Robotic kidney transplant opens door to patients with a higher BMI

Patients with a BMI higher than 40 are often rejected due to high risk; less-invasive robotic kidney transplants can help them survive and thrive.
Feb. 7, 2022

UCHealth University of Colorado Hospital on the Anschutz Medical Campus (UCH) has become the nation’s fourth medical center – and the first west of the Mississippi – to perform a kidney transplant on a high-BMI patient using a surgical robot.

Jason Lang and Lisa Matlock. Lisa donated the kidney that enabled Colorado’s first robotic kidney transplant on a high-BMI patient.
Jason Lang and Lisa Matlock. Lisa donated the kidney that enabled Colorado’s first robotic kidney transplant on a high-BMI patient. Photo by Cyrus McCrimmon for UCHealth.

The surgery, performed by University of Colorado School of Medicine transplant surgeon Dr. Thomas Pshak on Nov. 17, was the culmination of two years of preparation, and it bodes well for those who otherwise wouldn’t be able to get kidney transplants at all.

Jason Lang, whom Pshak transplanted with a kidney from Lisa Matlock, Lang’s longtime partner, represents a growing group of patients for whom excessive body weight made traditional open kidney-transplant surgery too risky.

Lang, 46, had a body mass index (BMI) of 43 prior to the surgery, though that figure was inflated by kidneys that weighed about 15 pounds each – about 50 times more than usual. The financial services director was born with a genetic mutation that led to polycystic kidney disease, a condition that can turn a fist-sized kidney into something as large as an NFL football. It brought the early deaths of his father and his grandfather.

“I knew I was going to need a transplant or dialysis eventually,” Lang said.

Dr. Thomas Pshak
Dr. Thomas Pshak

By early 2020, a spike in his creatinine levels meant that “eventually” would come years before he was expecting it. He and his nephrologist kept tabs on his declining kidney function; by June 2021, it was clear that he was on the precipice of needing dialysis. Lang reached out to the UCHealth Transplant team to set the wheels in motion.

There would be two hurdles. One is finding a donor – there’s a roughly six-year waiting list for a kidney from a deceased donor unless one can find a match independently from a living donor. That would turn out to be easy for Lang: Matlock offered to donate one of her kidneys, and against long odds, she proved to be a match. The second hurdle was his weight.

Kidney transplant and high BMI

Kidney transplant complications increase with girth mainly because, the more belly fat there is, the longer and deeper the incision is required to provide enough access to do the transplant. (Donor kidneys are implanted in the lower abdomen well below the kidneys and next to the bladder, plugging into large leg vessels for blood supply.) That elevated risk makes it exceedingly hard for those with BMI over 35 to get listed for a kidney transplant.

Pshak, the surgeon, recognized a dilemma here, and one that will only get worse as the population of those with a BMI over 40 – that’s a 5-foot-4 inch, 232-pound woman or a 5-foot-9, 270-pound man, as examples – grows to nearly a quarter of the U.S. population by 2030. Also, while dialysis may keep people alive long enough for a transplant, it’s a time-consuming, energy-sapping process, and those on dialysis often lack the zip to lose significant weight.

“When you’re tethered to a dialysis machine, and your energy level is horrible, and you’re dealing with muscle-wasting, it’s virtually impossible to ask someone to lose 50 pounds,” Pshak said. “And so, you’re essentially giving them a death sentence, because dialysis is only going to last so long before they get complications and ultimately die.”

couple holding hands. Lang recently became the first patient with a high BMI to get a kidney transplant in Colorado because of robotic surgery.
Lang’s polycystic kidney disease meant that a kidney transplant was inevitable. But it came much sooner than he and Matlock expected. Lang recently became the first patient with a high BMI to get a kidney transplant in Colorado because of robotic surgery. Photo by Cyrus McCrimmon for UCHealth.

Pshak considered that unjust, and he was in a unique position to do something about it. He is fellowship-trained in liver, kidney and pancreas transplants, but he is also a board-certified urologist, a field in which robotic surgery is heavily used. Starting about two years ago, with the support of Dr. Elizabeth Pomfret, who leads the CU School of Medicine’s Division of Transplant Surgery and the Colorado Center for Transplantation Care, Research and Education (CCTCARE), Pshak spent countless hours of his research time and his own time – nights and weekends on top of his surgical day job – refining his skills on the Da Vinci Surgical System.

The system translates the surgeon’s gestures into electronic commands whisked through a thick cable to the surgical robot with gray arms sheathed in clear plastic for infection control. The robot reconstitutes the surgeon’s subtle motions into even smaller robotic actions while removing the natural jitter of even the steadiest human hands. The surgeon’s console provides immaculate 3-D visualization while the monitors around the operating table and high on an operating room wall display the results at the same 10-times magnification that the system affords the surgeon. The robot’s three surgical arms and camera need only ¼-inch incisions each, and the kidney to be transplanted can be inserted through an incision of about two-and-a-half inches around the belly button, Pshak says. An open procedure on a large patient, he says, typically involves a 10-inch incision in a less-than-ideal location near the front side of the hip.

Speed matters with kidney transplants outcomes

Dr. Thomas Pshak gives a thumbs-up at the Da Vinci console before Jason Lang’s robotic kidney transplant on Nov. 17, 2021. Photo courtesy of Thomas Pshak.
Dr. Thomas Pshak gives a thumbs-up at the Da Vinci console before Jason Lang’s robotic kidney transplant on Nov. 17, 2021. Photo courtesy of Thomas Pshak.

Pshak visited with Dr. Atsushi Yoshida at the Henry Ford Medical Center in Detroit and Dr. Enrico Beneditti at the University of Illinois Chicago, two of the pioneers of U.S. robotic kidney transplantation among severely obese patients. He and his surgical OR team, including fellow transplant surgeon Dr. Trevor Nydam, visited Da Vinci maker Intuitive Surgical in Sunnyvale, Calif., to refine and optimize the surgical technique and surrounding support involved in a robotic transplant. Those refinements included such details as using super-thin Gore-Tex thread with needles half the size of those preferred for manual surgery, learning the ropes of new robotic instruments, and reducing the size of the opening needed to introduce the kidney.

Speed was the overriding imperative: The faster one can implant the donor kidney, the better the chance of the surgery’s success, Pshak says. That’s because, with every minute the kidney’s out of the ice and not getting blood, it has the potential to lose a bit of function. His target was to have the kidney implanted within 30 minutes of it appearing in the operating room, which is the speed surgeons shoot for with open transplants.

By the time CU School of Medicine nephrologists Dr. Bruce Kaplan and Dr. Monica Grafals brought Jason Lang to Pshak’s attention, the team was ready to go. In Lang, Pshak saw a patient who was young, otherwise healthy and who could be spared the challenges of dialysis. Exhaustive testing had confirmed that Matlock’s kidney was as compatible with Lang’s body as she was with him as a person. On a Wednesday morning in mid-November, she went into one OR and he into another. Dr. Kendra Conzen safely removed her kidney and placed it on a tray of ice to be carried to the Da Vinci operating room. There, Nydam prepared the kidney and squeezed it into Lang’s abdomen, where Pshak’s three robotic proxy-arms took it and, in about a half hour, held and sewed it into place, spacing tiny sutures at millimeter intervals at a pace and precision that only muscle memory can muster.

The little white organ puffed up, went kidney-bean red, and immediately began to make urine. The surgery was a success.

Post transplant: ‘A lucky human’

Two months later, Lang and Matlock entertained questions about their respective experiences with the transplant. Lang was up and walking the day after surgery – Matlock’s room at UCH being among the first destinations.

“The difference in pain and recovery speed was so pronounced between the two of us,” Matlock said. “When I was in the hospital, they gave me a little button that would dispense Dilaudid, and it’s not taking the edge off the pain. And here he’s booking down the hospital floor to see me.”

“I tolerate pain better,” Lang teased.

Seeing how swiftly her partner recovered, Matlock’s only regret, she says, is that her kidney donation wasn’t done robotically, too. Photo by Cyrus McCrimmon for UCHealth.
Seeing how swiftly her partner recovered, Matlock’s only regret, she says, is that her kidney donation wasn’t done robotically, too. Photo by Cyrus McCrimmon for UCHealth.

“He had a foot surgery and you would have thought you’d have chopped off his leg,” Matlock quipped.

Lang has lost about 30 pounds since the surgery, which he attributes to changes in his diet and “having a kidney that works.” The naps he found himself taking after going for walks or hikes are no longer part of his afternoons. Early in the day, his improved health is vivid. Before the surgery, Matlock was the only one up at 5 a.m.

“I used to have my nice, quiet mornings – pay the bills, sip coffee, play with the dogs,” she said. “Now, Jason has so much energy, he’s up and, like, ‘Maybe I’ll change the water in the fish tank. Maybe I’ll clean up the kitchen.’”

Matlock’s recovery has gone more slowly. She has no regrets about donating the kidney. She only wishes she’d had the removal done robotically, too.

“The difference in pain and recovery speed was so pronounced between the two of us,” she said.

Lang is grateful for his partner’s generosity.

“I may not have been there if Lisa wouldn’t have been a match, and I would have had to wait seven years,” he said. “There are a lot of factors at play here that made me a lucky human.”

Pshak and the OR team that enabled the robotic kidney transplant were big factors also. Pshak intends Lang’s surgery to be the beginning of a practice that can transplant perhaps 50 kidneys a year in people who otherwise wouldn’t pass muster simply because of their weight. He led a second successful robotic kidney transplant on Dec. 26, and he’s aiming for 15 to 20 of them in 2022.

“The reason I put in all the time and effort was because I really believe in this operation for the severely obese,” Pshak said. “Just because you’re overweight, I don’t think you should be denied a transplant.”

About the author

Todd Neff has written hundreds of stories for University of Colorado Hospital and UCHealth. He covered science and the environment for the Daily Camera in Boulder, Colorado, and has taught narrative nonfiction at the University of Colorado, where he was a Ted Scripps Fellowship recipient in Environmental Journalism. He is author of “A Beard Cut Short,” a biography of a remarkable professor; “The Laser That’s Changing the World,” a history of lidar; and “From Jars to the Stars,” a history of Ball Aerospace.

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