The Great Events by Famous Historians

The idea of preserving the life of greater or lesser parts of an organism occurred at about the same time to a number of persons, and though the ends in view have been quite different, the investigations have led to essentially similar results. The surgeons who for a long time have transplanted various organs and grafted different tissues, bits of skin among others, have sought to prolong the period during which the grafts may be preserved alive from the time they are taken from the parent individual until they are implanted either upon the same subject or upon another. The physiologists have attempted to isolate certain organs and preserve them alive for some time in order to simplify their experiments by suppressing the complex action of the nervous system and of glands which often render difficult a proper interpretation of the experiments. The cytologists have tried to preserve cells alive outside the organism in more simple and well-defined conditions. These various efforts have already given, as we shall see, very excellent results both as regards the theoretical knowledge of vital phenomena and for the practise of surgery.

It has been possible to preserve for more or less time many organs in a living condition when detached from the organism. The organ first tried and which has been most frequently and completely investigated is the heart. This is because of its resistance to any arrest of the circulation and also because its survival is easily shown by its contractility. In man the heart has been seen to beat spontaneously and completely 25 minutes after a legal decapitation (Renard and Loye, 1887), and by massage of the organ its beating may be restored after it has been arrested for 40 minutes (Rehn, 1909). By irrigation of the heart and especially of its coronary vessels the period of revival may be much prolonged.

The first experiments with artificial circulation in the isolated heart were made in Ludwig's laboratory, but they were limited to the frog and the inferior vertebrates. Since then experiments on the survival of the heart have multiplied and become classic. Artificial circulation has kept the heart of man contracting normally for 20 hours (Kuliabko, 1902), that of the monkey for 54 hours (Hering, 1903), that of the rabbit for 5 days (Kuliabko, 1902), etc. It has also enabled us to study the influence upon the heart of physical factors, such as temperature, isotonia; chemical factors, such as various salts and the different ions; and even complex pharmaceutical products. Kuliabko (1902) was even able to note contractions in the heart of a rabbit that had been kept in cold storage for 18 hours, and in the heart of a cat similarly kept after 24 hours. The other muscular organs have naturally been investigated in a manner analogous to that which has been used for the heart; and for the same reason, because it can be readily seen whether or not they are alive. The striated muscles survive for quite a long time after removal, especially if they are preserved at the temperature of the body and care is taken to prevent their drying. By this method many investigations have been made of muscular contractions in isolated muscles. Landois has noted that the muscles of a man may be made to contract two hours and a half after removal, those of the frog and the tortoise 10 days after. Recently Burrows (1911) has noted a slight increase in the myotomes of the embryo chick after they have been kept for 2 to 6 days in coagulated plasma.

Non-muscular organs may also survive a removal from the parent organism, but the proofs of their survival are more difficult to establish because of the absence of movements. Carrel (1906) grafted fragments of vessels that had been in cold storage for several days upon the course of a vessel of a living animal of the same species; in 1907 he grafted upon the abdominal aorta of a cat a segment of the jugular vein of a dog removed 7 days previously, also a segment of the carotid of a dog removed 20 days before; the circulation was reestablished normally; these experiments have, however, been criticized by Fleig, who thinks that the grafted fragments were dead and served merely as supports and directors for the regeneration of the vessels upon which they were set. In 1909 Carrel removed the left kidney from a bitch, kept it out of the body for 50 minutes, and then replaced it; the extirpation of the other kidney did not cause the death of the animal, which remained for more than a year normal and in good health, thus proving the success of the graft. In 1910 Carrel succeeded with similar experiments on the spleen.