vascular lesions of the CNS Flashcards
what is the most common vascular injury to the CNS?
strokes - ischemic or haemorrhagic
what are vascular lesions that can lead to haemorrhagic strokes?
-aneurysms
-arterial venous malformations
where are examples of aneurysms in the brain?
-circle of willis eg anterior communicating arteries
what is an aneurysm?
an abnormal bulge or ballooning in the wall of a blood vessel due to weakness in the vessel wall. If it grows too large, it can rupture, leading to life-threatening internal bleeding.
describe the epidemiology of aneurysms
-85% of subarachnoid haemorrhages are caused by aneurysms
-incidence of aneurysms = 1% of the population
what is the peak age for aneurysms?
-peak age is 40-60 years
what are risk factors for aneurysms?
-genetics - 20-25% of people with a SAH have a family history of it
-kidney disease
-HTN
-smoking
-alcohol
how are aneurysms treated?
-surgical clipping via craniotomy
-endovascular coiling via interventional radiology (metal coil passed up through circulation)
what are physio implications pre +post treatment for aneurysm ?
-pre treatment - patient is normally on bed rest 15 degrees head up
-post treatment- await clearance from neurosurgeon or neuroradiologist to mobilise
describe subarachnoid haemorrhage stroke
-accounts for 3% of all strokes, but 5% of all stroke deaths
-85% of SAH are caused by a rupture of an aneurysm
-10-15 per 100,000 people
what are the symptoms of a SAH?
-severe unrelenting headache - worse headache imaginable
-vomiting
-neck stiffness
-seizure
-reduced GCS
-limb weakness at time of onset
what are the investigations for a SAH?
-CT scan - confirms diagnosis in 95% of SAG if within 48 hours of bleed
-lumbar puncture - if CT scan negative
-MR angiography - detects aneurysms
what are complications of SAH?
-high risk of cerebral ischemia or infarction especially 4-12 days after onset
-patients can present as being cognitively “vague”
-vasospasm - have had this rebound constriction of the blood vessels after the haemorrhage
what is the treatment for vasospasm?
-hypertension
-hypervolemia
-haemodilution
in addition to vasospasm, what other conditions can people who have had a SAH present with?
-hypovolemia - fluid loss
-hyponatremia - kidney excessively secretes Na+
what are the physiotherapy implications for SAH?
-when can we mobilise??
-mobilising early can cause vasospasm but on the other hand, immobility is also detrimental eg clots etc
-needs to be evidence based practice = evidence + patient assessment - shared decision
what do we do if the SAH patient has had treatment, and we as physios dont know whether to mobilise them or not?
-liase with the team -outline the case for mobilising
-check vitals - especially HR and BR, ICP
-don’t proceed with MAP< 80 or >110)
-keep talking to the patient - if they start to seem vague - vasospasm? alert team
-do short frequent bouts of activity eg bedside activity first, STS etc
-NB drains eg external ventricular drains - need to be clamped before moving patient
what is an external ventricular drain?
a device used to drain excess CSF from the brains ventricles to release increased ICP
describe physiotherapy after SAH treatment
-similar approach to stroke - UMN problem
-presentation can be anything from dense hemiplegia to very mild balance impairment
-RAMP principles - restoration, adaption, maintain range and prevent inactivity + loss of ROM
-high incidence of cognitive impairment - could be mild to severe - write info down, communication with nursing team and family, show pictures
-balance rehab
describe arteriovenous malformations
abnormal tangle of blood vessels where arteries and veins are directly connected, bypassing normal capillary networks.
-a developmental abnormalities
-can burst and bleed similar to aneurysms, also dimities blood flow to surrounding areas
-most likely to bleed in younger patients 20-40 years
describe the clinical presentation of AVM
haemorrhage - present as
-epilepsy
-neurological deficit - large AVMs, close to basal ganglia
-headache
-cranial pulsation
how are AVMs managed?
-surgical excision
-stereotactic radio surgery
-embolisation of cerebral angiography
-occlusion of feeding vessels
describe physiotherapy management for AVMS
-not everyone with this will need to see physio, but people with a neurological deficit and or reduced mobility post intervention need to see physio
-presentation often similar to stroke
-note that people with AVM may have restrictions in first 5-7 days post surgery/presentation due to vasospasm
-talk to neurosurgical team
-once cleared o mobilise, proceed as normal, but be mindful of neurological changes
how are SAH or AVM assessed in terms of physio?
-NB database
-need to know how the patient presented, bleed or found an imaging
-deficits on presentation eg LOS, hemiplegia or weakness?
-if they had surgery - what was it, instructions for mobilisation, if they are pre-op, what’s the plan?
-speak to nurses and neurological team
-bedside assessments - check vitals, nursing obs, GCS, patients position + orientation of limbs, any drains or lines
when doing a subjective assessment of a SAH or AVM patient, what do we do?
-orientation + awareness - eg where are you etc
