Anvil Ct-121
Enrique Vasquez
Minimizing the insults to the abdominal wall is intuitively accompanied by improved outcomes and, indeed, the laparoscopic approach in colorectal surgery has proven its benefits over open surgery in terms of lower postoperative pain, faster recovery and better cosmetic results. [1],[2],[3] The rationale for further scar-less surgery is that countdown in number and size of port access to the abdominal cavity may be advantageous not only from the cosmetic aspect but also in order to minimize the risk of complications such as wound pain and infections as well as incision hernia and internal adhesion formation. [4]
The main difference to retain is between "single-incision surgery," in which a single skin incision is made and ports pass individually through multiple fascial incisions and "single port surgery," in which instruments are passed into a unique port into a single fascia wound. In MISS, therefore, all instruments come from a unique entry point with almost parallel orientation. This raises a number of specific new challenges compared with the laparoscopic conventional approach. A reduced capacity for triangulation is the most claimed issue, with its imposed need to operate sometimes with crossed hands. Furthermore, the repeated conflicts between the shafts of the instruments, the gastroenterologist-like in-axis view offered by the telescope running parallel to operating instruments and the difficulties to achieve a correct exposure and to apply the necessary traction to tissues without a supplementary instrument all complete the list of the major problems. The use therefore of this new approach for complex colorectal procedures implying multiple-field dissections, resection and retrieval of huge specimens as well as for the construction of anastomosis could therefore understandingly be viewed as difficult to implement, especially for oncological cases.
MISS has however been applied to colorectal surgery in the 2 years since Professor Leroy described and standardized the first single-port sigmoidectomy [15] and performed the first totally laparoscopic MISS sigmoidectomy with endoluminal placement of the anvil of the circular stapler to allow intracorporeal anastomosis. [16] In a review published this year, Leblanc et al.[17] have reported data on 17 patients from nine available studies and even since then, due to the high level of interest in this field, more and more reports and small series have been published. Most recently, the Oxford group have published the first series of MISS total colectomy for patients with medically uncontrolled colitis, which involves a standardized operative approach specifically formatted to supervene the limitations of the confined operative approach. [18]
Our aim here is to benchmark the current state of the art of MISS on colorectal surgery, analysing clinical reports and case series, paying attention to initial operative outcomes and oncological preliminary results.
From July 2008 to July 2010, a total of 29 articles and one systematic review have been published in the English literature on single-access laparoscopic colorectal surgery. Fourteen technical notes with one patient and 14 case series (one series [19] being the extension of a previous published one [20] ) were analysed. One series in robotic single-incision colorectal surgery has been published. [21] One ongoing randomized clinical trial has been identified. (Trial for single port versus conventional laparoscopic colectomy. "ClinicalTrials.gov" Identifier NCT01101672.) Therefore, a total of 149 patients (121 in MISS with single-port device and 28 in MISS without single-port device) have been reported by the time of the present review. The diagnostic and surgical procedure lists are shown in [Table - 1] and [Table - 2]. In contrast, the last published systematic review on colorectal single-access surgery displayed data concerning 17 patients. [17] Outcomes in single-incision cases are displayed in [Table - 3]. [Table - 4] and [Table - 5] summarize the technical aspects and operative outcomes of MISS with single-port procedures, respectively. Results concerning the number of harvested nodes, specimen length and resection margins in the case performed for malignancy are displayed in [Table - 6].
In 2008, we demonstrated the feasibility and reproducibility of single-port sigmoidectomy in a porcine survival model involving six pigs. [15] The passage from bench to bed has been very rapid, with an increasing number of clinical reports of MISS in colorectal surgery. The complexity of colorectal surgery however makes more apparent the already recognized technical difficulties of single-access surgery. To summarize these aspects, the lack of triangulation and exposure, the in-axis view and the repeated conflicts between instruments are the most important challenges. A large variety of tricky and inventive solutions to overcome these difficulties has already been displayed in these preliminary studies, like the use of curved or roticulating instruments, sleeve ports, flexible tip scopes, magnetic retraction, intracorporeal fixing devices and/or the use of a robotic interface. An extensive analysis of technological unresolved issues is however beyond the aim of this review. Furthermore, these studies are highly inhomogeneous where technical aspects are concerned, showing that the technique is still in its infancy, and most of them present a lack of certain outcome measures that deserve to be discussed.
If one of the expected advantage of MISS surgery is the reduction of postoperative pain, one may be surprised that none of these reports assessed the postoperative pain using a validated tool such as the Visual Analogue Scale, and only in one did we find specifications concerning the analgesic requirement. [22] Concerning the incision length, it would be of interest to specify systematically the length of the fascia incision that is often enlarged to permit the extraction of the specimen. It has recently been reported that a mid-line extraction site of the specimen in laparoscopic colorectal surgery greatly increases the risk of incision hernia compared with off-midline sites (midline 17.6% vs. off-midline 7.8%; P < 0.0002). [34] Podolsky et al., using the technique named SPA surgery reported two access site hernias in their series of 13 colorectal procedures (15.38%). [25] SPA implies the realization of three to four distant fascia incisions along with the mobilization of soft tissue flaps off the underlying fascia to create a quite large working space in which separate trocars are placed, offering a good triangulation. At the time of extraction of the specimen to place the anvil and/or perform an extracorporeal anastomosis, fascia incisions are connected, with the consequence of the creation of a point of potential weakness. Performing an extracorporeal anastomosis within a very small incision may be not only cumbersome but also traumatic for the colon and mesocolon; however, enlarging it too much may lead to a loss of the intended benefits. On the other hand, the conversion to hand-assisted laparoscopy with a 6-cm incision is probably to be considered out of the setting of minimally invasive surgery and, more realistically, be seen as a "video assisted minilaparotomy." It should of course be stated that the publications to date are initial experiences and therefore perhaps best viewed as proof of feasibility rather than proof of benefit.
Development and standardization of surgical platforms and techniques offering less-invasive and equally effective procedures is the common aim of physicians and engineers of surgical companies. Immediate reaction to novelties is normally a mix between enthusiasm and scepticism. Both reflect a merely intuitive appreciation without the whole vision of the possible implications. Especially in the surgical field, given the complex interactions between different actors (the patient, the surgeon, the companies, the health care system), the process of acceptance or rejection of a new technique is extremely delicate. Examination of this issue from different points of view may better explicate the concerns and challenges posed by this technique.
This wide acceptance of MISS converts into a high potential for developing the technique, driven by patient demand, and surgeons must be prepared and feel the urge to improve feasibility and safety of this approach. On the other hand, surgical instrument and technology companies are looking for establishing a convenient and competitive market. This is absolutely normal and positive results and improvements are possible only with tight and ethical cooperation with companies. Finally, health care systems have the duty to offer to the citizen the best of medical care, taking into account the economic aspect. This novel approach therefore has to prove a favourable cost/benefits ratio to gain widespread acceptance.
c80f0f1006