Inside the operating room—balancing the risks and benefts of new surgical procedures

Natural orifice transluminal endoscopic surgery: Too much too soon?

By Christopher Thompson, MD, MHES

Although the endoscope has changed very little since the first fiberscope was developed 50 years ago, the accessories and other instruments used in conjunction with the endoscope have changed remarkably. These include clips for hemostasis, ultrasonographic technology, and instruments for tissue dissection.

These advances in endoscopy, combined with advances in laparoscopic surgery, have led to the convergence of these two fields, culminating in the new field of natural orifice transluminal endoscopic surgery (NOTES). In NOTES, the surgeon enters a natural orifice and punctures through a viscus to perform surgery, removes the endoscope, and closes the area without leaving a scar.

HISTORY OF NOTES AT A GLANCE

NOTES was patented as a concept in 1992. Its first application was as an exploratory procedure in the pig in 2004.³⁸ Soon thereafter, therapeutic NOTES procedures in animals were reported, including tubal ligation, organ resection, cholecystectomy, and splenectomy.

Particularly notable in the development of NOTES is the extremely short interval between early animal experiments (2004) and the first human procedures, which took place as early as 2005 when surgeons in India used the technique to perform a human appendectomy. Since then, more than 300 NOTES procedures have been performed in humans throughout the United States, Europe, Latin America, and Asia, for applications ranging from percutaneous endoscopic gastrostomy rescue to transvaginal cholecystectomy.

This rapid adoption of NOTES in humans is concerning, as it raises clear questions about whether there has been time for adequate oversight and safety assessment. For instance, at a surgical conference in April 2008, questions and debate swirled around whether a large Brazilian registry of more than 200 NOTES cases did or did not include two deaths. Other ethical issues raised by NOTES are discussed further below.

DRIVING FORCES BEHIND NOTES

The medical rationale

Abdominal wounds can cause pain, are unaesthetic, and are prone to wound infections, ruptures, and hernias. They sometimes cause adhesions or may lead to abdominal wall syndromes with scar neuromas that cause pain later. They also require general anesthesia. Beyond these shortcomings of incision-based procedures, NOTES offers potential reductions in length of stay and therefore in cost. Moreover, certain patient populations may specifically stand to benefit from NOTES, such as obese patients, those with abdominal mesh in place, and those undergoing palliative procedures. This is the essence of the medical rationale for NOTES, which is somewhat thin.

Professional organizations and courses

In July 2005, leaders from the American Society of Gastrointestinal Endoscopy and the Society of American Gastrointestinal and Endoscopic Surgeons convened a working group to support and plan for the responsible development of NOTES.³⁹ The group formed the Natural Orifice Surgery Consortium for Assessment and Research (NOSCAR), an organization that has since sponsored several conferences on NOTES and procured millions of dollars in grants for NOTES research in animals. (In the interest of full disclosure, I am one of the founding members of NOSCAR.)

Additionally, leading institutions in this field have held numerous hands-on courses on NOTES throughout the United States, Europe, Latin America, and Asia. These courses, including those held by my laboratory at Harvard University, are designed to teach colleagues at other institutions how to set up an appropriate animal laboratory and to promote and encourage proper research in NOTES. There have been unintended consequences, however, as we have learned that some course attendees have returned to their home countries and immediately started using the techniques in humans.

New technology

At the July 2005 working group meeting that launched NOSCAR, we determined that several technological advances were needed before NOTES could be safely applied to humans. These included development of multitasking platforms, better devices for tissue apposition and fixation, better imaging and spatial orientation, and improved means of retraction.³⁹ Industry responded with novel devices and end effectors such as guide tubes, direct drive systems, endoscopic suturing devices, magnetic retraction, devices for closing luminal defects, flexible staplers, and computerized robotics.

Other driving forces

Additional forces have undoubtedly contributed to the rapid development of NOTES:

• The slowdown in innovation in general surgery in recent years has left a vacuum to be filled.
• An abundance of venture capital has been available to rush into that vacuum.
• Perceived patient demand (owing to cosmetic advantages) has been a driver, especially in cities such as Rio de Janeiro, Milan, and New York.
• The fear of being left behind is a factor that cannot be underestimated. Surgeons who failed to convert to laparoscopic techniques from open techniques in the early 1990s for procedures such as cholecystectomy, fundoplication, and splenectomy were losing their patient bases. Many surgeons fear a similar phenomenon today if they do not adopt NOTES into their practices.

ETHICAL ISSUES RAISED BY NOTES

As NOTES moves toward further evaluation in humans, several ethical questions need to be grappled with:

• Must there be a significant potential for improvement in care before an innovation advances to human research?
• Is the cosmetic benefit of NOTES sufficient, considering the substantially increased risk? For instance, laparoscopic cholecystectomy is well established, whereas NOTES cholecystectomy carries an increased risk of bile duct injuries and other injuries. Is NOTES worth the risk?
• What about the corporate agenda behind new technologies and its associated influence on the media?
• Are hospital IRBs adequate to the task of evaluating and monitoring these questions, and will they be independent of the impact of hospitals’ larger agendas?

Finally, the problem of premature adoption of this technology is particularly concerning. I heard a surgeon explain at a course that he performed NOTES on a few pigs at a previous course and then returned home to Peru and immediately started performing it on patients at his ambulatory surgery center. There is also the temptation for well-respected surgeons to go to other countries to practice their NOTES skills before returning to the United States, in hopes that their experience will help them attain IRB approval. Practices like these raise questions about what ethical responsibilities lie with those of us who have pioneered the technology and are trying to develop and disseminate it responsibly. We can try to vigilantly watch course attendees from certain countries, but there is little we can do in the absence of regulation and enforcement in those countries. These are difficult ethical challenges.