April 25, 2024

MOSIHUR BLOG

TECHTUNES WORLD

A heart-lungmachine, so to speak

6 min read

This World Shared Practice Forum will differfrom our typical World Shared Practice Forums. This video is the first installment of our”History of Medicine” series in which we will be discussing the history of modern medicinewith experts from around the globe. Unlike most World Shared Practice Forums, there willbe no discussion questions during this video.

I wonderif I could begin by asking you about your career. Many of my colleagues around the worldwould be very interested to know what were the influences that guided you through yourcareer, what brought about these changes. And I know in particular that you trainedand went to medical school in Guatemala, but then found yourself doing surgery in Minnesota.And I wonder if we could talk about that transition, what drew you to Minnesota, and really thestart of your surgical career. Well, as a medical student, I was aware that the heartwas the only organ that had not been accessible to surgery. I mean, I was interested in surgeryin general. And I receive the “New England Journal of Medicine” at the time as a medicalstudent.

However, if you would like to ask a questionor leave a comment, please feel free to do so at any time. Thank you, and we hope youenjoy this video. I’m Dr. Jeff Burns, Chief of Critical Care at Boston Children’s Hospitaland Harvard Medical School. And we’re very pleased to have with us today Dr. Aldo Castaneda.Dr. Castaneda was, for 20 years, the William Ladd Professor of Surgery here at Boston Children’sHospital, and also the Surgeon-in-Chief during that time. For the past 15 years, Dr. Castanedahas developed and lead a clinic for cardiovascular surgery of children in Guatemala and CentralAmerica. Dr. Castaneda, it’s a privilege to have you with us today.

There, I learned that there was– particularly what I read– was this groupin Minnesota who somehow picked up the role of the central advances in intracardiac surgery,they developed. The first person who was really instrumental in developing a cardiopulmonarybypass system was Dr. Gibbon. He had been a fellow in Philadelphia, I think it was Jefferson.And for a while, had a rotation at Mass General in Boston. And there, one night he was oncall and there was a young lady who had broken her leg, if I remember correctly, and shedeveloped a pulmonary embolism. And Dr. Gibbon was on call, spent all night trying to helpher. And she died. And at the autopsy, they found that the stratification of the pulmonaryartery was totally occluded by a clot. And he thought that– otherwise, it was a normalheart that was secondary to her fracture– that if one could develop a system, a heart-lungmachine, so to speak, that would take over the function of the heart and the lungs. Duringthat time, you could operate on the heart, take out that clot, she would have survived.Now, at that time, there was a Trendelenburg operation which very few people had had successwith, extracting pulmonary emboli, and so on.

But that became a very interesting history.We don’t have time to go into it. But he spent 20 years of his life in the cellar of MassGeneral. The surgical hierarchy at the time was not particularly interested, and thoughtthe guy was a little bit out of shape. But he did get a little room in the cellar ofMass General to do some experiments. And Harvard Medical School gave him a grant. Not a lot,but some grant. And he started in the early 1930s to work on a heart-lung machine. Itwas quite interesting. Alone, without much enthusiasm of the Dr. Churchill, I think,was the chief of surgery. He thought that was nonsense. But he worked. Kept on working.

There was a nurse who helped him. They were there in the cellar every night. So anyhow,they got married eventually. And also, eventually, he did the first open heart surgery usingan artificial heart-lung machine which was green oxygenated type. He did six operations,of which only one patient survived. And there were others also. And the mortality for usingan artificial heart-lung machine at that time was about 95%. There was only one survivor.That created a very negative atmosphere in the cardiological world.

And Gibbon– WaltLillehei told me that– Gibbon offered himself to lead a movement through Congress of theUnited States to ban or have a moratorium on open heart surgery for indefinite timeperiod. Really? Fortunately, it didn’t succeed somehow. Another young group of surgeons atthe University of Minnesota– and so where Minnesota comes in– led by Walt Lilleheiand Dr. Richard Varco had a different idea, which was interesting. They developed in thelab so-called cross circulation. And Richard took a human donor, if you want to use thatword, and put cannulus through the femoral artery and femoral vein. Take out from thevenous system of the recipient of the patient. Pump it into the femoral vein of the donorwith another catheter in the femoral artery that was threaded up to the abdominal aorta.You get red blood out, oxygenated blood out from the donor, and pumped it into a tieredsystem of the recipient.

So it was called controlled cross circulation. 1953. And theydid 46 cases, 46 operations on patients. They did for the first time, close the ventricularseptal defect. Atrial septal defect. Tetralogy of Fallot. And they had a few– I think therewere three– complete AV canals. The mortality was high. But nevertheless, they proved. Becausethat was the question. Why did using the heart-lung machine, why did they all die? They provedthat one could do an extra corporeal circuit and open the heart, fix something, and thatthe heart would tolerate that. Was the donor typically a parent? I know in one case– Thedonor was mother or father.

Always mother or father. Did any of the donors– No. Oneof the donors, the circuit had some problem. There was some embolism with some neurologicdeficit, but not severe. But it was, of course, it was clear to everybody. It was not a permanentarrangement, but it was a major step against the pessimism of those in the world at thattime about the feasibility of open heart surgery. It did show that you could operate on theheart. At the Mayo Clinic, John Kirklin had gone to medical school at Harvard, whose fatherwas a professor of radiology at the Mayo Clinic. He had after that gone back to Rochester,did his training, and stayed on the staff, became interested in heart surgery.

And hisclassmate was Gibbon here at Harvard. So he went to the engineer of the Mayo Clinic, Johnson.Jonas. He went to Philadelphia and looked at the apparatus that Gibbon had built. Theylooked at it. They found it was somewhat complicated. Too much server mechanisms involved. Anyhow,they modified it. Came up with a Mayo-Gibbon oxygenator.

It was the Rolls Royce at thetime. Very expensive, but they could do it. Mayo Clinic was richer. Went back to Rochesterand started their effort of open heart surgery using a Mayo-Gibbon pump oxygenator. In themeantime at the University of Minnesota, 90 miles apart– Minneapolis and Rochester, they’re90 miles apart. They then went away from the cross circulation using the human donor, anddeveloped a bubble oxygenator. Dick DeWall developed a bubble oxygenator, which in away was a version of what the physiologists had used in the 19th century for organ profusions.For direct blood gas interface. And that was in 1954, 1955.

And then they started theirseries of open heart surgery using the so-called bubble oxygenator, which was plastic. Thetotal cost of that was unbelieveable. And unbelieveably they bought the plastic tubingsfor, I think it was at that time, $30 or something like that. So there was a significant difference.And cheap. And that really popularized cardiac surgery. But for two, two-and-a-half years,the only open heart surgery in the world was done between the Mayo Clinic and the Universityof Minnesota group. Wow. Interesting.

Leave a Reply

Your email address will not be published. Required fields are marked *