NATURAL ORIFICE TRANSLUMENAL ENDOSCOPIC SURGERY ( NOTES ) A CRITICAL APPRAISAL

hange, is part of surgery but change is never easy to accept. If you look back of surgery, excellence was associated with big incisions: "Big scar, big surgeon.” was the old concept until 1987 when Philippe Mouret, first doing laparoscopic cholecystectomy broke this concept. Surgery with no scars was an impossible reverie. Now natural orifice translumenal endoscopic surgery (NOTES) is being performed, and the philosophy of surgery will be dramatically changed. Translumenal surgery has the potential to break the physical barrier between bodily trauma and surgery, representing an epical evolution in surgery. C


Of Surgery
Bas J Surg, September, 16, 2010   NATURAL ORIFICE TRANSLUMENAL ENDOSCOPIC SURGERY (NOTES) A CRITICAL APPRAISAL Jasim D Saud* & Mushtaq Ch Abu-AlHail @ *General Surgeon FICMS, CABS.@General Surgeon CABS, DGS, Department of Surgery, Basrah General Hospital hange, is part of surgery but change is never easy to accept.If you look back of surgery, excellence was associated with big incisions: "Big scar, big surgeon."was the old concept until 1987 when Philippe Mouret 1 , first doing laparoscopic cholecystectomy broke this concept.Surgery with no scars was an impossible reverie.Now natural orifice translumenal endoscopic surgery (NOTES) is being performed, and the philosophy of surgery will be dramatically changed.Translumenal surgery has the potential to break the physical barrier between bodily trauma and surgery, representing an epical evolution in surgery.

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NOTES is next major paradigm shift in surgery, laparoscopy was major paradigm shift in 1980s and 1990.Antony Kalloo (USA) publication of trans-gastric peritoneoscopy in 2004 2 catapulted NOTES from absurdity to the necessity.After that Recardo Zorron (Brazil) 3 performed hybird transvaginal NOTES cholecystectomy in March 2007, Marc Bessler (USA) 4 had underwent hybrid NOTES transvaginal cholecystectomy with 3 abdominal trocars.In Strasbourg, France in April 2007 totally NOTES transvaginal cholecystectomy with Verese needle for insuflations' was done by Marescaux 5 and in June 2007 Lee Swanstrom (USA) 4 was doing the first hybrid NOTES transgastric cholecystectomy with 2 abdominal ports used for laparoscopic closure of stomach.In a brief time period, NOTES has been shown to be feasible in numerous laboratory animal studies and also in limited human studies [6][7][8] .As the data accumulate and instrumentation improves, NOTES may play a role in the future of abdominal surgery.
The Procedure: The core concept NOTES consist of introduction of a flexible endoscope through one of the body's natural orifices, perforation of a viscous, and performance of abdominal surgery using endoscopic visualization.The endoscope may be inserted through the mouth, anus, urethra, or vagina with puncture of the stomach (the esophagus for mediastinal exploration), rectum, urinary bladder, or vagina, respectively.For transgastric surgery, a standard gastroscope is passed through the mouth into the stomach.A small anterior gastrotomy is made, typically with an endoscopic needle knife.A wire is passed through the site into the abdominal cavity, and then the tract is enlarged with an endoscopic dilating balloon to accommodate the endoscope.Transcolonic and transvesical operations use similar methods for entering the peritoneal cavity.Once the endoscope in advanced into the abdominal cavity, a pneumoperitoneum is generated using endoscopic insufflations'.The scope is maneuvered to view the organ of interest.Standard endoscopic instruments, such as biopsy forceps and polypectomy snares, are then passed through the working channels and used for tissue manipulation.When the operation is completed, the endoscope is returned to the lumen of this viscous and the viscerotomy is closed.

Advantages
In addition to no scar, no hernia, no wound infection, the immunologic impact of NOTES may be favorable for the patient.A recent laboratory study from Case Western Reserve University showed lower levels of tumor necrosis factor-α (TNF-α) after NOTES peritoneoscopy compared to laparoscopic abdominal exploration and laparotomy 9 .NOTES may lead to less impairment of the peritoneal immune system and possibly even improved oncologic and infectious outcomes.Natural orifice surgery may decrease the degree of abdominal adhesion formation.Much like laparoscopy, the minimal access nature of NOTES might diminish the stimuli for adhesions and, subsequently, reduce the incidence of postoperative bowel obstruction or simplify future abdominal operations.Another possible derivative of NOTES is single port laparoscopy and other hybrid procedure.
As an example, a cholecystectomy might be performed through a single 10-mm umbilical port.NOTES can likely be performed without the need for general anesthesia.As no skin incision is made, the requirement for analgesia might be satisfied with conscious sedation.Therefore, NOTES could be performed in the intensive care unit or endoscopy suite, rather than a standard operating room.The NOTES team and its equipment are portable.A single endoscopy tower house is all of the necessary equipment.Furthermore, most NOTES procedures are performed without sterile instruments, but with scopes subjected to high-level disinfection.This makes NOTES amenable to austere environments, such as battlefields and developing countries, where sterilization equipment is not available.
Finally, the esthetic benefits of NOTES.The public at large has become captivated with the concept of "no-scar" abdominal operations.This is feasible with pure NOTES cases, although esthetics should not be the driving force behind NOTES.

Drawbacks
Creating a hole, intentionally in one of the viscera repudiates decades of surgical dogma.The patient might be susceptible to infectious and immunologic consequences that are not present in laparoscopy and conventional surgery.The inherent flexibility of the endoscope impedes achieving a stable operating field.In-line endoscopic tools have a restricted range of motion and limited degrees of freedom.In addition, in-line instrumentation and optics do not allow triangulation of the visual field and instruments, a concept found to be critical in laparoscopy.Besides the prototypes used in the laboratory, most currently available equipment is inadequate for performing retraction, meticulous dissection, and bimanual manipulations.
As a purposeful viscerotomy is made in NOTES, its secure closure is imperative to ensure the safety of the operation.Initial laboratory work managed the viscerotomy without closure or by occlusion using a percutaneous endoscopic gastrostomy (PEG)-type gastrostomy tube 9 .Both methods were fraught with high rates of intraabdominal contamination in the porcine model.There is no reliable, simple, and safe method for achieving full-thickness, water-tight closure of the viscerotomy thus; more reliable methods that achieve full-thickness closure of the viscerotomy are currently being investigated.

Achievements so far
The seminal publication by Kalloo and colleagues led to the organization of the Apollo group.Shortly after the publication of transgastric peritoneoscopy, the Apollo group published reports on transgastric tubal ligation 10 , gastrojejunostomy 11 , and splenectomy 12 in a porcine model.Recently, members of the Apollo Group collaborated in the performance of per oral transgastric ventral hernia repairs in a porcine model.These publications were significant in that complex operations were shown to be feasible using NOTES techniques and the animals survived without undue complications.Many teams followed the Apollo feasibility Group's lead and performed animal studies.Transgastric appendectomy 13 , cholecystectomy, 14 and oopherectomy 15 were performed.The Transcolonic 14 approach has been used to perform cholecystectomy, and the transvaginal approach has been used in laboratory animals to perform nephrectomy 16 .Combined transrectal and transgastric approaches allow performance of complex small bowel resections with intracorporeal formation of anastomoses 17 .Reliable closure of the viscerotomy is the critical step in avoiding intra-abdominal infection.
Leaving the viscerotomy open and PEG tube occlusion of the gastrotomy were shown to be inadequate in the porcine model.Endoscopic clips, as might be used in a bleeding vessel, have also been used with some success 18 .However, clips only provide mucosal approximation, and a full thickness closure comports with proven surgical principles.Numerous devices have been used to attempt full thickness closure.One such instrument is the NDO Plicator.Closure of full-thickness gastrotomies has been shown to be reliable with the NDO Plicator 19 .Survival studies in laboratory animals have shown minimal rates of intraabdominal infections after transgastric peritoneoscopy and closure with the NDO Plicator.Another group has developed a method of gastrotomy closure using a commercially available overtube and suturing device 20 .A method of translumenal access has been developed by the Penn State group that might obviate the need for full thickness closure, deemed the self-approximating translumenal access technique (STAT) 21 .In animal studies, the Ohio State group has closed gastrotomies with a bioabsorbable plug, such as might be employed in inguinal hernia repair 22 As in laparoscopy, the intra-abdominal pressure requires continuous monitoring during NOTES.Unchecked insufflations' might lead to abdominal compartment syndrome.A recent study has shown that pressure transducers fitted to the end of a gastroscope or passed through a working channel detect intraabdominal pressure with a high degree of correlation with actual intraabdominal pressure 23 .Adequate retraction is imperative to safely perform complex abdominal operations, such as cholecystectomy.The group from the University of Texas-Southwestern has developed a clever method using intraabdominal magnets to provide retraction during NOTES procedures 24 .

The Absolute Pre-requisites
The NOTES surgeon should be expert in flexible endoscopy, abdominal anatomy, and surgical technique.He or she should be facile in managing the preand postoperative care of the patients and, in particular, should be capable of handling complications from the procedure.Many would argue that NOTES surgeons should be able to perform an operation laparoscopically and conventionally, as conversion to one of these modalities is a possibility in any NOTES procedure.Trainees should dedicate a substantial amount of time to laboratory endeavors, as this is where skills can be safely honed before clinical application.The Future of NOTES While it is improbable that we are on the brink of widespread pure clinical NOTES, there are many potential applications of NOTES that will likely manifest.Given the portability of NOTES equipment and the requirement for only conscious sedation, natural orifice surgery is ideally suited for the intensive care unit.There are two potential scenarios that have been described that are amenable to ICU NOTES: diaphragm pacing and peritoneoscopic examination for ischemic bowel 25,26 .The minimal equipment requirements and the need for high-level disinfection, rather than sterilization, make NOTES appropriate for developing regions of the world.The transportable nature of NOTES might be applicable for battlefield abdominal exploration.NOTES do not signal the demise of traditional gastrointestinal surgery or laparoscopy.It is plainly evident that extraordinary advances are required before NOTES can be considered for widespread application.Rather than succumbing to the fervor for NOTES, we must take a circumspect view of NOTES.Diligent laboratory research is imperative, followed by cogent clinical trials.Above all, regard for patient safety must prevail.Only those with vast laboratory experience with NOTES should contemplate clinical NOTES procedures.Initially, only patients enrolled in clinical trials should undergo NOTES.Finally, the burden is on NOTES investigators to perform due diligence on this nascent field and ensure that we are doing the right thing for our patients.