It is good news; until 2018, we knew that neurosurgeons can salvage living neurons only if they remove the clot within six hours of the block. Now, we know it is not so. They can go ahead with the operation if a patient is ready for the surgery even after six hours.
About the study
This finding was published in the The New England of Journal of Medicine in 2018. An eminent group of US researchers conducted this study recruiting stroke patients from 32 stroke centres; so, it was a multi-centre study. They compared recovery levels of two groups of stroke patients after three months; one group received only the clot-buster drug and the other group underwent the clot-removal operation. They prematurely terminated the study after evaluating the results of 182 patients – the result was so obvious – after three months, 45 per cent of people became functionally independent as against 17 per cent of those who received only the clot-buster drug.
This study was about ischaemic stroke. In an ischaemic stroke, brain cells die as a result of a block to blood flow by a blood clot. More than two-thirds of strokes occurs due to a blood clot. There are other types of stroke too. Read about stroke types through this link.
Clot removal surgery (Thrombectomy)
The following caption was published in the NIH Director’s blog. As we all can see, a tiny tube is sent to the blocked area to retrieve the clot.
This is not a reason to delay in seeking medical attention!
However, this does not mean that anyone suspected of having a stroke can afford to delay seeking hospital care; we should ideally receive specialised care within the first hour of a suspected stroke – even earlier the better. One with a confirmed diagnosis should receive the clot-buster drug within the first hour from the “last known normal”. you can read about it more through this link.
Imagine the following trail of events: you start to observe one or more F.A.S.T. stroke symptoms and signs in a person; you call an ambulance; emergency responders arrive at the scene; they determine of a stroke; they rush the person to a stroke unit; the person is treated with a blot clot-dissolving medication. If all these events occur within the first hour from the time of detection, that is the golden hour.
This is because of every passing second matter. Ans this is why we call, “Time is Brain”. Read about it more on the “Journeys to the Brain” series.
Time is the critical factor; 32,000 neurons die ever passing second as Jeffrey L. Savers wrote in 2005.
Why this hour is golden?
A group of Scandinavian researchers (Advani et al. 2017) have shown that irrespective of age and pre-existing disease conditions, those who were treated within this golden hour reached excellent outcomes. This is a very significant finding because age (how much old an individual is) should not be considered as a factor to call for an ambulance and to intervene at the hospital.
Not only they, but other researchers have also demonstrated the importance of this hour.
However, passing this golden hour does not mean that we should lose our hope of salvaging the affected brain tissues. The Canadian best practice guidelines advocate the onset-to-needle time as “four and a half hours” (page 3) from the onset of symptoms.
FAST campaign from the University College London hospitals (Courtesy: University College London Hospitals website.
The above public health message summarizes the signs and symptoms of a suspected stroke event.
In this creative message, each letter represents a word:
- F : face,
- A :arms,
- S : speech,
- T : time.
Knowing what these letters represent is not enough. We need to ask its associated specific questions.
How to suspect a stroke
- Look at the face
Ask: can you smile?
Observe: whether one side of the mouth or an eye is drooping
- Compare both arms
Ask: Raise your both arms
Observe: Whether the person is having any difficulty of raising one or both arms
- Observe the speech
Observe: whether the person cannot speak or understand as before
- Check the time
Call an ambulance of you observe any one of the above
Other similar public health messages
The following are several popular messages adopting the same acronym technique. Among many, I chose the above one because its visuals explains everything that we should know succinctly.
Heart and Stroke Foundation of Canada message
University College of London (England) Hospitals message
American Heart Association message