What happens during a stroke? - Vaibhav Goswami

譯者: Chen Chi-An 審譯者: Marssi Draw

Every two seconds, someone somewhere in the world experiences a stroke.

每兩秒鐘世界上某處 就有一人中風。

And one out of every six people will have one at some point in their lives.

每六人就有一個在生命中的 某個時刻經歷過中風。

Strokes deprive brain cells of oxygen

中風剝奪了腦細胞的氧氣，

and are one of the most common causes of death

並且是常見的死亡原因，

and a leading cause of preventable disability.

也是造成可預防殘疾的主要原因。

When someone experiences a stroke, quick medical care is critical,

當有人中風時， 快速的醫療照顧至關重要，

and can often help avoid permanent brain damage.

且有助於避免永久性的腦損傷。

But what causes strokes in the first place?

但究竟是什麼原因引起中風？

And what can doctors do to treat them?

醫生可以怎樣治療呢？

The brain makes up just 2% of your body’s mass

大腦最多只佔 2% 的重量，

but consumes more than 20% of the oxygen in your blood.

但消耗超過 20% 血中氧氣。

That oxygen is carried to the brain through a system of arteries.

氧氣藉由動脈系統送到大腦，

Carotid arteries supply the front of the brain,

頸動脈供應大腦的前側，

and vertebral arteries supply the back.

脊椎動脈供應背側；

These are connected to each other,

他們相互連接，

and divide into smaller and smaller vessels

並分枝成越來越小的血管，

that get billions of neurons the oxygen they need.

讓數十億的神經元 得到他們所需要的氧氣。

If the blood flow is interrupted, oxygen delivery stops and brain cells die.

如果血流中斷，氧氣輸送將停止， 而腦細胞將死亡。

There are two ways this can happen.

造成中風的原因有兩個：

Hemorrhagic strokes are when a perforated vessel allows blood to leak out.

出血性中風指血液 從破損的血管中滲出，

But the more common type is the ischemic stroke,

但缺血性中風更常見，

when a clot blocks a vessel and brings blood flow to a halt.

此指當一個血塊阻塞血管 而使得血液停止流動。

Where do these clots come from?

這些血塊從哪裡來？

On rare occasions, a sudden change in heart rhythm

在極少數情況下，心律突然改變，

prevents the upper chambers of the heart from contracting normally.

阻止心房正常收縮，

This slows down blood flow,

這減慢了血流量，

allowing platelets, clotting factors, and fibrin to stick together.

讓血小板、凝血因子 和纖維蛋白黏在一起。

The clot can be carried up

凝塊可以被運送，

towards the arteries and blood vessels supplying the brain

朝向供應大腦的動脈和血管，

until it gets to one it can’t squeeze through.

直到抵達一條過不去的血管，

This is called an embolism

這被稱為栓塞。

and it cuts off the oxygen supply to all the cells downstream.

栓塞造成下游細胞缺乏氧氣供應。

The brain doesn't have pain receptors, so you can't feel the blockage itself.

大腦沒有疼痛感受器， 所以你不能感覺到堵塞，

But oxygen deprivation slows brain function

但是缺氧降低大腦的功能，

and can have sudden, noticeable effects.

並可能有突然且明顯的影響。

For example, if the affected area is responsible for speech,

例如負責講話的區域受影響，

an individual’s words may be slurred.

病患講話就可能口齒不清；

If the stroke affects a part of the brain that controls muscle movement,

如果影響大腦控制肌肉的區域，

it can cause weakness, often just on one side of the body.

就可能會導致肌肉無力， 且往往只在身體的一側。

When this happens, the body will immediately try to compensate

當這種情況發生時， 身體會馬上嘗試代償，

by diverting blood flow to the affected area,

將血液分流至受影響區域。

but this isn’t a perfect solution.

但這不是一個完美的解決方案，

Eventually, the oxygen-deprived cells will start to die,

最終，缺氧的細胞將開始死亡，

leading to brain damage that may be severe or permanent.

可能導致嚴重或是永久的腦損傷。

That’s why it’s important to get medical care as fast as possible.

這就是為何盡快得到 醫療照顧非常重要。

The first line of treatment is an intravenous medication

第一線治療是一種靜脈注射藥物，

called Tissue Plasminogen Activator,

稱為組織纖維蛋白溶酶原活化劑，

which can break up the blood clot

這可以分解血塊，

and allow blood to flow again in the compromised artery.

讓血液在受阻動脈中再次流動。

If it’s delivered within a few hours,

如果在幾個小時內施藥，

this medication greatly increases the chance of surviving the stroke

將大大提高存活率。

and avoiding permanent consequences.

並避免永久性的後果。

If Tissue Plasminogen Activator cannot be given

如果不能採用此活化劑，

because the patient is on certain medications,

因為病人正在服用某些藥物、

has history of major bleeding,

有大出血病史，

or the clot is particularly large,

或者血塊特別大，

doctors can perform a procedure called an endovascular thrombectomy.

醫生會執行一個手術， 稱為血管內血栓切除術。

Using a fluorescent dye that illuminates the blood vessels under a strong x-ray,

醫生使用螢光染料 使血管在高能 X 光下顯影，

the physician inserts a long, thin, flexible tube called a catheter

並從腿部動脈置入 一條細長軟管，稱為導管，

into an artery in the leg

and maneuvers it all the way to the blockage.

一路延伸直到堵塞處，

A retriever is passed through this catheter.

取出器經由導管進入。

It expands and anchors into the clot when it’s just past it.

當取出器穿過血塊時， 它擴張並固定住血塊，

The catheter then pulls the clot out when it’s removed.

接著在取出導管時將血塊移除。

These treatments need to be delivered as soon as possible

這些治療越快越好，

to preserve brain function,

才能保存大腦功能，

which means figuring out fast if someone is having a stroke.

這意味要迅速分辨是否中風。

So how can you tell?

那麼你怎麼知道？

Here are three quick things to try:

這裡有三個快速的試驗：

1. Ask the person to smile.

第一，請他微笑。

A crooked mouth or facial drooping can indicate muscle weakness.

歪嘴或臉部下垂 可能暗示肌肉無力。

2. Ask them to raise their arms.

第二，請他們舉手。

If one drifts downward, that arm weakness is also a sign of a stroke.

如果一隻手下滑， 該手臂無力可能是中風徵狀。

3. Ask them to repeat a simple word or phrase.

第三，要求他們複述簡單的字詞。

If their speech sounds slurred or strange,

如果他們的聲音聽起來 模糊還是怪異，

it could mean that the language area of their brain is oxygen-deprived.

可能表示語言領域的大腦缺氧。

This is sometimes called the FAST test, and the T stands for time.

這有時被稱為 FAST 測試， T 代表時間。

If you see any of those signs, call emergency services right away.

如果你看到任何這些跡象， 立即致電緊急服務，

Lives may depend on it.

生死可能取決於它。