BANGI, 7 Septembar 2010 – UKM Medical Centre can now reverse a stroke attack and patients can get back to their normal life instead of spending years trying to recover from partial paralysis.
With the drug known as Recombinant Tissue Plasminogen Activator (r-tPA) stroke can now be reversed provided it is given within four and half hours of the stroke onset and under strict and controlled conditions.
This is to make sure that in trying to reverse the stroke physicians do not end up killing the patient, said Prof Dato’ Dr Raymond Azman Ali, the Senior Consultant Neurologist in Universiti Kebangsaan Malaysia Medical Centre (UKMMC).
Stroke starves the brain cells from oxygen which is vital for it to function. How this happen is the formation of blood clot in a blood vessel creating a blockage for the blood to flow to an area of the brain. After four and half hours of oxygen deprivation the affected brain cells will start to die.
During this crucial time an emergency back-up system kicks in the brain, opening dormant bridges between blocked blood vessel and healthy ones that normally supply blood to different areas of the brain. This enables blood to flow around the blockage, resupplying starved brain tissue with oxygen. This back up system known as collateral circulation forms by opening blood vessels which makes them vulnerable to bleeding.
The r-tPA which is only intended to dissolve the blood clot (or thrombus) within the affected blood vessel is highly likely to transform the stroke into a cerebral bleed (haemorrhage) and worsen the patient’s neurological deficit and even kill the patient
KRISIS and Stroke Reversal
Until recently the treatment for stroke is thought to be rehabilitation or prevention at best but not many know that there is such a thing as stroke reversal. “Yes, you can actually reverse a stroke and live a normal live again,” said Prof Raymond.
Stroke reversal is about keeping the cells that is being deprived of oxygen alive. The only way to do this is to resume the blood flow as soon as possible (reperfusion). This can be done by giving the patient the medication r-tPA which will dissolve the blood clot that is blocking the blood from flowing to an area of the brain.
Prof Raymond said UKM Medical Centre has come up with a stroke ready team called The Kuala Lumpur Regionalised Integrated Stroke Intervention System (KRISIS) to make sure help is given in time. It is currently the only programme of its kind in Malaysia. Prof Datuk Raymond is Chairman of KRISIS.
Many hospitals are reluctant to establish such an acute stroke intervention programme which involves a dedicated team comprising the full complement of specialised neurologists, emergency physicians, neurosurgeons, neuroradiologists, family physicians, nurses, medical assistants, rehabilation staff and pharmacists.
He said that such a programme also requires a CT perfusion scan and this is not available in many centres. A neuroradiologist is also needed to interpret the plain brain CT and CT perfusion scans in order to confidently predict the outcome from reperfusion procedures.
“A lot of hospitals are stroke ready but we are the only hospital with this programme. Many hospitals do not want to embark on such a comprehensive programme because they do not possess the full complement of human and physical resources. I know of a few private hospitals which are not fully prepared and some of their patients have succumbed to serious complications.
“Not only is it important to have expertise in brain scan interpretation, it is equally, if not more important that everyone in the team is an expert in stroke management.”
At the moment KRISIS conducts regular workshops to train doctors, nurses and assistant medical officers to be competent in stroke management. It is basically aimed at teaching them to recognise the early symptoms and signs of stroke and who to give and not to give the r-tPA.
KRISIS is a comprehensive management system from pre hospital to post hospital care, right from when you call 999; they alert the ambulance team who already know what to do in the ambulance. Once the patient gets to the emergency department, the KRISIS team will know exactly what to do and who else to channel the patient to.
One of the main reasons why stroke patients do not recover is when they take their own sweet time to get medical treatment. Once the symptom is apparent many of the patients prefer to seek alternative traditional treatment.
In reality if they come to hospital immediately and the blood flow to the brain can be restored the patient is highly likely to recover fully.
“If the patient comes to us within four and a half hours InsyaAllah we can reverse the stroke but if the patient comes after that, that is after the onset of his or her symptoms, that treatment that we give may kill,” he said.
How a stroke is reversed
The UKMMC stroke team is all on call 24 hours a day and seven days a week. The on call members of this elite team must have their pagers and phones on at all times.
Once a stroke patient arrives by ambulance at UKMMC, one of the first persons who will be at the scene is the radiologist who will assess the CT perfusion scan.
The CT perfusion scan is able to identify viable brain tissue within the area of the infarct, which cannot be detected by routine magnetic resonance imaging (MRI). Magnetic resonance angiography (MRA) is usually also performed to demonstrate the artery in the brain which is blocked. r-tPA is indicated when the area of the brain (identified by the CT perfusion scan) perfused by the blocked artery (identified by the MRA) is still viable (i.e. still perfused or receiving blood supply).
“The CT perfusion scan, often shows that the blood flow in the affected area of the brain is less than it should be, indicating that this area is in jeopardy of being an infarct,” said Prof Raymond.
Why would a patient suspected of suffering from a stroke still has to endure a CT scan while his life may be hanging on the balance?
The CT scan is conducted to determine whether the patient has a haemorrhagic stroke or an ischaemic stroke. If the patient has an ischaemic stroke, brain cells (neurons) die as a result of lack of blood supply, and this area of dead neurons is known as an infarct.
The brain CT scan is often normal in the first 24 to 48 hours of an ischaemic stroke, but is always abnormal right from the onset of a haemorrhagic stroke. Hence, a normal CT scan in a patient presenting with a stroke is synonymous to an infarct. Some patients, however, may show evidence of the infarct right from the beginning, particularly if the infarct in large. .A hemorrhagic stroke is caused by leakage of blood from a burst blood vessel into the surrounding brain tissue. Such patients are referred to the neurosurgeon to remove the blood clot, which often continues to enlarge and compress the adjacent brain tissue.
If a patient with this latter type of stroke is given r-tPA, it will lead to more bleeding and would eventually lead to fatality.
The UKM Medical Centre has staff trained in identifying who and when to give the r-tPA . This is to ensure timely delivery of the drug to reverse the stroke.
Most importantly they have also been trained to identify who should not be given r-tPA.
The Risk of Stroke reversal
Basically stroke reversal is through the medication r-tPA but the miracle of it in reversing a stroke is accompanied by the same degree of horrors.
Why do you need a team of experts before you administer the injection. The answer lies in who you should not give r-tPA.
“It is not that difficult to administer the medication; even the nurse can do it but the training is not so much in how to give the medication but more in who you are not supposed to give to”.
r-tPA must be administered within four and a half hours after stroke onset. The drug is a thrombolytic agent - it not only dissolves the clot blocking the artery, but also interferes
with the clotting of blood in all areas of the body, and hence, other parts of the body may bleed,
including the brain itself. Patients with larger infarcts, very high blood pressures and previous bleeding disorders are more likely to suffer from r-tPA-induced bleeding. Patients with these conditions and those with known allergy to the drug should not be given the r–tPA even if they come sooner than four and half hours.
The KRISIS team will also organise road shows in the near future to train doctors, nurses and the public that that there is such a thing as a brain attack, r-tPA and stroke reversal.
“We must educate the doctors first. Some doctors may think that the treatment for stroke is just rehab and prevention. They don’t realise that we can actually reverse the stroke proces,” said Prof Raymond.