A game-changing surgical technique is significantly improving stroke victims’ chances of recovery.
A game-changing surgical technique is significantly improving stroke victims’ chances of recovery.
About 24 New Zealanders a day have a stroke, and until recently, all doctors could do for many of them was watch and wait. When the blood flow to the brain is interrupted – very often blocked by a clot – the brain cells are starved of nutrients and quickly damaged. Those who survive an ischaemic stroke receive speech therapy and physiotherapy to rehabilitate them as much as possible, but for many, the consequences are devastating, and strokes remain a leading cause of disability.
A game changer for an increasing number of patients has been a surgical technique that allows doctors to remove the clot from the artery before the brain is extensively damaged. Speed is important here, so it is crucial to recognise the signs of stroke in the first place – these include sudden difficulty speaking, weakness on one side of the body, drooping on one side of the face, sudden blurred or lost vision – and call an ambulance.
At hospital, a number of scans need to happen, including the less commonly performed perfusion scan, which looks at blood flow in each region of the brain. If judged a good candidate, the patient is then whisked into surgery, where the clot is removed and the blood starts flowing normally again.
Auckland City Hospital can now offer this procedure around the clock. Interventional neuroradiologist Stefan Brew says it has made a difference for a number of patients who have avoided a catastrophic stroke and been left with far less serious effects on their speech and movement.
“Left untreated, people stand roughly a 30% chance of getting home and living independently,” he says. “With the ones we’re treating, we’re getting about 80% home. That’s a dramatically effective intervention. Some will go from being paralysed down one side of their body and not speaking properly to seeming absolutely normal in the space of an hour or so.”
Initially, it was believed there were only five or six hours before brain damage would be too great for the
treatment to be worthwhile. But now that time has been extended for some patients whose brains effectively reroute, opening up tiny vessels to allow a small amount of blood to get through to the area of the brain starved of blood by the clot.
“We’re all plumbed differently, so how effective the process is varies radically from person to person,” says Brew. “But it can give you a bit longer – potentially up to 24 hours – within which some parts of the brain will still be viable.”
Patients in whom this can make a big difference are those who have a stroke while sleeping. “A stroke is not painful, so it doesn’t wake people,” says Brew. “If they’re asleep, there’s a pretty high chance they won’t discover it until morning.”
With the limit set at six hours, these wake-up strokes were excluded from treatment because there was no way of knowing when in the night the stroke had happened. Now it is clear some people will benefit.
An extended time limit doesn’t reduce the urgency, because the faster a clot is removed, the more of the brain is likely to be saved. “Only carefully selected patients will benefit up to 24 hours, and even those would almost certainly have done better if they’d been treated sooner.”
It is still early days for the procedure and there aren’t many surgeons with the skills to work inside the delicate arteries of the head.
“My colleagues and I are taking a bit of a beating in terms of the on-call arrangements,” says
Brew. “But none of us resent it because there is the opportunity to so radically alter a patient’s outcome.”
Last year, Auckland City Hospital treated 100 patients. Brew hopes that figure will reach 500-600 a year and that hospitals in the other main centres will continue to improve the service they provide.
“In a way, we’re in the position cardiologists reached 30 or so years ago with patients who’d had a heart attack due to a blocked artery. They very rapidly set up 24/7 services to get those arteries open. We’re 30 years behind.”
“Some go from being paralysed down one side and not speaking properly to seeming normal in an hour.”