Deans' stroke musings: Cerebral blood flow regulation systematically decreases after a stroke

Changing stroke rehab and research worldwide now.Time is Brain! trillions and trillions of neurons that DIE each day because there are NO effective hyperacute therapies besides tPA(only 12% effective). I have 523 posts on hyperacute therapy, enough for researchers to spend decades proving them out. These are my personal ideas and blog on stroke rehabilitation and stroke research. Do not attempt any of these without checking with your medical provider. Unless you join me in agitating, when you need these therapies they won't be there.

What this blog is for:

My blog is not to help survivors recover, it is to have the 10 million yearly stroke survivors light fires underneath their doctors, stroke hospitals and stroke researchers to get stroke solved. 100% recovery. The stroke medical world is completely failing at that goal, they don't even have it as a goal. Shortly after getting out of the hospital and getting NO information on the process or protocols of stroke rehabilitation and recovery I started searching on the internet and found that no other survivor received useful information. This is an attempt to cover all stroke rehabilitation information that should be readily available to survivors so they can talk with informed knowledge to their medical staff. It lays out what needs to be done to get stroke survivors closer to 100% recovery. It's quite disgusting that this information is not available from every stroke association and doctors group.

Friday, July 13, 2012

Cerebral blood flow regulation systematically decreases after a stroke

So have they thought that maybe pericytes haven't opened up yet?
http://oc1dean.blogspot.com/2011/09/restoring-capillary-blood-flow-after.html
You can easily verify if this hypothesis is correct or not by checking if these problems occur by ischemic vs. hemorrhagic stroke.
http://brainslab.wordpress.com/2012/07/13/38975849/
In everyday life, your muscles, metabolism, and nervous system work together to ensure that your cerebral blood flow meets the metabolic needs of your various brain regions. So if you are trying to scrutinize an impressionist painting, your body will likely relocate more blood flow to your visual cortex.
Following a stroke, this cerebral blood flow regulation is impaired. But, the degree and spread of the impairment is unknown. To investigate this, Hu et al. measured systemic blood pressure (BP) and used a transcranial doppler to measure cerebral blood flow velocity (BFV) at the same time.
In their model, better regulation of cerebral blood flow corresponds to a sharper phase shift between blood pressure (BP) and cerebral blood flow velocity (BFV). Individuals with the highest score of a 9 on their autoregulation index (ARI) have more regulation than those with the lowest score of 0, which corresponds to no phase shift.

When they compared patients who had experienced MCA infarcts (a common type of stroke) and healthy controls, they found that stroke patients had significantly less phase coupling between blood pressure and cerebral blood flow. This effect was pronounced over a wide range of blood pressure oscillation frequencies.

Given enough time and the right conditions, can the body repair its ability to regulate cerebral blood flow following a stroke? When the researchers examined this, they found no statistically significant difference between the BFV-BP phase difference and time since stroke.
But, that doesn’t mean that there’s a statistically significant lack of difference. So, further longitudinal studies will be needed to help clarify whether, in certain people in certain environments, the brain improves its cerebral regulation following stroke.

Reference
Hu K, Lo M-T, Peng C-K, Liu Y, Novak V (2012) A Nonlinear Dynamic Approach Reveals a Long-Term Stroke Effect on Cerebral Blood Flow Regulation at Multiple Time Scales. PLoS Comput Biol 8(7): e1002601. doi:10.1371/journal.pcbi.1002601