Recent Comments

Tomoaki Kato Performed a 23-hour Rare 'Ex Vivo Surgery'

Written By UNDER MAINTENANCE on Monday, January 10, 2011 | 6:35 AM

With some tumors, you don't know where to start. They grow into giant, bulbous burls before the doctors even find them. They engulf organs and become enmeshed in the connecting web of blood vessels to the point that it all seems inextricable, like a rooster caught in a fishnet. Sometimes it's difficult to even see the whole tumor through the tangle, let alone think about how to eradicate it.

Hippocrates, father of medicine, isn't credited with the invention of any lasting medical technology. He is credited with having common sense. And so Hippocrates would have loved Tomoaki Kato, a soft-spoken forty-seven-year-old man from Japan who has figured out how to remove the kind of grotesque tumor that smothers a person's insides: Take the insides out. Everything. Sever the arteries, lift the organs en bloc onto a table, cut and scrape the tumor away, and put the organs back in. Ex vivo surgery, it's called. "Out of the living body." Not long after the first kidney transplants, in the 1950s, Kato says, doctors experimented with ex vivo repairs of traumatized kidneys. Decades later, at Miami's Jackson Memorial Hospital, Kato helped pioneer mass organ transplants — remove someone's entire abdomen, put in someone else's. "Instead of repairing each part, you replace the whole engine," Kato says. These two precedents were in his mind when he pioneered extreme ex vivo, which Kato has performed three times, all since 2008. The difference is that the same organs are reimplanted, so there's no chance that the patient will reject them. Still, there can be complications. One patient, Robert Collison, died in April, four months after the procedure.

Ex vivo surgery is expensive, time-consuming, and difficult, no question. But Kato points out that multiorgan transplants that once took thirty hours can now be done in six — point being, you get better. Most important, whereas there was once nowhere to even begin attacking tumors so overgrown and horrid, Kato has found a way to obliterate them with a single procedure — even if, for now, it can take all day.

Ex Vivo Surgery: A Timeline

Over twenty-three hours in February 2009, Kato performed a rare "ex vivo" surgery on Heather McNamara, seven, of Long Island, New York. All of her abdominal organs were removed, a large tumor was excised from them, and some of the organs were reimplanted. She's doing fine today.

7:45 A.M.: Anesthesia
For the next two hours, surgeons prepare Heather for the surgery by inserting tubes to monitor vital signs and handle transfusions, if necessary.


9:45 A.M.: Jugular-Vein Harvesting
Heather has a large tumor that's entangled with her abdominal organs and the blood vessels connecting them. When Kato removes the organs, those vessels will be discarded. So the first step is to remove from her neck and set aside a piece of Heather's jugular vein, which will later be used to reconnect the liver. Kato does this instead of using a synthetic replacement such as Gore-Tex, which has a higher clotting rate. Gore-Tex is fine for most reconnections, but for one key spot, he wants an actual vein.

11:45 A.M.: Abdominal Surgery
During this critical period, Kato examines the tumor and determines whether to proceed with the surgery, depending on what he thinks are the odds for success. "We can still stop at this point," Kato says. "This is the hardest part: Move this, move that, pull this down and up — just to figure out if you should commit to the extreme." Once he decides to go ahead, blood vessels are severed and tied off and each organ is prepared for removal.


Separating the Colon
In ex vivo surgery, Kato removes only the organs (or parts of organs) that the tumor affects, leaving intact what he can. Here, the right side of the colon is prepared for removal. The left side, untouched by the tumor, is the only abdominal organ that will remain in Heather's body while the rest are removed and the tumor cut away.


4:10 P.M.: "Out of the Living Body"
Kato removes the organs — intestines, stomach, spleen, pancreas, and liver — and places them in a basin of preservative solution over ice. (The solution, which is proprietary, is just about the only new technology that would have made it impossible to perform ex vivo surgery a hundred years ago.) Three teams of surgeons will now work simultaneously to cut the tumor off the various organs. "It's another critical moment. Once the organs are out, the clock is ticking. So to cut down the time, one surgeon is repairing the liver, another is repairing the intestine, and another is putting artificial Gore-Tex arteries in her body at the same time," to prepare to reconnect everything.



Saving the Liver
Preserving the liver is a "close call," says Kato, because the tumor is pressing against it severely. (A small portion of the liver ends up sticking to the tumor and will be discarded.) Heather's father is standing by as a live liver donor during the surgery, in case Kato isn't able to reimplant her own. Kato has not taken a break yet — he doesn't take many, but when he does, it's for a quick nap and a bit of food, often something sweet like chocolate.




8:50 P.M.: The Liver Goes Back In
While organs can function for more than ten hours outside the body, we risk circulation complications without them after about six hours. Kato removes, repairs, and reattaches (using the section of her jugular vein) Heather's liver in 163 minutes. Her stomach, pancreas, and spleen, unfortunately, are too damaged to be saved. At 9:45 P.M., the intestines are reimplanted.

Final Connections
Arteries are reconnected, the bowel is sewn in, and other reconnections are made, procedures that take hours. The esophagus, normally leading to the stomach, is instead sewn directly to the small intestine. Because the stomach is mostly just a food reservoir, humans can live without it — Heather will be able to eat relatively normally, just in smaller portions.

5:05 A.M.
The surgery is complete. Kato collapses on a couch and falls asleep.

0 comments:

Post a Comment