Presentation Speech by Professor J. Åkerman, member of the Nobel Committee for Physiology or Medicine of the Royal Caroline Institute, on December 10, 1912

Your Majesty, Your Royal Highnesses, Ladies and Gentlemen.

The Staff of Professors of the Royal Caroline Institute has awarded the Nobel Prize in Physiology or Medicine to Doctor Alexis Carrel of the Rockefeller Institute, New York, for his work on suturing of vessels and transplantation of organs.

If a limb is to live, its constituent cells must be nourished by blood. If a band is wound round the lower part of the leg, and left for some time, the foot and the part of the leg adjoining it will die; if a blood clot or a thread constricting the vessel interrupt the circulation in the great artery of the groin, this may lead to a change in colour, to a cooling, and finally, to gangrene in the lower regions of the leg. If a knife-thrust or rifle bullet sever this artery, the haemorrhage can certainly be stopped with a tourniquet, but the danger remains that gangrene may attack the leg. Accordingly, the search had been going on for a long time for methods of closing a wound in the wall of a blood vessel without interrupting the circulation of blood, and, if the vessel were cut in two, of reuniting the edges of the wound so as to restore the circulation. For a repair of this kind, use was made primarily of sutures, but also of tubes of bone, absorbable metal, silver or gold, and these were either put into the damaged artery or the artery was put into them. These and yet other procedures, however, gave very uncertain and variable results. Alexis Carrel was the first person, as a result of work begun some ten or twelve years ago in Lyon, to invent a better and more reliable method of sewing vessels together again. The French doctor, when he made a suture, enlarged the opening using three retaining stitches located at equidistant points which converted the round opening into a triangular one, following which he stitched the walls together again edge to edge with fine silk threaded on to ordinary needles, which were very fine and round.

This method proved to be reliable and effective insofar as it protects against post-operative haemorrhages and embolisms, but its greatest merit was that it did not produce any stricture at the site of the suture. From the time of his first publication – in the Lyon Médical of 1902 – Carrel was able to describe attempts at replacing and reconstructing sections of damaged vessels by his method of suture, as well as the successful transplantation of whole organs (thyroid gland and kidney) to a different place in the same animal, or from one animal to another. In the course of his activities at the Hull Laboratory in Chicago, and at the Rockefeller Institute of New York, he continued to experiment and perfect his method, which has been applied successfully in many other places. He showed that suturing the ends of two vessels can be carried out not only on relatively large vessels but also on those with a diameter less than that of a match. He succeeded in replacing a section of artery with a piece of vein of the same length; he patched up holes in the wall of a vessel with pieces taken from another vessel, with pieces of sclerotic membranes, with portions of vessels, removed from other animals, indeed even with a tube of ordinary rubber. The results have proved satisfactory when examined months and years later. Parts of the aorta – in front of the spinal column – have also been replaced with different sections of vessels, and the animals treated in this way have survived in perfect health for two, three, four years after the operation.

So that he would always have material at his disposal for replacing sections of vessel, Carrel experimented in the preservation and use of such sections: kept in a refrigerator, in physiological salt solution, and in Locke’s solution, and finally in vaseline on ice, these tissues were found to be in perfect condition months later. In contrast, sections of vessel sterilized – and killed – by boiling, or indeed with formaline-glycerine or by any other method, proved to be unusable. By persistently practising and developing his method of suture Carrel was able to restore the circulation in complete organs which he had excised, or had replaced with other similar organs removed from another animal. Arteries and veins are sewn to the arteries and veins of the organ. The blood will then circulate by its normal routes through the transplanted organ, whose cells – once the circulation is resumed – carry on living and functioning as before.

Without reestablishing the circulation in this way, only fairly small pieces of tissue can be transplanted successfully from one person to another; usually groups of cells which have been transplanted in this way break down and disappear fairly rapidly. This is not so when Carrel’s method of suture is used. In this way, half the thyroid gland, the spleen, ovaries, one kidney, both kidneys even, could be transplanted from one animal to another or cut out and sewn back in their old place, still surviving and fulfilling the task required of each organ in the body’s economy. In nine out of fourteen cases in which the kidneys were excised, rinsed with streaming water and then sewn back in again, the animals lived for a long time after the operation. A dog, from whom both kidneys were first removed, one being then replaced, died two and a half years later of a quite unrelated intestinal illness; the transplanted kidney was found on examination to be normal and functional.

Using the same method, Carrel also replaced an animal’s paw with one taken from another animal, and put an amputated limb back: he saw the limb survive and knit together with the body. These experiments and a host of others have been controlled in repeated trials as much by Carrel as by his disciples in various countries.

So what lessons can we draw from these experiments on animals with regard to similar operations on humans?

Many surgeons have already resorted to Carrel’s techniques for healing local lesions in vessels, and some have succeeded in replacing a damaged section with a length of vein taken from the same person. This method has also been used in blood transfusions. The artery at the healthy person’s, the donor’s, wrist is cut, and the proximal end is sewn to a vein in the patient’s arm or leg. Blood then flows directly from the donor’s vessels into those of the patient. This operation has saved the life of a number of people, in isolated cases.

Carrel further showed that it was possible to divert the circulation in an organ, even in one of the limbs, thus facilitating or reestablishing the flow of blood. Where arteriosclerosis, for example, was obstructing the flow of blood in the leg arteries, this reversion of the circulation has been tried, and, in a fair number of cases, it has been possible in this way to avoid, even to cure, the onset of gangrene in the leg.

On the other hand, the experiments in which Carrel successfully transplanted whole organs or limbs from one animal to another have not found any application in man. For one thing, healthy kidneys, spleens and limbs are hardly ever available to the surgeon, and, for another, the experience we have gained with animals has taught us that organs transplanted from one animal to another usually degenerate in their new owners, often shrivelling up after a variable length of time, and ceasing to function. As for preserving similar material – organs or limbs – from a healthy person, in order to use them when a sick or wounded person should have need of them, our knowledge does not yet extend as far as this.

Among workers of note in the field of medicine, who in our time through their experiments on animals have endeavoured to increase the ways at our disposal of curing the wounds and diseases which afflict our own human kind, the name of Carrel is to be heard more and more frequently, and has won great renown. The new ways he has opened up of protecting threatened tissues and of replacing damaged or harmful tissue with tissue that is healthy and alive are so remarkable and the results obtained so marvellous that the Caroline Institute considers itself to be acting in complete conformity with the fundamental purpose of the great benefactor’s will in awarding Carrel the greatest distinction of present-day medicine, the Nobel Prize.

Doctor Carrel. The Caroline Institute has awarded you this year’s Nobel Prize for Medicine for your work on the suture of vessels and organ transplantation.

Sir. You have achieved great things! You have invented a new method of suturing lesions in blood-vessels. By virtue of this method, you ensure a free flow at the site of the suture, and at the same time you prevent post-operative haemorrhage, thrombosis and secondary stricture. Thanks to the same method, you are able to reconstruct the vascular pathway, to replace a segment removed from the patient with another segment taken from another part or from another person.

You have examined what useful ways and means there are of preserving the sections of blood-vessel in a condition such that they may be used later. Thanks to your method, you transplant whole organs: a lobe of a thyroid, the ovaries, the spleen, a kidney, both kidneys indeed, and you have proved that these transplanted organs can survive and carry out their special functions. In addition, you have transplanted whole limbs.

You are successful with the boldest and most difficult operations. You have increased the scope for surgical intervention in humans, and proved once more that the development of the applied science of operative surgery depends on the lessons it learns from animal experiments.

What then are the causes of your success?

First, you have set yourself a definite target, and have pursued it without respite and by all means.

Then your steady, sensitive fingers have acted as very sure, obedient instruments for your intellect, and all the procedures you have used for these complex operations are distinguished by their astonishing appropriateness and simplicity.

Finally, the clear, bright intelligence which was the patrimony you received from your country – from France, in whose debt humanity stands for so much that is valuable – was allied to the bold, resolute energy of your adopted country, and these marvellous operations, of which I have just spoken, are the manifest result of this happy collaboration.

Sir. The Caroline Institute, and, I dare say, the whole medical world, offers you today, through the medium of my voice, its congratulations and compliments.