Open-Heart Surgery

Open-Heart Surgery
心内直视外科手术
Without a steady supply of fresh blood, without the oxygen it carries, the human brain is quickly impaired. In four minutes, brain cells, starved for oxygen, begin to die, and serious brain damage results. In another few minutes, the brain is completely destroyed.
如果没有稳定的新鲜血液和氧气供应，人类大脑很快就会受到损伤。

四分钟以后，缺乏氧气的脑细胞开始死亡，并且会造成严重的脑损伤后果。

再过几分钟，大脑就会完全被破坏。

This was the crux of a stubborn problem. The heart could not be taken out of action for more than four minutes—very little time to repair a heart defect. Until a solution could be found, operating on the open heart would be impossible.
这个顽疾问题的核心就是：心脏停止跳动不能超过四分钟——时间太短以至于不能修复心脏疾病。

除非找到一种可行的解决方法，否则心内直视外科手术是不可能的。

The two major advances pointed the way to open-heart surgery. One was hypothermia, the artificial lowering of the body temperature. Body tissues need far less oxygen when the body is chilled. A “frozen” brain, for example, requires only half as much oxygen as one with a normal body temperature of 98.6 Fahrenheit. This means it can do without fresh blood for longer than four minutes and not suffer damage. In 1950, a
Canadian professor, Wilfred G. Bigelow of the University of Toronto made this important discovery, and he immediately saw that hypothermia might give heart surgeons the chance “to operate on a bloodless heart.” With hypothermia, a surgeon could clamp off arteries leading to the heart and stop blood flowing into it. He could open the heart, drain it of excess blood, and operate in a “dry field” for more than five minutes. Two yea rs later Dr. Floyd John Lewis of the University of Minnesota tried open-heart surgery with hypothermia. The day after the operation his five-year-old patient was walking, and she was discharged from the hospital ten days later.
后来取得的两个主要进展为心内直视外科手术铺平了道路。

一个是降低体温，人工降低体温。

当身体器官处于冷冻状态时，其所需的氧气来量会大幅减少。

例如，“冷冻”大脑所需得氧气量只是正常体温98.6华氏摄氏下大脑氧气需求量的一半。

这意味着大脑不会受到损伤，也不会遭到损害，即使在超过四分钟没有新鲜血液供应的情形下。

1950年，一位多伦多大学的加拿大教授威尔弗雷德·G·比洛奇发现了这个重要的发现。

并且，他很快意识到降低体温可能给心脏手术，“没有血液的心脏手术”，带来可能性。

用降低体温的方法，外科医生可以钳住通往心脏的动脉，阻止血液流入心脏。

然后，划开心脏，排干心脏中的大量血液，然后在一块“干地”上进行超过五分钟的手术。

两年以后，明尼苏达州立大学的弗洛伊德·约翰·刘易斯医生尝试用降低体温的方法来进行心内直视外科手术。

手术后的第二天，他
5岁的病人就可以下地走路，十年后康复出院。

The future of heart surgery looked bright. But hypothermia could not be used safely in long and intricate heart surgery. During hypothermia, the heart sometimes lost its regular pumping beat. It fibrillated, or fluttered and trembled uselessly; and this fibrillation could cause death if the beat could not be restored.
心脏外科手术的前景一片光明。

但是，降低体温的做法不能安全地用于长时间、错综复杂的心脏外科手术中。

降低体温时，心脏有时会出现不规律的跳动。

心脏可能会出现肌纤维震颤，或者会出现徒劳地加速跳动和颤动。

如果心脏不能恢复正常跳动，出现的肌纤维震颤能够造成死亡。

Then came the second major advance for open-heart surgery: a machine to substitute for the heart and lungs. The heart-lung machine pumps blood like the heart. Like the lungs, it rids the blood of carbon dioxide and replenishes it with oxygen. It actually breathes and circulates blood for a heart patient in surgery. Research by many doctors helped to develop this complex device, but one man stands out. He is Dr. John H. Gibbon of Philadelphia’s Jefferson Medical College. The father of the heart-lung machine, he researched and worked on its problems for nearly twenty years.
第二个心内直视外科手术的主要进步：代替心脏和肺部的装置。

这种心肺装置可以像心脏一样，供应血液；可以像肺部一样，排出血
液中的二氧化碳，补充氧气。

实际上在外科手术中，这种装置帮助心脏病人呼吸和进行血液循环。

这种装置已经使心脏外科手术发生了彻底的变革。

许多医生的研究促进了这个复杂仪器的诞生，但是其中有一个人格外引人注目。

他就是费城杰斐逊医学院的约翰·H·吉本医生。

心肺装置之父，他从事于这个装置的研发将近二十年。

In May, 1953, Gibbon decided his heart-lung machine was ready to be used. His first patient was an eighteen-year-old girl with a serious heart condition. Between her right auricle and the left was a hole the size of a half-dollar. The girl was “plugged in” to the machine for almost half an hour while Gibbon and his team sewed up the hole. For the first time in history, synthetic device had successfully substituted for the heart and lungs in surgery.
1953年5月，吉本认为他的心肺装置已经可以在手术中使用。

他第一个病人是一位有严重心脏病的十八岁女孩。

在她左右两个心房之间，有一个半个银元一样大小的洞。

在吉本和他的医疗团队缝合洞口期间，这个女孩靠着这个装置“充电”几乎有半个小时。

人类史上第一次，人造装置在手术中成功地代替了心脏和肺部的功能。