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ORIGINAL ARTICLE
Year : 2021 | Volume
: 17
| Issue : 2 | Page : 180-187
Training for laparoscopic colorectal surgery creating an appropriate porcine model and curriculum for training
Tehemton Erach Udwadia
Center of Excellence for Minimal Access Surgery Training; Department of Surgery, Grant Medical College, Grant Medical College and J.J. Hospital; Department of Surgery, B. D. Petit Parsee General Hospital, Breach Candy Hospital, Mumbai, Maharashtra, India
Correspondence Address:
Dr. Tehemton Erach Udwadia
Flat No. 10, Normandie, Carmichael Road, Mumbai - 400 026, Maharashtra
India
Source of Support: None, Conflict of Interest: None
CheckDOI: 10.4103/jmas.JMAS_86_20
Background: Laparoscopic colorectal surgery (LCRS) was first described in 1991, and its safety, efficacy and patient benefit were adequately documented in literature. However, its penetration and acceptability is poor in most countries, due to its long learning curve and lack of surgeons training and confidence. A Minimal Access Surgery (MAS) Training Center in Mumbai has over the last 7 years trained more than 8000 surgeons in various MAS specialities. The centre has initiated courses for LCRS training.
Materials and Methods: The anatomy of the pig colon is very different from human anatomy. The pig colon anatomy is altered to mimic human colon anatomy in the porcine abdomen, permitting hands-on practice on most laparoscopic colorectal surgical procedures, as part of the LCRS training course, under mentorship of expert faculty, who simultaneously assess participants performance.
Results: Each participant performs and assists for at least three procedures and is evaluated at each step of the procedure by a structured format. The overall evaluation by Faculty which though subjective, is detailed and favourable. Feedback of each participant is good and acceptable as a very helpful course.
Conclusion: This porcine model is ideal for hands-on training for LCRS. Participants achieve a good degree of skill level and confidence in performing LCRS procedures on fresh bleeding porcine cadaver models. The centre is factual and pragmatic and stresses that it needs more than a course to make a safe surgeon; operation room mentorship is the finishing school.
Keywords: Laparoscopic colorerctal surgery, laparoscopic training, porcine model
Considering that thefirst laparoscopic colorectal surgery (LCRS) was done in 1991[1] the conversion from open colorectal surgery (OCRS) to LCRS has been slow and hesitant, compared to most abdominal surgery, with an adoption rate well below 20% worldwide. There are gross differences in literature on the percentage of penetration of LCRS country-wise as also ‘world-wise'. Data is difficult to collect and collate, since the vast majority of countries have no Registry for LCRS. Lack of training facilities applies as strongly to developed as to developing countries for poor penetration.[2] Figures of about 20% ‘worldwide’ or ‘global’ penetration are often mentioned. Considering that the Lancet Commission on Rural Surgery Stresses that over five billion people have no access to safe surgery,[3] any such figures are to be viewed with true pragmatic acceptance of sad reality. Granting the higher complexities of LCRS, in view of the accepted patient benefit and cost reduction[4],[5],[6],[7],[8] the low uptake of LCRS in most countries merits correction.[9] The high learning curve of LCRS[10],[11] makes the traditional Halstedian mentor-trainee structure for the entire LCRS training program impractical, besides being ethically inappropriate and adding considerably to OR expense.[12],[13]
Several training modalities, outside the OR, to prepare the trainee transit to safe OR performance have been used. Virtual reality (VR), cadaver models, box trainers, animal models have all been used with varying degrees of effectiveness. The limiting factor for moving from open to LCRS very often is the high learning curve and the surgeon's skill deficiency for LCRS, stressing the importance of structured training in a risk-free setting, using appropriate simulation.[14],[15]
LCRS creates peculiar and specific challenges and demands. Multiple abdominal quadrants are involved in the procedure, particularly for extensive mobilisation of bowel, or if a colostomy is required. This has specific relevance to port placement and team coordination. Besides extensive bowel mobilisation, vessels need to be identified and divided, retroperitoneal structures preserved, the bowel resected and the specimen retrieved. Bowel ends need to be anastomosed, extra- or intracorporeally. Lymph node clearance in malignancy and complex pathology, especially in inflammatory lesions adds to the challenges. LCRS is advanced complex surgery, which needs advanced simulation training.
The procedures performed by LCRS are (1) anterior resection for sigmoid, high rectal lesions, (2) lap assisted APR, (3) right colectomy, (4) left colectomy, (5) transverse colectomy, (6) colostomy, (7) repair prolapse rectum (rectopexy), (8) repair para-stomal hernia and (9) ileostomy.
LCRS has less blood loss than OCRS but takes longer, has less pain, faster return of bowel activity, shorter hospital stays[16],[17],[18] and equal if not lower morbidity and mortality as OCRS.[19] There is convincing evidence that the highest morbidity and mortality, in all colorectal surgery, is in cases of LCRS converted to open surgery.[16] This makes it mandatory that patient selection for LCRS is done with care and pragmatic evaluation of the patient, the pathology and the surgeons’ experience and ability. LCRS is a team procedure, ideally the entire OR Team should train together at the same time.
It must be appreciated that the benefit evaluation/comparison is not of the simulator, but the quality of the simulation provided. Literature is heavily burdened with, comparative studies of innumerable simulation devices for LCRS. In common use are:
Human cadaver would logically appear ideal for simulation.[20] Availability, complex legal issues, high cost, make it available in a tiny miniscule of workplacesVR. Literature lauds the value of VR simulators.[21],[22] However, in actual practice, participants predominantly prefer training on tissue models. VR does not permit teamwork, a necessity in training, has poor haptics, poor appreciation of dissection and tissue planes and the perfection of the camera operation at VR is seldom reproduceable in real life during training! Its main advantage is objective, measurable assessment[23]Box trainer is excellent for basic laparoscopy but is unequal to the demands of LCRS. Simulation human cadaver models in box-trainers lack feel of reality and need construction, can be used for only one procedure and need access to cadavers[20]Live animals give excellent haptics, tissue feel. However, use of live animals is prohibited by law in India, with strong deterrent punishment.At a not-for-profit or commerce, autonomous training centre for Minimal Access Surgery (MAS) in Mumbai, run by surgeons for surgeons, over the last 7 years more than 8000 surgeons have participated in training in sixteen surgical specialities in which MAS is practiced. All models, inanimate and animal for all different courses taught, have been devised/modified/created at the centre. The centre felt the need to create a model suitable for training in LCRS, which is cost effective and provides appropriate training in most LCRS procedures. Courses for LCRS are being conducted on a fresh porcine model with anatomy altered to approximate as far as possible human colorectal anatomy. The performance evaluation of this porcine model by faculty and the feedback of all participants is favorable.
Materials and MethodsFresh porcine cadaver simulation model
The colorectal anatomy of the pig is very different from the human.[24],[25] With some effort and ingenuity, the pig anatomy needs to be altered to appropriately align with human anatomy. The pig has an ileocecal junction, a caecum like the human (with no appendix) and the caecum progresses to a spiral, intraperitoneal, coiled large bowel with two tenia [Figure 1]a and [Figure 1]b. The mass of coiled bowel at its distal end opens into a sigmoid colon, very like the human, and progresses to the rectum. The pig ileocecal junction is firmly tethered to the posterior peritoneum, the junction of the terminal colon with the sigmoid colon is also tethered to the posterior peritoneal abdominal wall, anchoring the commencement and the termination of the spiral intraperitoneal large bowel. This spiral colon loop has no demarcated anterior, transverse, descending colon. With this intraperitoneal colon gathered in a tight spiral ball the colon mesentery is very short and contracted, intraperitoneal. The ileocolic vessels have a normal mesentery as do the terminal part of the inferior mesentery vessels supplying the sigmoid colon and rectum. The mesentery of the rest of the colon has numerous small parallel vessels, with no clear right, mid or left colic vessels [Figure 2]. Hence, there is very limited scope for performing medial to lateral mesentery dissection. A medial to lateral vascular and lymph node dissection can only be done for the sigmoid colon and for the ileum and caecum. This is a drawback of this model and efforts are in progress to overcome this deficiency.
Figure 1: The pig colon is a spiral, coiled intraperitoneal bowel loop commencing from a ‘normal’ placed cecum and terminating in a ‘normal’ placed descending colon–sigmoid junction. The distal caecum and proximal sigmoid are firmly tethered to the posterior abdominal wall, giving a firm fixed base for the entire intraperitoneal colon loop. No demarcation into ascending, transverse, descending colon
Figure 2: The colon mesentery is bunched within the spiral loop, with no arcade, and narrow long parallel supplying vessels, no right colic, mid colic, left colic vessels. The terminal ileocolic and terminal inferior mesenteric vessels are present supplying the ileocaecal region and sigmoid and rectum respectively. During the procedure these pulsating vessels need to be identified, dissected and dividedThe coiled spiral mass of colon is gently separated into a long length of colon and is emptied of gas and fecal matter. Moving proximally from the sigmoid, a length of bowel which would represent the descending colon, splenic flexure and the distal half of the transverse colon is measured. The posterior peritoneum which tethers the proximal sigmoid is incised vertically upwards from the proximal sigmoid up to the spleen, a retro-peritoneal space is created to accommodate the new ‘descending colon’ [Figure 3]a. The peritoneal incision is sutured to position the new retroperitoneal descending colon reaching cephalad to the splenic flexure [Figure 3]b, which is continued intraperitoneally as the distal transverse colon. Similarly, on the right side, adjacent to the caecum the posterior peritoneum is incised up to the liver and the bowel distal to the caecum, the new ‘ascending colon’ is positioned retroperitoneally up to the hepatic flexure and the peritoneal incision is sutured. The loop beyond the hepatic flexure of the colon continues as the intraperitoneal proximal transverse colon. The length of pig colon is too long to be preserved as a human like transverse colon. Making an adequate loop to represent the transverse colon the surplus bowel is excised and the proximal and distal ends of the ‘transverse colon’ anastomosed, completing the creation of ‘human’ colon anatomy. The retroperitoneal anatomy – duodenum, ureter, vessels, nerves, is identical to human anatomy, giving a life-like experience.
Figure 3: Creation of human colon anatomy. (a) The coiled colon loops are separated to create one long straight colon. The posterior peritoneum is incised from the sigmoid to the spleen. A retroperitoneal space is created to accommodate the ‘descending colon’ up to the spleen, starting at the sigmoid. (b) The incised peritoneum is sutured to maintain a retroperitoneal position for the descending colon as in the human. Beyond the splenic flexure, the bowel continues intraperitoneally as the distal transverse colonThrough a small incision in a tenia a ‘tumour’ is implanted in either the sigmoid colon/descending colon/ascending colon (piece of broccoli or piece of rolled up rubber glove), which is sutured to the mucosa to ensure that a specific area for resection is identified. The small tenia incision is sutured. The abdominal incision is closed airtight, with adequate area free for trocar placement [Figure 4]a and [Figure 4]b.
Figure 4: (a) The abdominal incision gives adequate exposure to recreate abdominal anatomy, after which it is closed airtight. (b) The incision does not interfere with port placementThe descending aorta is cannulated to above the origin of the superior mesenteric artery and occluded, to enable perfusion of the superior and inferior mesenteric vessels at 80 pulsation a minute with a blood like fluid at a pressure of 120/80 mmHg, to mimic as best as possible, actual OR conditions. The trachea could be intubated for lung insufflation for further ‘in vivo’ feel.
Cost
To an autonomous training centre, run by surgeons for surgeons, supported by an academic fund, which is not for profit, not for commerce, cost is a major issue. Compared to the cost of the cadaver, VR simulators, box-trainer with ex-vivo human simulation and live animals,[20] this fresh porcine cadaver is by far the most cost-effective and appropriate model for training for most laparoscopic colo-rectal surgical procedures, all performed in the same one animal.
Course curriculum
Pre-course information to participants
Since this is an advanced surgery course, only participants with some experience in OCRS, proficiency in laparoscopic surgery, ability to perform laparoscopic suturing are accepted for the course. Video clips and relevant literature are sent to participants on their registration for the course as preparation for the course. This is team surgery and surgeons who wish to work as a team are advised to come together and could bring their OR scrub nurse to assist them.
Hands-on sessions
At the start of the 1st days hands-on session Faculty demonstrates anterior resection of the sigmoid to display and emphasise the sequential steps, choreography, precise tissue dissection, use of staplers, safety essentials, and finer details of the procedure on the large demonstration monitor.
This simulation model provides a fresh pig cadaver with colon anatomy approximating the human [Figure 5] and [Figure 6], tissue of normal haptics and feel. All tissue dissection is done with monopolar diathermy using a hook dissector and scissors, equipment readily available in any part of the world where MAS is practiced. After vascular division [Figure 7] the bowel is mobilised medial to lateral, by hook dissection of normal tissue planes to complete mobilisation of sigmoid/rectum [Figure 8]. The retroperitoneal descending colon is mobilised up to the splenic flexure [Figure 9].
Figure 5: Surgeons first view for anterior resection. The large fluffy bladder needs to be hitched to the anterior wall to visualise deep pelvic dissection and for sigmoid and rectal mobilisation
Figure 6: The porcine junction of descending bowel and sigmoid is tethered to the posterior wall by this band. The implanted tumour is seen in the descending colon
Figure 7: Pulsating inferior mesenteric artery, with blood flow, being divided
Figure 8: Pelvic dissection. Sigmoid colon lifted and being mobilised. Importance of using a fresh cadaver is seen in normal tissue planes. The entire procedure is done with monopolar diathermy using a hook dissector, an energy source and instrument available all over the world where MAS is being done
Figure 9: Mobilisation of descending colon has reached the splenic flexure, which is being mobilised from the large spleen, which needs elevationThe distal end is stapler divided [Figure 10]a and [Figure 10]b and the length to be resected exteriorised through a small incision [Figure 11]. The incision needs to be protected from the specimen during retrieval. The proximal stump is fixed to the anvil of the circular stapler with a purse string suture and returned to the abdominal cavity. The abdominal wall incision is closed, and pneumoperitoneum re-created. Anastomosis between the rectal stump and proximal bowel is completed using a curved circular stapler [Figure 12]. Anastomosis security is checked by the ‘leak test’ and inspection of the two donuts [Figure 13].
Figure 10: (a) Stapler locked at the recto-sigmoid junction. (b) Rectal pouch being created after firing of the stapler
Figure 11: Retrieval of specimen through a small incision, after deflating pneumoperitoneum. Incision needs protection from contact with specimen (not shown here). The tumour is seen in the resected specimen
Figure 12: External view of circular stapler. Internal view showing penetrating of rectal stump and docking of circular stapler in progress
Figure 13: External and internal view of circular stapler anastomosis. Donuts being inspected after stapler is removedThe simulation creates as best as possible the real experience. All procedures are performed by participants on the model under Faculty guidance [Figure 14]. Each model is suitable for training for anterior resection of sigmoid or upper rectal lesions, left colectomy, right colectomy, colostomy or ileostomy and rectopexy [Figure 15] and permits all above procedure for training to be carried out on the same one model, making it eminently cost-effective. Procedures done by participants are recorded for later discussion. The implanted ‘tumour’ gives training in appropriate mobilisation and resection. It is the training dictum of this centre– practice does not make perfect, perfect practice makes perfect.
Figure 14: View of hands-on training. Five tables with one Faculty for every two participants per table. A lab technician helps as scrub nurse. Surgeon (inserting trocar), assistant as camera operator, Faculty mentoring, assessing
Figure 15: Rectopexy. (a) Extensive rectal mobilisation, rectum drawn well up from pelvis and nerves identified. Mesh fixed to peri-sacral tissue with staplers. (b) mesh fixed to rectum with sutures. This procedure is being done without perfusion of inferior mesenteric artery, to show importance of arterial perfusion for live feel during the procedure, as seen in all preceding figures of anterior resectionAt each lab table, one participant is the surgeon, the partner the camera operator/assistant. For the next procedure the roles are reversed. On the 2nd day the procedures are arranged so that every participant performs, as also assists, at each procedure during the course. Only ten participants are selected for this course as it requires a faculty: participant ratio of 1:2 to ensure adequate mentoring and careful performance evaluation of every step of the procedure. One laboratory technician stands in as scrub nurses at each table. Laparoscopic transverse colectomy and laparoscopic repair para-stomal hernia are not taught on this model.
Cognitive skills
While giving due importance to hand skill development, importance is equally given to cognitive skills. Discussions on anatomy, pathology, possible complications, team-effort, conversion, radiology, stoma care, energy sources, staplers are essential, even at the cost of some loss of hands-on time.
At the end of the final hands-on session, selected video clips of the participants performance are displayed for discussion. The hands-on proficiency level of each participant as recorded over 2 days is factually assessed. Multiple choice question tests, feedback from faculty and from participants is taken. A certificate of attendance for the course is given to the participants in addition to a set of training videos and literature. Participants and Faculty form a WhatsApp group to monitor individual ongoing progress, for discussion, mentoring and for Alumni contact.
ResultsResults are documented in an excel format. Both the didactic course and the hands-on skills course are graded on specific criteria by faculty. For the didactic course, grading is given on knowledge, understanding, participation in discussions, aptitude, seeking answers to their questions. For the hands-on skills course, creating pneumoperitoneum, trocar placements, camera operation, instrument choreography, recognition of anatomy, use of both hands, gentleness, tissue dissection, sequence of procedure steps, speed, precision are all taken into account. While speed is given grading, speed never has priority over precision.
An important aspect of evaluation of results is provided by the participant in the feed-back form. When asked on scale of 1–10 (10 being better), that the participant has acquired the knowledge, requisite skill and the technical ability for LCRS, and the degree of confidence the course has provided, an honest answer is the true result of the course. Even if in a minority of one, the Author is convinced surgical performance is best seen, appreciated and graded, and may not, at just one session, be given a ‘mathematical’ score.
DiscussionLCRS is performed to a far less extent than is its due as a proven method of improving patient care. The main reason for this is that most surgeons are aware it is a complex advanced procedure and are inhibited as they lack confidence and training. Effort needs to made to bring LCRS within the scope of the average MAS surgeon who is doing OCRS and reasonably advanced MAS. Hands-on experience on this porcine model where the trainee performs and assists as a team at most LCRS procedures is an essential, but not the sole part of the curriculum. Discussions on fundamental background knowledge like anatomy, pathology, radiology, seeing live surgery, videos, complications, learning tips and tricks and more, is as important a part of the curriculum. The aim of any training program should be to help develop sound surgeons, not mere technical artists. No course should expect or portend to make a trainee ready for instant transit to the OR. The transition for safe surgery needs more. If a training course can give the trainee total confidence, after the course, of having achieved the technical ability, manual skill and overall knowledge to perform LCRS, and inspire and instill the determination and belief that it will benefit the patient if the trainee learn further, to safely do so, the author feels the course has served its purpose. The alumni tie with the centre helps in further learning.
Literature is replete and overburdened with various simulators or methods of simulation for LCRS being compared to one another, each one claiming to be better. This is the ultimate absurdity of MAS training. Anyone involved in MAS training must appreciate that various good simulation methods are not competitive, they are complementary. This porcine model is but one method which helps in the transit of the trainee to smooth and safe OR performance, which is the ultimate aim of all MAS training. Furthermore, to be stressed is that though hand mastery is an essential part of OR performance, cognitive skills are equally, or rather more important and should be inculcated in the course curriculum. Hand skills can be taught, performed and perfected in the training centre. The ultimate cognitive skill development of the surgeon is by mentorship and proctorship in the OR environment and experience. The Sushruta,[26] the Halstedian methods of surgical training[27] in the making of the complete surgeon, will never be bettered.
ConclusionThere is convincing and accepted evidence that LRCS is as safe as OCRS, when done by trained, experienced laparoscopic surgeons, and has comparable anastomotic safety. LRCS takes longer operative time and has higher OR cost. On the other hand LRCS has significantly less blood loss, less pain, earlier return of bowel activity, shorter hospital stay. in terms of post-operative evaluation, there is comparable lymph node clearance, free resected margins, and survival rate on follow up in malignancy. In this scenario, it raises the question why the penetration why the penetration of LCRS lags behind in several countries? The answer lies with the surgeons’ reluctance to exert to gain the proficiency level required to give the patient the benefit of LCRS. LRCS has a longer learning curve, requires patience and perseverance of a greater order and the maturity and cognitive skills acquired over time.
Good training involves much more than simulation training courses. A course will provide hand proficiency and precision, but the surgical foundation is based on mentorship, proctorship which gives clinical exposure of various situations, pathology, and need for tailored procedures. This does not detract from the necessity for perfectly structured LCRS courses as described in this paper, for they shorten the training process appreciably by giving a high level of manual skill and a sense of purpose and confidence. The porcine model created for this course is unique as it permits true-to-life performance of most colorectal surgical procedures. No mention of even a remotely similar porcine model for LCRS was found in the literature. The model is not difficult to create and with vascular pulsating blood flow and respiratory movement mimics the OR conditions very closely.
Acknowledgements
Couse Convener – Dr Kaiomarz Balsara, Co-Convener – Dr Prajesh Bhuta, Laparo-Colorectal Surgeons, who assessed the prototype models and made video recordings for training programs of every step of each procedure. Dr Balsara has been involved from the conceptualisation of this Course and has evaluated and made suggestions for the manuscript. Apart from professional expertise all course faculty display commendable passion and dedication for teaching. They are the core of the courseMr Pramod Chougule, Mr Vaibhav Bugade, Mr Pradeep Bhangre, Laboratory Technicians and their laboratory team. Without their dedication, expertise and ingenuity this Training Course would not be possible. The essence of the course is fresh porcine cadavers. After being taught the procedure, they open the abdomen of the fresh cadaver, evacuate the colon gas and faecal matter, alter anatomy to create six cadaver models, create vascular perfusion within one hour, close the abdomen airtight. They provide fresh cadavers for the hands-on to provide optimal tissue feel and dissection on ‘bleeding’ modelsDr Suchitra Bindoria – Director and Dr Nikhil Patel – Manager- Technical Operation, for unfailing support and coordination of infra-structure, material, lab time and course implementationDr Sneha Nikam – Assistant Manager-Technical, for efficient and enthusiastic help with References, article preparation, submission and ongoing participant alumni contactMrs Megha Patil – Secretary to Chairman, for prompt efficient secretarial assistance.Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References
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