Natural orifice transluminal endoscopic surgery : Past , present and future

Natural orifice transluminal endoscopic surgery proceeding to clinical (NOTES). Eliminate natural (NOTES) first gained notoriety with the initial orifice transluminal endoscopic surgery. laboratory report of transgastric peritoneoscopy in Since then the medical community and the SOME ADVANTAGES general public has been captivated with the idea of “no-scar” abdominal surgery. In animal models, There are many potential advantages of NOTES over translumenal organ resections have been shown to conventional surgery. Much like laparoscopy has be feasible and an unpublished clinical case series demonstrated less physiologic impact than of transgastric appendectomies has been discussed laparotomy, NOTES may cause less physiologic across the world. However, as data accumulate we insult than either laparoscopy or laparotomy. are learning that NOTES techniques requir Laboratory studies are underway investigating substantial refinement before achieving clinical cytokine levels with NOTES in comparison to conventional operations. Furthermore, natural orifice surgery may negate the possibility of wound complications and reduce the formation of intraabdominal adhesions. Natural orifice transluminal endoscopic surgery (NOTES) involves accessing the abdominal cavity via Given the portability of NOTES equipment, natural one of the bodies’ natural orifices (mouth, anus, vagina orifice surgery is suited for an intensive care unit. or urethra). A flexible endoscope is advanced into the Moving the equipment to the patient, rather than peritoneal cavity after puncturing one of the viscera vice versa, might reduce the resource requirements 2004.

Natural orifice transluminal endoscopic surgery proceeding to clinical (NOTES).Eliminate natural (NOTES) first gained notoriety with the initial orifice transluminal endoscopic surgery.laboratory report of transgastric peritoneoscopy in Since then the medical community and the

SOME ADVANTAGES
general public has been captivated with the idea of "no-scar" abdominal surgery.In animal models, There are many potential advantages of NOTES over translumenal organ resections have been shown to conventional surgery.Much like laparoscopy has be feasible [2][3][4][5][6][7] and an unpublished clinical case series demonstrated less physiologic impact than of transgastric appendectomies has been discussed laparotomy, NOTES may cause less physiologic across the world.However, as data accumulate we insult than either laparoscopy or laparotomy.
are learning that NOTES techniques require Laboratory studies are under way investigating substantial refinement before achieving clinical cytokine levels with NOTES in comparison to conventional operations.Furthermore, natural orifice surgery may negate the possibility of wound complications and reduce the formation of intraabdominal adhesions.Natural orifice transluminal endoscopic surgery (NOTES) involves accessing the abdominal cavity via Given the portability of NOTES equipment, natural one of the bodies' natural orifices (mouth, anus, vagina orifice surgery is suited for an intensive care unit.or urethra).A flexible endoscope is advanced into the Moving the equipment to the patient, rather than peritoneal cavity after puncturing one of the viscera vice versa, might reduce the resource requirements 2004. [1]plicability.
(stomach, colon, vagina or bladder).Endoscopic insufflation creates a pneumoperitoneum and the appropriate working space.Conventional endoscopic instruments are advanced through the working channels of the endoscope in order to perform the operation.
That simple action of purposely puncturing one of the viscera has raised many questions: What are the infectious implications?How can reliable closure be achieved?Is it practical to make a viscerotomy in the era of minimal access laparoscopic surgery?These questions all require cogent answers before and potential complications of transporting a patient to the operating room.Moreover, NOTES could be performed under conscious sedation, rather than general anesthesia, again favoring intensive care unit (ICU)-based procedures.
Lastly are the cosmetic benefits of NOTES.While NOTES would offer abdominal operations without skin incision, this fact should not be the driving force behind NOTES.The public at large may be enchanted with no-scar surgery, but physicians and surgeons should make rational decisions based on sound data.

NUMEROUS DRAWBACKS
Besides the fact that intentionally puncturing one of the viscera contravenes surgical dogma, there are many shortcomings of NOTES in its current state.It has become plainly obvious that current instrumentation is inadequate to perform NOTES.
Making the viscerotomy and accessing the abdomen is feasible using standard endoscopic equipment, but beyond those steps, technical advances are imperative for the success of NOTES.
mucosa, which contravenes surgical dogma.Therefore, technical advances are necessary to develop a method of reliable full-thickness, watertight visceral closure.

THE WAY FORWARD
Members of the American Society for Gastrointestinal Endoscopy and the Society of American Gastrointestinal and Endoscopic Surgeons joined to form a new group, Natural Orifice Surgery Consortium for Advancement and Research (NOSCAR).The purpose A stable operating platform is necessary to safely of forming NOSCAR was to regulate the progress conduct precise abdominal operations.The flexibility toward clinical NOTES and to ensure the safety of of the endoscope provides the ability to maneuver future procedures.to the organ of interest.However, the flexibility also precludes stabilization of the tip of the scope.A NOSCAR leadership.Eliminate recently published its stiffening overtube might solve this problem.
recommendations for the progression of NOTES in the "White Paper ". [8] A clarion call for rigorous One of the basic tenets of laparoscopy is triangulation laboratory research was sounded.Investigating the of optics and instrumentation.The current version immunologic and infectious implications of NOTES of end-viewing endoscopes precludes such was emphasized.Moreover, NOSCAR recommended triangulation in natural orifice surgery.The working that all teams investigating NOTES cases be conducted channels are in line with the optical view, limiting under the guidance of local Institutional Review range of motion of instruments and obscuring the Boards and entered into a centralized database for view of the operative field.
tracking of outcomes.
The published NOTES feasibility studies have used Perhaps most importantly was the exhortation for standard endoscopic instrumentation to perform cooperation between gastroenterologists and abdominal operations.In clinical practice biopsy surgeons in advancing NOTES.NOSCAR recommended forceps and snares may be adequate for simple that all teams investigating NOTES be comprised of manipulations, but complex surgery, such as that on at least one surgeon and one gastroenterologist the biliary tree, demands improved instruments.
working in cooperation to advance the fledgling field Again, a triangulating endoscope would permit of NOTES.concomitant retraction and dissection of tissue.Innovative instruments might allow greater degrees of freedom than are currently available with conventional endoscopic tools.
Foremost is the requirement for a reliable method for closure of the viscerotomy.In a porcine model, some groups have advocated no closure of a gastrotomy.Others have successfully employed endoscopic clips for closure.Neither of these comports with the surgical principle of full thickness closure of a viscerotomy.Endoscopic clips and some endoscopic sewing machines only approximate the QUALIFICATIONS Should clinical NOTES come to fruition, the issue of qualifications and credentialing for performing translumenal surgery arises.Should gastroenterologists or surgeons be the practitioners of NOTES?
In all likelihood, only a small fraction of highly trained gastroenterologists and surgeons will become NOTES surgeons.Performing NOTES is contingent upon demonstrating expertise in flexible endoscopy, abdominal anatomy, surgical principles and  The portability of NOTES equipment is ideal for performing transgastric surgery in the intensive care gastroenterologists and surgeons with an interest in unit.A large percentage of ICU patients rely on acquiring the necessary skills and knowledge base temporary respiratory support, but weaning from the to perform transgastric surgery.
ventilator might be facilitated by diaphragm pacing.Transgastric placement of diaphragm pacing leads

BRIDGE PROCEDURES
has several potential benefits over laparoscopic placement. [9]The resource requirements and hazards In addition to sound laboratory research, a stepwise of transportation would be negated and the clinical approach to clinical NOTES allows safe procedure could be performed under sedation at the progress.Transgastric peritoneoscopy under bedside.laparoscopic guidance serves as a bridge to NOTES, assessing the practicality and safety of transgastric surgery in humans.These bridge procedures might Another potential ICU application is transgastric be performed in patients requiring laparoscopic abdominal exploration for compromised bowel in operations requiring a gastrotomy.For example, suspected cases of mesenteric ischemia.Detecting necrosis of the entire small bowel would obviate a posterior gastric wall GI stromal tumors might be resected through an anterior gastrotomy.After making trip to the operating room for a nontherapeutic the gastrotomy the endoscope could be passed into laparotomy.Findings of limited ischemia or necrosis the abdominal cavity and peritoneoscopy could be would serve to select those patients who might performed with laparoscopic supervision.benefit from a laparotomy.
Bridge procedures permit investigation of some of Managing complications of percutaneous endoscopic the critical issues of NOTES: Infectious implications gastrostomy tubes could and scope positioning.In some reports using a endoscopically in the ICU.We have recently porcine model there was a high rate of performed a NOTES transgastric "rescue" of a intraabdominal abscess formation after transgastric dislodged PEG in the ICU under conscious be performed peritoneoscopy.Whether this was a function of the porcine model or the result of transgastric endoscopy could be answered by clinical bridge procedures.Moreover, the maneuvers necessary to visualize the various abdominal organs could be assessed, thereby providing insight into the placement of the viscerotomy and the necessary technical refinements.

FUTURE APPLICATIONS
The initial applications of NOTES will likely transcend sedation. [10]An elderly neurologically-compromised patient removed his PEG 3 days after initial placement.A contrast study through the previous PEG site revealed free intraperitoneal dissemination of contrast.In order to spare the patient a laparotomy a flexible endoscope was advanced through the previous gastrotomy into the peritoneal cavity.A percutaneously placed wire was snared with the endoscope and the PEG was restored in its previous position.The patient recovered uneventfully without evidence of intraabdominal infection.

CONCLUSIONS
We may be a long way from routine clinical applications of NOTES, but we are making steady progress.Circumspect laboratory investigation is critical to understanding the physiologic impact of translumenal surgery.Moreover, all clinical NOTES should be performed under the aegis of a cogent clinical trial.Finally, a spate of new instrumentation is vital for performing safe NOTES.
There may be a time when transgastric cholecystectomy is routine, but that time is not now.Patient safety, not the advancement of NOTES, is paramount.Presently, we should perform diligent laboratory research and possibly some limited clinical trials, awaiting the data confirming our suspicion that NOTES is the way of the future.
et al.: Natural orifice transluminal endoscopic surgery Pearl, et al.: Natural orifice transluminal endoscopic surgery