Therapy: The Liver and the Baboon

The diseased liver poses some of medicine’s toughest problems. Surgeons have tried transplantation, but the process is incredibly difficult, and the survival record so far is only 13 months (TIME, Sept. 6). With varying degrees of success, doctors have 1) used massive blood transfusions, 2) passed the patient’s blood through an excised but still functioning pig’s liver, and 3) even connected a patient’s bloodstream with another human’s, thus letting the volunteer’s liver function for both bodies. But the results have been spotty, at best. Now a team of South African surgeons, including Heart Transplanter Christiaan Barnard, have managed to halt a severe case of liver failure by hooking the bloodstream of a dying woman to that of a live baboon.

When the liver fails completely, the results are so predictably fatal that doing anything that might provide relief is better than doing nothing. The healthy liver not only performs dozens of vital metabolic chores, it is also an essential purification plant, purging toxic wastes from the bloodstream. Even diseased, the liver has a remarkable capability: it can often regenerate its damaged cells and rebuild lost tissues. The problem is to keep the patient alive while the liver is taking a recuperative holiday.

Blood Exchange. With all this in mind, the South Africans confronted the case of Mrs. Mary Voogt, a 29-year-old nurse and mother of two children who was brought to Cape Town’s Groote Schuur Hospital last July in a deep coma. Only a few days before, she had suffered a miscarriage. Early in her pregnancy, she had contracted severe hepatitis, and it left her liver badly damaged. Doctors tried seven blood exchanges, giving her body an entirely new supply of blood each time. Yet there was no noticeable improvement, and finally they turned in desperation to the baboon.

Their decision was not reckless. Baboons are so prolific and hungry for farmers’ crops that they are legally classified as vermin in South Africa. Highly developed primates and kin to man, baboons are also highly useful in medical research. Only recently, a baboon’s cornea was successfully grafted onto a man’s eye. A pig’s liver, although it tolerates human blood, is not nearly so sophisticated as the baboon’s.

Equalizing the Flow. Unlike previous work with pig organs, Groote Schuur’s procedure involved not only the animal’s liver but its entire circulatory system, heart and all. And the doctors did not kill the animal first. To prepare the baboon, a robust 57-lb. male, they put it under an anesthetic, then replaced its entire blood supply with human blood of the same type as Mrs. Voogt’s. Nearly five hours later, after the animal’s heartbeat and circulation had stabilized, the baboon was ready for the hookup with Mrs. Voogt. The surgeons deftly led a tube from an artery in the woman’s right arm, above the pulse point, to a vein in the baboon’s groin. With a second tube, they linked an artery in the baboon’s groin to a vein in the woman’s arm. When the setup was in place, the doctors released the clamps that opened the two-way circuit.

The surgeons let the blood circulate freely between woman and beast for almost two hours. During that time, the woman’s declining blood pressure indicated that her stronger heart was pumping more blood into the baboon than the baboon was able to send back. But the doctors were prepared for that difficulty. To keep the volume of blood in the woman from dwindling to a dangerously low level, they introduced two small pumps and two wells into the system. With that equipment, they were able to equalize the flow of blood, using the pumps to help the baboon match Mrs. Voogt’s heartbeat. The cross circulation was allowed to continue for four more hours before the doctors again tied on the clamps.

Out of Coma. The entire process went off with the usual precision of Groote Schuur’s surgical efforts. Three days after the blood exchange, the woman came out of her coma, recognized her husband, and was soon responsive to commands. Her progress continued steadily, so that by the end of August she was able to resume a normal diet. Then, a fortnight ago, she died. At week’s end there was still no announcement from South Africa giving the exact cause of death. But the pioneering procedure was at least a partial success. Mrs. Voogt’s six weeks of additional life were in themselves proof that her liver had resumed its vital functions. And there was no doubt that the baboon had given its all.