A panel of 3 transplant surgeons who are urologists debated the pros and cons of an open vs robotic-assisted approach to kidney transplantation at the American Urological Association’s 2023 Annual Scientific Meeting in Chicago, Illinois.¹

Moderator Nicholas Cowan, MD, of Virginia Mason Medical Center in Seattle, Washington, stated that the first robotic-assisted kidney transplantation (RAKT) was performed in 2010 in the United States, whereas open kidney transplantation (OKT) has been performed since the 1950s. He cited an OPTN/SRTR annual data report indicating that in 2021, 25,487 kidney transplantations took place in the United States, including living and deceased donor transplants.²

Alberto Breda, MD, PhD, is a proponent of RAKT. He is head of the uro-oncological unit and surgical kidney transplantation team at Fundacio Puigvert, Universitat Autonoma de Barcelona and chair of the European Association of Urology’s Robotic Urology section (ERUS).

“[RAKT] was experimental. It is not nowadays. In my opinion it is here to stay and it will help more and more surgeons and our patients to get better results,” Dr Breda said.

Jeffrey Veale, MD, of UCLA Health in Los Angeles, California, is a proponent of OKT and lauded its proven track record.

“Do you want a great transplant or to be cool [by using robotics]? I would argue that kidney transplantations should probably stay open,” Dr Veale said. He argued that patients want a transplant surgeon to be like “Sully” Sullenberger, the expert pilot with years of experience who safely landed a commercial plane with passengers on the Hudson River in New York City.

Graft function

According to Dr Cowan, graft function at 1 month and 1 year after kidney transplantation appears comparable between RAKT and OKT based on the existing literature. In 2021, The Journal of Urology published a prospective cohort study of 654 patients who underwent OKT or RAKT at a single tertiary care hospital between January 2013 and December 2015.³ After matching, investigators led by Rajesh Ahlawat, MD, of Kidney and Urology Institute, Medanta – The Medicity in Gurgaon, India, found no significant differences between groups in delayed graft function or graft rejection, graft survival, and overall survival at 36 months.

While we await more head-to-head research and important guideline updates, one surgical approach to kidney transplantation may have an advantage over the other in the following areas:

Operating Room Time

One benefit of OKT is speed, according to Dr Veale. Operative time is approximately 1 hour with OKT compared with 4-5 hours with RAKT including robotic docking, he revealed. “I don’t think patients should be under anesthesia for that long,” he said. Dr Veale noted that patients experience less inflammation with shorter operations, and hospitals prefer it.

With respect to anastomotic time, Dr Cowan said it depends on the surgeon’s experience regardless of the surgical approach. He is the director of the urology residency program at Virginia Mason.

Dr Breda acknowledged that deceased donor RAKT is feasible^4,5 but requires extensive planning and logistic coordination. The robotic platform needs to be available at night and during weekends. For this reason, his RAKT surgeries have mainly involved living kidney donors because they can be scheduled in advance.

Extensive Blood Loss, Pain, and Wound Complications

In the study by Dr Ahlawat and colleagues, RAKT was significantly associated with lower rates of wound infections (0% vs 4%), symptomatic lymphoceles (0% vs 7% at 36 months), as well as reduced postoperative pain, requirement for narcotic analgesia, and blood loss, compared with OKT. Dr Cowan believes RAKT has an advantage in these areas. He noted that the typical kidney transplant patient has risk factors for wound complications, such as diabetes, older age, obesity, immunosuppression, and smoking.

Dr Breda agreed that RAKT is associated with reduced rates of early complications such as wound infection and lymphocele, but also late complications such as incisional hernia, ureteral stenosis, and graft pyelonephritis, compared with OKT. He based his conclusions on his review of several RAKT studies, such as the study by Dr Ahlawat and some from his team.^3,4,6,7,8

“RAKT is less invasive than OKT, representing an attractive and promising alternative,” according to Dr Breda.

Cost

Dr Veale, Dr Breda, and Dr Cowan all agreed that RAKT is significantly more expensive than OKT due to the specialized equipment and other factors.

Surgery learning curve

According to Dr Cowan, the learning curve for OKT vs RAKT depends on the surgeon’s background. “Urology residents these days are getting very comfortable with robotic surgery [in general],” he said.

Dr Breda highly recommended hands-on training with a proctor for RAKT. He noted that it takes 35 cases to attain good results in rewarming time, complications, and functional outcomes, based on their team’s study published in European Urology.⁷ Dr Breda said RAKT is a “safe, feasible, and reproducible technique” after the learning curve.

Potential RAKT advantages

According to Dr Breda, RAKT may become the preferred technique in obese recipients and recipients of grafts with multiple blood vessels.

“If you ask me nowadays, I’m probably pushing more and more for robotic-assisted kidney transplantation in the complex population, in the complex kidney grafts. That’s where I think that there is the major advantage,” he said.

Obese patients: In a 2020 study published in World Journal of Urology, Dr Breda and colleagues reported that living donor RAKT in patients with a body mass index (BMI) of 30 kg/m² or higher resulted in similar rates of postoperative complications and delayed graft function as well as similar 1-year kidney function compared with patients with lower BMI.⁹

Multiple vessels: Kidney transplantation using grafts with multiple arteries and veins is technically demanding and may increase risks for complications or subpar graft function. In a 2018 study published in European Urology Focus, Dr Breda and colleagues reported on 21 cases.¹⁰ RAKT using kidneys with multiple vessels was feasible with a low number of postoperative complications and good postoperative kidney function.

Other complex cases: RAKT also appears feasible in select patients with severe stricture of the ureter or aneurysm of the artery requiring autotransplantation of the kidney, according to Dr Breda. His team published results from a small case series in 2022 in European Urology.¹¹

Limitations of RAKT

Prior surgery: Typical OKT is performed using an extraperitoneal approach, whereas typical RAKT uses a transperitoneal approach. Dr Veale suggested that RAKT carries an increased risk of allograft torsion due to the intraperitoneal approach. RAKT is difficult to perform in patients with previous kidney transplantation, Dr Breda observed. Prior abdominal surgery is often not a concern with OKT, but it may be with RAKT.

Keeping the kidney cool: It’s essential to keep the kidney graft cool during transplantation to minimize oxygen demand, prolonged rewarming time, and ischemia-reperfusion injury. A major limitation of RAKT is that the graft is enclosed within the abdominal cavity, which is at normal body temperature, Dr Breda acknowledged. Using ice slush carries a risk of a paralytic ileum. Dr Breda’s group created a patented cooling device to wrap the graft during transplantation. The cold ischemia device provided a constantly low graft temperature during the rewarming time in both OKT and RAKT. The study results were published in European Urology.¹²

Plaques in the iliac artery: Unlike OKT, RAKT does not permit tactile feedback for localizing atherosclerotic plaques in the iliac artery. “If you have to clamp the artery and if you have to perform the arteriotomy in an artery with a lot of plaques, robotically it will be very difficult and potentially very dangerous,” Dr Breda said. In a pilot study, his team used a virtual reality tool to aid real-time atheromatic plaque identification during RAKT. Three-dimensional virtual models of the plaques were constructed from computed tomography scans, then successfully superimposed on the patient’s vessels using the robotic console software. Results of the study were published in European Urology.¹³

In the case of moderate to severe plaques, Dr Breda’s team has tested an orthotopic technique to avoid the iliac artery altogether. After nephrectomy of the native kidney, they connected the renal graft artery to the patient’s splenic artery during RAKT. The study results were published in the World Journal of Urology.¹⁴

In closing the debate, Dr Cowan summarized, “I think in the majority of patients, open kidney transplantation is a really great operation with good outcomes. In a minority of patients, notably those with obesity, robotic-assisted kidney transplantation has a clear advantage. As the robotic approach is further refined, I suspect that its advantages are likely to spread to a broader set of patients.”

Disclosure: Please see the original references for a full list of authors’ disclosures.

References