In a sign that the future of minimally-invasive surgery is surely upon us, Dr. Ralph Clayman, Dr. Geoffrey Box and colleagues at UC Irvine report in this month’s Journal of Endourology that they have successfully performed a robot-assisted NOTES nephrectomy on a porcine model.

NOTES, short for natural orifice transluminal endoscopic surgery, is a catch-all term for surgeries performed using endoscopes that reach the peritoneal cavity via incisions in the stomach, vagina, colon, or bladder. It’s about as non-invasive as surgery gets, with many cases requiring no abdominal incisions at all. Although there have already been numerous reports describing NOTES procedures, this is the first we know of that successfully integrates the da Vinci robot.

So why is the addition of the robot such an important development? Well, NOTES cases aren’t easy! The working space is very limited, and the awkward set-up makes it difficult to position instruments and achieve traction. Robotic assistance would thus be extremely helpful and could accelerate the development and adoption of NOTES in general.

The case documented in this procedure was considered a success and was described as follows:

• Two 12-mm ports were placed in the vagina and colon, while a 12-mm trocar was placed in the midline for the robotic camera and insufflation.
• The robotic arms provided better traction than purely endoscopic instrumentation.
• A human vagina could probably accommodate two ports, especially if 5-mm ones are used, which would obviate the need for one in the colon.
• The intact kidney was removed in an entrapment sack via the vagina.
• Access site closure was not attempted.
• Operative time was 150 minutes, with <50 mL blood loss and no complications.

Even though there was a successful outcome, the article points out a number of obstacles that still must be addressed. A key issue is port spacing: although robotic ports should be at least 3 inches apart to prevent arm collision, this is impossible when both are in the vagina, or when one is in the vagina and the other in the colon. In this case, the authors note that although collision was not a dealbreaker, it was very frequent and annoying.

Furthermore, according to Dr. Clayman, such procedures continue for the foreseeable future to be possible only in females. He noted, “I believe that going through the colon, bladder, or stomach to remove an organ as large as the kidney will be problematic, to say the least, unless a clever way of entrapment and morcellation becomes feasible.”

It’s reasonable to expect, however, that many of these issues will be resolved in the coming months and years, and that successful robot-NOTES integration will cause big waves in surgery. We’ll be keeping a close eye on developments in this area.