Partial motor/sensory deficits Higher dysfunction alone MCA, (ACA) LACS Pure Motor or Sensory or Sensorimotor loss Ataxic Hemiparesis Small vessels (Perforating arteries) POCS Cranial nerve palsy & contralateral motor/sensory deficit Bilateral motor or sensory deficit Cerebellar signs Eye Movement deficits/isolated homonymous hemianopia Vertebral PCA

Extras - watersheds SyndromeSymptomsArtery Watershed ACA- MCA "Man-in-a-Barrel" Syndrome Aphasia Internal Carotid Artery occlusion Watershed MCA- PCA Visual ProcessingICA Susceptibility to ischaemia: Systemic BP drop ACA-MCA occlusion of carotid

TIA

 Sudden focal deficit – usually only a few seconds  Presentation very similar to stroke  Amaurosis fugax??  <24 hours with complete recovery  Issue: after 1 hour ischaemic damage has already occurred  High risk of recurrence and full stroke

Causes- TIA

Carotid artery insufficiency – 80% Veterbrobasilar Insufficiency – 20% Circle of Willis – collateral supplies

Management 1. Assessment/ diagnosis  Location  Subtype  Cause 2. Acute intervention 3. Secondary prevention  Reduce risk factors

Assessment and Diagnosis

Assessment: Diagnosis  Clinically usually  FAST  Imaging - <3hrs  CT  Available  Exclude haemorrhage  MRI  If brainstem or cerebellar symptoms

Urgent CT required

Acute intervention

 Admit to Acute Stroke Unit for assessment  Iscahaemic – Thrombolysis rTPA within 3 hrs of symptoms  Haemorragic – emergency surgery

 Antiplatelet drugs (Aspirin mg) if infarct  Contraindicated if haemorrhage!!  Monitor/prevent complications  Physiological monitoring for first 72 hours to maintain CO and supply to brain  HR, Temperature, BP, O2 sats, Blood sugar, ECG Acute intervention

Complications

 Post-stroke pain/thalamic pain  1 week- 6 months after stroke  Anywhere in spinothalamic system  Contralateral side referral of pain  Burning + sharp  Hyperalgesia & Allodynia  Treat as for neuropathic pain  TCAs

Layers of the brain a) Pia mater b) Arachnoid mater c) Dura mater d) Superior sagittal venous sinus e) Skull f) Falx celebri g) Subarachnoid space

 Pia  Arachnoid  Dura Subarachnoid – arteries Subdural – Bridging veins Epidural – Meningeal arteries

Normal CT  Usually going to be symmetrical  Ventricles symmetrical and equally full

Midline Shift  Coup injury – injury on same side of force  Contra coup– injury on the opposite side on injury  If you see midline shift, you have a high pressure situation

Case 1  Young lady hit on the side of head by a glass at a gig, seemed to recover, Found slumped 50 minutes later  Ix?  CT/MRI, x-ray if fracture  Where may she have been hit?  Pterion  What bones converge here?  frontal, parietal, sphenoid, temporal  What does this area cover?  Middle meningeal artery  Type of intracranial haemorrhage?  extradural (epi)  Type of blood characterises this?  Arterial  Why passed out?  raised ICP  Rx  surgical

Extradural haematoma:  Midline shift  Lenticular shape  This can be middle meningeal artery – pterion bone breaks  Cerebral perfusion pressure = mean arterial pressure – ICP  Extradural haematoma you give Mannitol – 100mL at 20%  Diuretic

Case 2  Old alcoholic man had a fall in the park now noticed to be very drowsy with low consciousness  Ix:  CT/MRI  Likely haematoma?  Subdural  Other symptoms?  Headache, confusion, N/V, tinnitus, speech and visual problems, dizziness, weakness  Where is the bleed likely to be?  bridging veins  Type of blood?  venous  Rx depends on size + growth rate: often conservative (body reabsorbs), sometimes burr-hole drainage  Acute or Chronic

Subdural Haematoma:  Runs along the surface of the brain, underneath the dura  Depending on the GCS score of the patient you may need to remove it  Midline shift

Subarachnoid Haemorrhage  Sudden onset severe headache, often at the back of the head, Neck stiffness, Impaired consciousness (drowsiness / coma), Cranial nerve signs, Hemiplegia  The bleeding occurs as the result of rupture of aneurysm (80%) and AV malformations (15%) or trauma

Contusion (bruise)  Intra- axial  As bruise swells, pressure goes up – all features of raised ICP (coma)  If you remove them you need to do a craniotomy

Diffuse Axonal Injury RTAs / shaken baby syndrome  If a rotational force is applied, the axons are damaged and you can have damage very far away from the original injury – diffuse axonal injury  Small contusions all over the brain  The worse it looks on the CT scan, the worse the injury in the patient – especially if you see an injury in the brainstem  DAI doesn’t look as bad on CT as some of the other ones, but can be much worse

Le fort Fractures

Blow-Out Fractures

With a mass lesion why do you not get an immediate loss of consciousness?

 Due to an ability to Compensate!  Intra cranial vol = vol CSF + vol Brain + vol blood + vol Mass lesion  Skull can’t expand  Compensation – ml CSF in to lumbar cisterns  Compensation exceeded  Increase in ICP  herniation

What are the 3 key symptoms of raised ICP?  Papilloedema  Headache  Nausea and Vomiting

Label diagram

Name two areas of the brain that can be damaged, leading to loss of consciousness?  Compression of reticular formation from herniation  Large damage to cortical regions

How unconscious are they?  What is the main tool that we use to measure this?

Glasgow Coma scale

“Patient has Glasgow coma score of 9” What’s wrong with this?

It’s more useful to say:  GCS = V1 E3 M5 V3 E3 M3 etc.  They are different situations that may need managing differently

Three indicators of change of brain function in the unconscious patient?  Reaction to painful stimulus – (part of Glasgow Coma scale)  Vestibulo-ocular reflex  E.g Caloric test, doll’s head test  Size and reaction of pupils

What are the three components of consciousness?  Alertness - upper brainstem reticular formation - wakefulness  Awareness - cerebral cortex state of awareness and interaction with environment  Attention - limbic system and frontoparietal association areas - affect, mood, attention, motivation pay attention to