INDIANAPOLIS – Robotic-assisted major pancreatic resection is safe, feasible, reliable, and versatile, according to the findings of the largest reported single-center series of such procedures.
That being said, the next and absolutely critical step needs to be comparative effectiveness studies pitting robotic versus laparoscopic or open pancreatic resections, Dr. Herbert J. Zeh III reported at the annual meeting of the American Surgical Association.
He noted that there was a considerable learning curve with the procedure in this single-center series of 250 consecutive robotic-assisted major pancreatic resections. "If we had compared our first 30, 40, or even 60 cases, we would have been comparing an innovative procedure to one that’s been refined continuously since 1937," noted Dr. Zeh of the University of Pittsburgh.
Dr. Herbert J. Zeh III
Discussants praised Dr. Zeh and his coinvestigators as innovators who are taking a rigorously scientific and cautious approach in investigating the applicability of robotic techniques to major pancreatic surgery. But some discussants were concerned that the growing dissemination of robotic surgery is based largely upon what they consider to be marketing hype and competitive pressure.
Dr. Zeh explained that he and his coworkers have undertaken the study of robotic-assisted major pancreatic resections because they believe that a minimally invasive approach will reduce the substantial morbidity traditionally associated with open procedures, and that laparoscopic techniques aren’t the answer in these complex resections, which often require resuturing the pancreas to the GI tract.
"It was our perception as a group of dedicated pancreatic surgeons that we could not utilize the laparoscopic technology to adhere to the standard principles of open surgery that we thought were important for safe performance of pancreatic resections. These include meticulous dissection, safe control of major vascular structures, and precise suturing," he said.
The 250 consecutive robotic-assisted major pancreatic resections in this series included the full range of complex pancreatic operations. The two most common procedures were pancreaticoduodenectomy, also known as the Whipple procedure, in 132 patients and distal pancreatectomy in 83.
Overall 30- and 90-day mortality rates were 0.8% and 2.0%, respectively. All deaths were in pancreaticoduodenectomy patients, with 30- and 90-day mortality rates of 1.5% and 3.8%.
Clinically significant complications occurred in 21% of patients. The most common was intra-abdominal fluid collection requiring drainage via interventional radiology. Morbidity rates were similar to those reported in large series of open and laparoscopic pancreatic resections.
Estimated blood loss in pancreaticoduodenectomy averaged 499 mL in the first one-third of patients who had the robotic procedure; thereafter, the blood loss improved to 401 mL.
Rates of conversion from robotic to open surgery also improved over time, from 18.2% in the first third of the patient series to 3.4% in the latter two-thirds.
Mean operative time was 529 minutes for pancreaticoduodenectomy and 256 minutes for distal pancreatectomy. These times have dropped steadily with experience such that mean operative time in the last 50 pancreaticoduodenectomies was 444 minutes, while in the last 50 distal pancreatectomies it was 222 minutes, which approaches reported times for laparoscopic and open operations, Dr. Zeh noted.
The median length of stay was 10 days for pancreaticoduodenectomy patients and 6 days for those undergoing distal pancreatectomy. As a precautionary measure, surgeons kept patients treated early in the series in the hospital longer than was probably necessary. Length of stay has come down over time, although this trend hasn’t yet reached statistical significance.
The readmission rate was 24% in pancreaticoduodenectomy patients and 28% in distal pancreatectomy patients; 2% of patients required a reoperation.
As experience has grown, the group’s criteria for selecting patients for the robotic approach have loosened considerably. Many recent patients have been obese or superobese.
"Currently the only absolute contraindication is some sort of vascular involvement that would entail resecting a vein and reanastomosing it using a minimally invasive approach. That’s really the only frontier we haven’t crossed," said Dr. Zeh.
The potential advantages of the robotic platform that drew the researchers’ interest include greater range of motion for the robotic needle driver and other tools, compared with what is achievable laparoscopically; enhanced visualization with magnification; computerized smoothing of a surgeon’s tremor; and the ability to see structures in three dimensions, unlike in laparoscopy.
"I think the real advantage is the computer," he added. "Robotic surgery is probably misnamed; it’s really computer-assisted surgery. What this is going to allow us to do is to take the skill sets that we have to the next level. Pilots couldn’t control fighter jets without a computer between them and the plane. In the end, I think the addition of the computer between us and the patient is going to allow us to do things that we haven’t even thought about."