Surgery for recurrent, chronic or acute diverticulitis is the second most common colon procedure performed in the U.S. Only colorectal cancer surgery is done more often.

The techniques used to treat advanced diverticulitis have improved over time, but as many as 50% of patients still undergo open procedures. Few undergo robotic surgery.

"The majority of the procedures in the U.S. are performed open or laparoscopically," says Dr. Eric Haas, Chief of the Division of Colon & Rectal Surgery at Houston Methodist. "But even with laparoscopic surgery, an abdominal incision is needed to actually remove the specimen and to perform the anastomosis."

It wasn't until the robotic da Vinci Xi platform arrived on the scene in 2018 that a completely minimally invasive robotic procedure for left-sided colon resection would be performed for the first time ever. Dr. Haas and his team were the ones who did it.

Now Houston Methodist is one of the only centers in the world leveraging the approach specifically for diverticulitis.

"We call it the Natural orifice-assisted IntraCorporeal anastomosis with transrectal Extraction of specimen (NICE) procedure," says Dr. Haas. "It's a purely robotic way of approaching diverticulitis surgery and it provides huge benefit to the patient."

Since proving it was feasible three years ago, Dr. Haas and his team have performed more than 300 robotic NICE procedures. All the while, they have shared their knowledge and trained other surgeons, hopeful the procedure will continue to be adopted and benefit patients around the world.

Why eliminating the need for an abdominal incision during colon resection matters

Conventional laparoscopic approaches to colon resection for both colon cancer and diverticulitis have existed for more than 20 years. And the benefits of these approaches versus open surgery — less postoperative pain, shorter hospital stays and quicker recovery times — have always been clear.

"But even with these advancements, the surgeon eventually gets to a point in the procedure where an abdominal incision is needed to extract the damaged segment of colon and prepare for the anastomosis," says Dr. Haas. "And it's this incision that complicates things."

First, it's a site for post-operative infection, especially given what the incision is used for — colon extraction.

"One of the major challenges is that we're literally pulling a dirty, usually infected, specimen through the incision," says Dr. Haas. "This increases the risk of postoperative infection at the incision site substantially. Then, there's what an abdominal incision means more generally for a patient: increased pain, delayed mobilization, increased need for postoperative opioids and the set-up for an incisional hernia to develop in the future."

In particular, reducing postoperative pain — and the resulting need for opioids — is crucial when it comes to colon resection because opioid usage is directly associated with delay of bowel function, nausea, vomiting and the dreaded post-operative ileus. Conventional laparoscopic techniques, as compared to open surgery, have reduced the need for opioids to an extent, but Dr. Haas and his team knew there was still room for improvement.

"After colon surgery, it can take some time for the bowels to 'wake back up,' so to speak, which is a phenomenon called ileus," says Dr. Haas. "Using opioids to treat postoperative pain is the leading cause of postoperative ileus — not to mention the fact that prolonged opioid use is increasingly associated with opioid abuse. Anything that can help us avoid opioid usage altogether significantly benefits the patient."

Conventional laparoscopic techniques left surgeons like Dr. Haas with a question: How to resect the colon and connect the remaining segments without having to make an abdominal incision?

He and his team found the answer in robotic technology.

The NICE procedure: A robotic approach that significantly improves postoperative outcomes

"The foundational concept of the NICE procedure, using the rectum as a natural orifice to complete all steps of the procedure without and incision, isn't what's new," says Dr. Haas. "The way we're approaching it is."

For years, various surgeons have championed minimally invasive natural orifice colectomy techniques, but these were notoriously fraught with technical challenges, requiring a high level of surgical skill and significant time in the operating room. They were so complex that only a handful of surgeons had the expertise needed to perform them. The result: less than 1% of the world's candidate patients got natural orifice resection.

"Fortunately, we have here this amazing culture of always looking towards the future — setting the benchmark for care and adopting cutting-edge tools," says Dr. Haas.

He cites the hospital's investment in robotic surgical systems.

"Having robotic technology in our ORs enables us to perform very complex surgical maneuvers and techniques in an extremely precise, minimally invasive manner — which can tremendously improve patient outcomes," explains Dr. Haas.

It's this technology that Dr. Haas and his team leveraged in order to make minimally invasive colorectal surgery even less invasive.

All of the surgical maneuvers that would be performed within an open abdomen are performed in a stepwise, reproducible and efficient fashion under a pneumoperitoneum. The patient is left with four dime-sized incisions where the ports are placed as the specimen is extracted transrectally.

Dr. Haas and his research team have published and presented the significant benefits of the robotic NICE procedure compared to conventional ones, including:

• Shorter hospital stays
• Less postoperative pain
• Reduced use of opioids
• Earlier return of bowel function
• Reduced postoperative complications
  
  

"Amazingly, the robotic NICE procedure further improves patient outcomes beyond the progress already offered by laparoscopic techniques," adds Dr. Haas. "And it completely eliminates the risk of developing an incision infection or incisional hernia."

He and his team published the NICE procedure and their initial findings in the American Journal of Surgery in 2018.

At the heart of the leap forward is Houston Methodist's unique team-based approach. While robotic systems have made the NICE procedure feasible, it takes an expert team of surgeons working together to pull it off.

"It's not just one surgeon on the robotic console performing the procedure," says Dr. Haas. "There's another surgeon at the bedside and a third surgeon receiving the contaminated colon segment. So it's not just robotic technology that makes the NICE procedure possible. It's a total commitment to approaching patient care with a team-based, forward-thinking mindset."

Refining and standardizing the NICE procedure to promote widespread adoption

After developing this groundbreaking procedure, Dr. Haas and his team initiated a research program to refine and standardize a consistent, reproducible 10-step approach to the NICE procedure.

Three years later, there are now pockets of experts across the world, including in Japan, Brazil and Australia, who have adopted the robotic NICE procedure for colon resection.

In the meantime, Dr. Haas and his team have worked to further improve the NICE procedure so it can safely and successfully treat more complicated cases of diverticulitis, essentially expanding the procedure to any patient requiring surgery. The modified steps and maneuvers for complex diverticulitis were published in Surgical Endoscopy in February 2021.

"The other benefit of this approach is that we can leverage it for colorectal cancer surgery as well," says Dr. Haas. "In fact, it's become the primary way we approach colon resection for either diverticulitis or colon cancer surgery."

Next Steps:

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