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Implementation of single-port surgery and notes in clinical practice

van den Boezem, P.B.

2013

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citation for published version (APA)van den Boezem, P. B. (2013). Implementation of single-port surgery and notes in clinical practice.

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1CHAPTERGEnERAl inTRoduCTion

And ouTlinE of THis THEsis

Peter van den Boezem

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1bACkGROUNDThe introduction of laparoscopic techniques in the early 1990s revolutionized the field of

surgery. Many traditionally open procedures were replaced by minimally invasive techniques.

Laparoscopic surgery provides benefits to patients with regard to recovery, hospital stay,

postoperative morbidity, return to normal activities and cosmetic results1-7. Currently, the

laparoscopic approach has become the standard of care for most abdominal procedures,

including the treatment for gallstones and benign and malignant colonic diseases.

INTRODUCTION OF NOTES AND SINGLE-PORT SURGERYIn recent years, rapidly emerging technologies and improved techniques have blurred the

boundaries between gastro intestinal (GI) surgery and therapeutic GI endoscopy and brought

minimally invasive endoscopic surgery closer to a once-elusive goal: incisionless surgery.

NOTES (Natural Orifice Transluminal Endoscopic Surgery) comprises a number of techniques,

in which a natural orifice is used to gain access to the peritoneal cavity instead of initiating

an operation with an incision through the skin. Natural orifices that can be used for a NOTES

procedure are the vagina, the urine bladder, the stomach, or the rectum8-11. NOTES challenges

the basic paradigm of surgery; the idea that it should be avoided to enter the lumen of an organ

to gain access into the patient’s abdominal cavity. Surgeons have always avoided to cross these

borders unless they were operating on that specific organ.

Advantages

In theory NOTES can have enormous advantages for the patient. The most obvious, but

perhaps least important benefit for patients is the absence of visible scars, resulting in an

optimal cosmetic result. The absence of abdominal scars also means no wound infections and

no long-term wound related complications such as hernias.

Other advantages of NOTES procedures when compared to conventional laparoscopy could be

related to the reduced invasiveness and the amount of surgical trauma caused by the access route.

The reduced amount of trauma could result in a faster postoperative recovery, reduced

postoperative pain and therefore a lower requirement of anaesthetic drugs and possibly a

shorter hospital stay. However, it will be difficult to prove that NOTES is less painful than current

minor laparoscopic procedures such as an appendectomy. Larger and more complex procedures

such as colorectal surgery are possibly better indicated to compare the postoperative pain

profiles. However, reports describing colorectal NOTES are still scarce and it could therefore

take a while before comparative studies will be carried out. Nonetheless, Marks et al. reported

in 2007 a PEG rescue procedure and entered the peritoneal cavity under conscious sedation in

a monitored care setting without the use of general anaesthesia12.

Current Challenges

By performing transgastric peritoneoscopies in porcine models, Kalloo et al. were regarded

as the first to describe a NOTES procedure in 2004 and attracted tremendous interest from

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surgeons and gastroenterologists around the world13. NOTES could be the logical next step in

performing laparoscopic surgery. The challenges posed by NOTES surgery where thoroughly

addressed in a “white paper” published in 200614 (Table 1). A working group called NOSCAR

(Natural Orifice Surgery Consortium for Assessment and Research) wrote this paper. Although

research and publications have shown an exponential growth since 2005, most of these

challenges remain a threshold to the widespread introduction of NOTES in 2012.

Table 1. Potential barriers to clinical practice

Access to peritoneal cavity

Gastric (intestinal) closure

Prevention of infection

Development of suturing device

Spatial orientation

Development of a multitasking platform

Control of intraperitoneal hemorrhage

Compression syndromes

Training other providers

Management of iatrogenic intraperitoneal complications

Physiologic untoward events

Adapted from “white paper” 14

The peritoneal cavity can be accessed through mouth, vagina, rectum and urinebladder. Safe

access and safe closure of these entry points is crucial for implementation in day-to-day clinical

practice such as cholecystectomy or appendectomy. Current laparoscopy is safe and access

related morbidity is very low15, thus even a leakage rate of 1 or 2% after a NOTES procedure is not

acceptable. Yet the stomach and the rectum, may be prone to complications from infections,

should an incision fail to close properly. This is the main challenge for all NOTES procedures and

in particular those who use the oral route16.

The vaginal route is probably the easiest incision to close, as it can be done under direct

vision, without the use of any special instruments. Moreover, transvaginal access is routine for

gynaecologic surgeons and they have developed great experience with hydrolaparoscopy17.

Nonetheless, many GI surgeons question the safety of the transvaginal route. Several

publications have emphasized the possible impact on fertility and change in sexual function18-20.

Younger nulliparous women express the greatest concern with any change in sexual functioning.

On the other hand these patients are most concerned with cosmesis and are therefore ideally

suited for NOTES. To our knowledge, there is no evidence in literature that supports a negative

impact on fertility at this moment.

Prevention of infection is another issue that has to be addressed. It is difficult to create a

sterile environment and access through another organ may increase the risk of intraperitoneal

infection and contamination. However, during regular laparoscopic or open bowel surgery,

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1minor contamination is also common and well tolerated. In a study on female pigs, the

intraperitoneal bacterial load and contamination during transgastric and transvaginal surgery

was investigated21. The transvaginal approach proved to be safer and produced less intra-

abdominal contamination and sepsis, compared to the transgastric approach.

Besides a fear for an increase in complications caused by the access route, there is also a fear for an

increase of complications due to an increased complexity. The reduced freedom of motion during

NOTES procedures makes it more complex. The loss of spatial orientation is probably a bigger

problem for surgeons than for gastroenterologists. Gastroenterologists are accustomed to working

in-line with the camera because all instruments pass through working channels on the endoscope

in contrast to laparoscopic surgeons, who work with different access sites (if not performing a

Single-Port procedure). Loss of triangulation is also an issue that has to be encountered. If the

principles learned in advanced laparoscopic surgery are applicable to NOTES, then orientation, as

well as triangulation, will be fundamental requirements for any NOTES procedure14. Development of

multitasking platforms could be helpful to overcome these problems.

A considerable amount of work in this thesis is devoted to new techniques for cholecystectomies.

A pivotal step during a laparoscopic cholecystectomy is the visualization of “critical view of safety”

(CVS) according to the safety rules of Strasberg 22,23. Adherence to these rules minimises the risk

of bile duct injuries. Loss of spatial orientation and triangulation makes it more difficult to reach

CVS. NOTES can only be competitive with current surgical techniques if differences in speed

and facility are minimal with (at least) equal safety of the procedures. As a result of loss of spatial

orientation and triangulation progress during more complex procedures is slow. We regard a

cholecystectomy already as a complex procedure because of the dissection in a small area and the

subsequent need to obtain CVS. An increase in procedure related complications is not acceptable.

Attempting to replace the most frequently performed and successful laparoscopic procedures is

extremely difficult. Regular laparoscopic procedures as cholecystectomy and appendectomy are

associated with a low risk of morbidity and a very low risk of mortality combined with a high level

of patient satisfaction, so there is only little room left for improvement24.

ACCESS ROUTEAll these challenges have divided research and development of NOTES. Gastroenterologists

focus mostly on the transgastric and transesophageal route, endoscopic surgeons have

explored the transvaginal route en more recently the transrectal route.

Independent of the route, safe introduction in the abdomen is essential. Pure NOTES

procedures are therefore rare at this moment and most procedures are currently performed

as a hybrid technique. During a hybrid NOTES procedure an extra 5 mm trocar is placed at

the umbilicus to provide a safe entry through vagina or stomach. Currently, the transvaginal

approach is the most popular. It provides a safe entry, a simple closure and the opportunity to

utilize regular laparoscopic instruments21.

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Transvaginal

The anatomical basis for the transvaginal approach is the wide posterior fundus of the vagina

formed as a result of the anteversion position of the uterus25. As it is not adherent to the anterior

face of the rectum and has no interposed organ or anatomical structure, it allows direct entry to

the peritoneum. The absence of pain nerves in the fornix posterior is a great benefit and makes

it even possible to perform a hydrolaparoscopy under local anesthesia26. Contra indications for

transvaginal NOTES include radiotherapy and major surgery in the pelvis. As a result of an infection

or a history of endometriosis, the Douglas pouch can shrink and thus making it difficult to insert

a trocar without damaging a bowel. Most reported concerns with the transvaginal route focus

on fear for dyspareunia, infertility and withdrawal of sexual intercourse for a number of weeks27.

Transrectal

Dutch surgeons have a wide experience with transanal endoscopic microsurgery (TEM ) for transanal

surgery28,29. TEM is used for the excision of both benign and malignant rectal tumours, but is relatively

expensive and can be a challenging technique. Combination of Single-Port techniques and NOTES

has increased the possibilities for TEM procedures and colorectal surgery in general. Transrectal

specimen extraction after a laparoscopic sigmoid resection is an example of natural orifice specimen

extraction30. Currently, NOTES techniques are applied to rectal surgery. Visualization of the pelvic

anatomy is excellent compared to open and laparoscopic rectal procedures.

Transgastric

Endoscopic gastroenterologists have developed significant experience with transgastric

drainage of pancreatic pseudocysts and pancreatic necrosis, most of which are found in

a retrogastric position31. It was only a small step to relocate the gastrostomy to the anterior

gastric wall and advance the endoscope into the peritoneal cavity13. Several devices have been

developed and tested in animal models and are currently tested in trials with humans10,12,32-37. The

safety of performing a transgastric staging peritoneoscopy prior to a pancreaticoduodenectomy

has also been extensively demonstrated38.

Transesophageal access using a submucosal tunnel is another well-studied NOTES approach39.

Lymph node biopsy following mediastinoscopy has been carried out in animal experiments and

could be helpful in lung cancer staging in the future40. Promising results have been reported for

the peroral endoscopic myotomy procedure (POEM) in the treatment of achalasia41.

The gallbladder is one of the major targets of NOTES reseachers42. It can be challenged whether

the transgastric access is ideal for approaching the gallbladder. From a geometric point of view

the transvaginal, or theoretical transcolonic, access provides a straight route to the upper

abdomen diminishing the need for complicated and expensive flexible devices.

The transgastric route is not subject to discussion of this thesis and the techniques are therefore

not discussed in detail.

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1

Gastroenterology & Hepatology Volume 8, Issue 6 June 2012 387

N a t u r a l O r I f I c e t r a N s l u m e N a l e N d O s c O p I c s u r G e r y

undergo the new procedures, although they were interested in performing them.40 More recent surveys from Switzer-land, Australia, and the United States have revealed that women may be more interested in undergoing transvaginal gynecologic operations than general surgical operations.41,42 Overwhelming patient requests for new procedures—as seen with laparoscopic cholecystectomy in the early 1990s—has not been the driving force for further develop-ment of NOTES technology.

What Procedures Can Endoscopists Start Performing Immediately with Minimal Training? One procedure that endoscopists can start performing immediately is PEG rescue. Using a NOTES technique, Marks and colleagues treated a patient with a dislodged PEG tube that had been recently placed.7 A Gastrografin study revealed that the tube was in the peritoneal cavity. The technique involved passing the endoscope through the existing gastrostomy site, inspecting and suctioning the peritoneal cavity, replacing a wire through the tube via the peritoneal cavity back in the gastric lumen, and repositioning the PEG tube. The technical skill involved was not significantly different from that needed to place the PEG tube in the first place. It is important to utilize carbon dioxide insufflation if pneumoperitoneum is expected and to observe the abdominal pressure closely. This procedure was performed at the patient’s bedside under conscious sedation.7 Alternatively, the patient would have required a

general anesthetic agent and a laparoscopy or laparotomy to reposition the tube.

Additional avenues currently available are judiciously entering the peritoneal (or thoracic) cavity to interrogate selected fistulae or anastomotic leaks, possible irrigation, and closure by stenting, clipping, or suturing. The same can be done for iatrogenic perforations following endoscopic procedures. Transgastric lavage and drainage of pancreatic necrosis in a fluid phase with sepsis can have a dramatic benefit. The safety of performing a transgastric staging peritoneoscopy prior to a pancreaticoduodenectomy has also been extensively demonstrated.9

Of note, all of the staging peritoneoscopies have been performed in the operating room with the intention of performing a gastric anastomosis at the endoscopic gastrostomy site, thus avoiding endoscopic closure. Introduction of the submucosal endoscopic mucosal flap technique for safe offset access to the peritoneum may provide an expanded margin of safety and a larger operator pool.

What Procedures Can Minimally Invasive Surgeons Perform That Are New and Meet an Unmet Need? Many minimally invasive surgeons also perform endo-scopy and PEG placement. They can immediately start using the technique outlined above, facilitated by the familiar environment of the peritoneal cavity, albeit with a different visuospatial orientation.

Figure 1. Contributions, interactions, and possible future developments in interventional techniques.

NOTES=natural orifice translumenal endoscopic surgery.

Laparoscopy

Endoscopy

Single-port laparoscopy

Next-generation endoscopyCatheter-based techniques,�exible and mini-robotics

NOTES

Figure 1. Contributions, interactions and possible future developments.Reproduced, with permission24.

SINGLE-PORT SURGERYDuring the development of NOTES, the single-incision laparoscopy trocar was introduced as a

new scarless approach and considered as a spin-off of all NOTES-related research. Due to the

technical skills required for NOTES procedures and the slow development of NOTES devices, the

field of medical practitioners who could easily adopt to NOTES did not appear to be very large.

With the introduction of Single-Port trocars these problems were partially overcome. One of

the most important advantages of single-incision laparoscopic surgery (SILS) over NOTES is

the possibility to use conventional laparoscopic instruments. This has currently led to an overall

greater acceptance of SILS than NOTES 43-46. The market for SILS is projected to encompass 25%

of all laparoscopy procedures by 2014, with many more surgeons able to perform this approach

than NOTES24. Using SILS, multiport laparoscopic procedures can be performed through one

small incision, often hidden in the umbilicus. A SILS port can also be used at a future ileo- or

colostomy site or even transanally as discussed in this thesis.

However, many of the previously mentioned challenges during NOTES procedures are also

applicable to the principle of SILS. But the challenges during SILS are probably easier to

overcome and therefore SILS can be seen as an intermediate step in the development and

implementation of NOTES. SILS results in a minor scar when used at the umbilicus, but potential

complications like a wound infection or a postoperative hernia are still possible.

The SILS technique can be used for a wide range of laparoscopic procedures. Pioneers with

the SILS technique all started to utilise this technique for cholecystectomies47-49 and to a

lesser extent appendctomies50 and in urology51. As discussed earlier, loss of triangulation and

spatial orientation has to be overcome. If two straight instruments are used in a SILS port

during a dissection in a small area, like a cholecystectomy, clashing of the instruments is

unavoidable. By using roticulating instruments, a wider range of motion could be created at

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the tip of the instruments. However, roticulating instruments also increase the complexity of

the procedure (Fig 2).

OUTLINE OF ThIS ThESIS The aim of this thesis is to study the introduction of new minimal invasive techniques such

as NOTES and SILS, that can be used within the field of abdominal surgery and in particular

laparoscopic surgery.

In chapter 2 we evaluate our initial experiences with the SILS trocar for cholecystectomies. In

a case-control setting, the SILS cholecystectomy is compared to the conventional four port

laparoscopic cholecystectomy.

As our experience increased with the SILS technique, we also started to perform single incision

laparoscopic colectomies (SILC). It was first used for benign indications, but we rapidly expanded

to malignant indications. In chapter 3 we discuss the results of our first 50 consecutive cases.

One of the most performed SILC procedures is a right colectomy. Chapter 4 is a two centre,

prospective case control study in which the short-term surgical outcomes after SILC and

multiport laparoscopic right colectomy are evaluated.

Our research group is the first group in the Netherlands to perform a hybrid-transvaginal

cholecystectomy on a regular basis. In chapter 5 the feasibility of this procedure is investigated.

Chapter 6 evaluates the clinical outcomes of our first year performing transvaginal

cholecystectomies. Patient related outcomes such as body image and cosmesis are also evaluated.

In chapter 7 we evaluate the clinical and cosmetic outcomes of a case control study comparing

single incision, transvaginal and conventional laparoscopic techniques for cholecystectomy.

Transanal endoscopic microsurgery (TEM) is widely used for the excision of both benign and

malignant rectal tumours. TEM is relatively expensive and can be a challenging technique. Even

Figure 2. multiport laparoscopy (A) versus SILS (B-E) hand instruments and orientations.Reproduced, with permission52.

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1though not developed for transanal use, the SILS port could be ideal because of its shape and texture.

Chapter 8 is a feasibility study in which a SILS port is used for transanal resection of large polyps.

In patients with rectal cancer it can be difficult to dissect the rectum below the tumor. In chapter

9 we discuss the results of a feasibility study in which we conduct a hybrid NOTES procedure to

mobilise the rectum transrectally with the use of a single port in the rectum.

The general discussion (chapter 10) summarizes the main findings of this thesis and discusses

future perspectives.

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