How do blood transfusions work? - Bill Schutt

Translator: 潘 可儿 Reviewer: H.L. Au

In 1881, doctor William Halsted rushed to help his sister Minnie,

1881 年，William Halsted 醫生 衝去救佢嘅妹妹美妮

who was hemorrhaging after childbirth.

因為美妮產後大出血

He quickly inserted a needle into his arm,

佢迅速將針插入自己嘅手臂

withdrew his own blood, and transferred it to her.

抽自己嘅血，再輸血救妹妹

After a few uncertain minutes, she began to recover.

唔知幾分鐘之後 美妮開始恢復

Halsted didn’t know how lucky they’d gotten.

海斯德唔知道佢哋有幾好彩

His transfusion only worked because he and his sister

佢之所以輸血成功，只係因為

佢哋兩兄妹嘅血型咁啱一樣——

happened to have the same blood type—

something that isn’t guaranteed, even among close relatives.

血型唔一定吻合 就算係近親都好

Blood types hadn’t been discovered by Halsted’s time,

喺 William 嘅時代 大家仲係對血型一無所知

though people had been experimenting with transfusions for centuries—

雖然幾個世紀以來 一直有人嘗試輸血

mostly unsuccessfully.

但大部分都失敗咗

In 1667, a French physician named Jean-Baptiste Denis

1667 年，一個叫 Jean-Baptiste Denis 嘅法國物理學家

became the first to try the technique on a human.

進行咗首次人體輸血

Denis transfused sheep’s blood into Antoine Mauroy,

Jean-Baptiste 將綿羊血 輸畀 Antoine Mauroy

a man likely suffering from psychosis,

Antoine 疑似患有精神病

in the hopes that it would reduce his symptoms.

Jean-Baptiste 希望 輸血可以減輕佢嘅症狀

Afterward, Mauroy was in good spirits.

之後，Antoine 嘅精神狀態良好

But after a second transfusion, he developed a fever,

但係第二次輸血之後 佢開始發燒

severe pain in his lower back, intense burning in his arm,

同時下背部有劇烈疼痛 而手臂好似燒著咁

and he urinated a thick, black liquid.

而且排出一種濃稠、黑色嘅液體

Though nobody knew it at the time,

當時冇人知道

these were the signs of a dangerous immune response unfolding inside his body.

呢啲係佢身體有嚴重免疫反應嘅症狀

This immune response starts  with the production of proteins

呢種免疫反應一開始會產生蛋白質

called antibodies,

即係抗體

which distinguish the body’s own cells from intruders.

佢哋可以分清體內細胞同外來細胞

They do so by recognizing the foreign proteins, or antigens,

佢哋通過識別外源蛋白質

即抗原，嚟辨別外來細胞

embedded in an intruder’s cell membrane.

Antibodies latch onto the antigens,

抗體附著喺抗原表面

signaling other immune cells to attack and destroy the foreign cells.

示意其他免疫細胞 去攻擊同摧毀外來細胞

The destroyed cells are flushed from the body in urine.

而被摧毀嘅細胞經尿液排出體外

In extreme cases, the massive break down of cells

喺極端情況中細胞大量分解

causes clots in the bloodstream that disrupt the flow of blood to vital organs,

會令血液中產生結塊 阻礙血液流向重要器官

overload the kidneys, and cause organ failure.

令腎臟超負荷 導致器官衰竭

Fortunately, Denis’s patient survived the transfusion.

好彩嘅係 Jean-Baptiste 嘅病人 冇死於嗰次輸血

But, after other cross-species transfusions proved fatal,

但係，當跨種族輸血 被證實會致死時

the procedure was outlawed across Europe,

輸血喺歐洲被視為非法行為

falling out of favor for several centuries.

幾個世紀都唔受歡迎

It wasn’t until 1901 that Austrian physician Karl Landsteiner

直到 1901 年 奧地利物理學家 Karl Landsteiner

discovered blood types,

發現咗血型

the crucial step in the success of human to human blood transfusions.

呢個發現係人與人輸血嘅關鍵一步

He noticed that when different types were mixed together, they formed clots.

佢發現當唔同類型嘅血混合時 就會發生結塊

This happens when antibodies latch on to cells with foreign antigens,

因為抗體依附著喺 帶有外來抗原細胞上面

causing blood cells to clump together.

造成咗細胞聚集

But if the donor cells are the same blood type as the recipient’s cells,

但如果供體細胞同受體細胞 係同一個血型

the donor cells won’t be flagged for destruction, and won’t form clumps.

供體細胞就唔會受到攻擊 亦唔會形成聚集

By 1907,

到 1907 年

doctors were mixing together small amounts of blood before transfusing it.

輸血之前，醫生會先將少量血混合

If there were no clumps, the types were a match.

如果冇出現細胞聚集 咁血液就配對成功

This enabled them to save thousands of lives,

呢種方法令醫生拯救咗無數條生命

laying the foundation for modern transfusions.

為現代輸血奠定咗基礎

Up to this point, all transfusions had occurred in real time,

直到呢個時候為止 全部輸血都係實時嘅

directly between two individuals.

直接喺兩人之間進行

That’s because blood begins to clot almost immediately

係因為血液幾乎一接觸空氣

after coming into contact with air—

就即刻會發生凝結——

a defense mechanism to prevent excessive blood loss after injury.

呢種防禦機制係用嚟防止 防止受傷之後嘅過度失血

In 1914, researchers discovered that the chemical sodium citrate

1914 年，研究人員發現 化學物質檸檬酸鈉

stopped blood coagulating by removing the calcium necessary for clot formation.

可以通過移除凝結所需嘅鈣 令血液停止凝固

Citrated blood could be stored for later use—

經檸檬酸鈉處理嘅血液可以待用——

the first step in making large scale blood transfusions possible.

首次令大量輸血成為可能

In 1916, a pair of American scientists found an even more effective anticoagulant

1916 年，兩位美國科學家發現 一種更加有效嘅抗凝劑

called heparin, which works by deactivating enzymes that enable clotting.

肝素——佢可以停用導致凝結嘅酵素

We still use heparin today.

宜家我哋依然用緊肝素

At the same time,

與此同時

American and British researchers developed portable machines

美英兩國嘅研究人員 開發咗便攜式機械

that could transport donor blood onto the battlefields of World War I.

可以將血液運送到 第一次世界大戰嘅戰場

Combined with the newly-discovered heparin,

同新發現嘅肝素結合

medics safely stored and preserved liters of blood,

醫療兵得以安全咁貯藏多升血液

wheeling it directly onto the battlefield to transfuse wounded soldiers.

並將血液直接運去戰場為傷兵輸血

After the war, this crude portable box would become the inspiration

戰後，呢種原始嘅便攜箱

for the modern-day blood bank, a fixture of hospitals around the world.

就係全球每間醫院必備嘅 現代血庫嘅前身