Inflammatory bowel disease (IBD) is broadly classified into two major disorders: Crohn’s Disease (regional enteritis) and Ulcerative Colitis (UC). Crohn’s disease (CD) can affect any portion of the alimentary tract from mouth to anus while UC affects only the colon. The two disorders have unique pathologic and clinical characteristics though at times, distinction between the two can present a diagnostic challenge. Surgical decision making thus depends upon an accurate diagnosis so that appropriate counseling may be provided and the appropriate intervention recommended.
The detailed diagnostic algorithm of IBD in children is beyond the scope of this topic. It is made through thoughtful collaboration between the Pediatrician and Gastroenterologist with additional input and guidance provided by a Pediatric Radiologist, Pathologist and Surgeon. Diagnosis is made with a thorough review of the clinical history, analysis of IBD specific laboratory panels (inflammatory markers, nutritional labs and antibody testing), diagnostic imaging and upper and lower gastrointestinal endoscopy (both flexible and capsule) from which histologic analysis of both diseased areas and grossly unaffected random samples can be performed.
Once the diagnosis is made, a decision can be made regarding the need for and/or timing of operative intervention. In most instances, the indication for operative intervention is disease refractory to medical therapy. If this can be anticipated, one can address the patient’s nutritional status and steroid exposure preoperatively in order to reduce perioperative morbidity. Excluding fulminant toxic colitis, there is a role for a minimally invasive approach to most operations for IBD. These will be addressed below.
Minimally Invasive Approaches to Ulcerative Colitis
The definitive treatment of UC is total proctocolectomy. While historically this was performed with ileostomy, restorative ileal pouch with anal anastomosis (IPAA) is now standard of care following colectomy. This can be performed in one, two or three stages. Single stage proctocolectomy with IPAA should be reserved for a highly selected group of patients with an experienced surgeon as technical complications and pouch failure are greater without the protection of a loop ileostomy. More commonly, patients undergo proctocolectomy with IPAA and diverting ileostomy followed by ileostomy closure (the second stage) 8-12 weeks later. The three-stage procedure is reserved for patients with severe fulminant colitis or non-elective cases in which total abdominal colectomy with ileostomy is performed first. Stage two includes completion proctectomy with IPAA leaving ileostomy closure for stage three. The minimally invasive approach is applicable to each step of this operation.
The minimally invasive approach to proctocolectomy is well described and can be performed with or without hand-assistance. Used more commonly in adults, the smaller size of the pediatric and adolescent patient may complicate the use of the standard hand-assist port. Standard 5mm and 10-12mm laparoscopic trocars may be used for this operation. Most will employ a standard umbilical site, bilateral lower abdominal trocars (the right lower quadrant location becoming the site of the ileostomy) and a supraumbilical trocar off-midline. As some have become more comfortable with single-site laparoscopy, we have seen descriptions of proctocolectomy with IPAA being performed using a single-site device through the right lower quadrant ileostomy incision.
Proctocolectomy is facilitated by the use of an energy source (electrosurgical or ultrasonic) to take the vascular pedicles and the liberal use of patient positioning to facilitate exposure. In the pelvis, laparoscopy provides superior visualization allowing constant visualization of the ureters and avoidance of the deep pelvic nerves. Retrieval of the specimen can be performed through the hand-assist site, the right lower quadrant ileostomy incision or transanally. Construction of the ileal reservoir is performed extracorporeally. The ileoanal anastomosis can be performed using either a stapled or hand-sewn technique. The stapled technique connects the j-pouch to a short rectal cuff using a circular stapler passed transanally. This obligatorily leaves a small strip of rectal mucosa and the anal transition zone intact. When the small pelvis of the child prevents transabdominal stapling of the rectal cuff, a technique of transabdominal endorectal mucosectomy with extracorporeal rectal stapling can be employed to complete the distal resection margin. A circular stapler then completes the anastomosis of the ileal reservoir to the distal rectal mucosal cuff.
An alternative to the stapled anastomosis is a formal rectal mucosectomy and handsewn ileoanal anastomosis performed from a perineal approach. This technique can be employed while still using a minimally invasive approach for the proctocolectomy as described above. Proponents of the stapled technique site shorter operative times and better post-operative continence compared to the hand-sewn anastomosis. Critics point out the risk (<1% incidence) of malignant transformation in the retained rectal cuff and anal transition zone. Three adult randomized controlled trials comparing stapled to hand-sewn IPAA have failed to demonstrate a difference in functional recovery, however, more recent meta-analysis suggest improved nocturnal continence with the stapled technique.
Minimally Invasive Approaches to Crohn’s Disease
Unlike ulcerative colitis, bowel resection in Crohn’s disease is not curative of the underlying condition. In those with primarily small bowel disease, seventy percent of patients will undergo bowel resection at some time during their lives. One third of these patients will require at least one additional resection. As in ulcerative colitis, the indications for operative intervention in Crohn’s disease include failure of medical management. However, intervention in Crohn’s disease will more commonly be directed towards disease related complications such as obstruction, perforation with abscess or enteric fistula disease. Pre-operative considerations in the IBD population ought to specifically address nutrition status, current steroid exposure and comorbid conditions. These considerations will aid in intraoperative decision making when questions of primary anastomosis versus cutaneous enterostomy arise.
Laparoscopy is well suited to address the operative needs of children with Crohn’s disease. Advocates point to improved postoperative pain control, decreased post-operative adhesions and more rapid normalization of diet. There is a deficiency of prospective data directing the use of laparoscopy in children with IBD. However, the use of laparoscopy for small bowel Crohn’s disease in adults is well published and supported by numerous observational studies. It has also been the subject of the Cochrane Collaboration in which review of the two available randomized controlled trials comparing open and laparoscopic treatment of Crohn’s disease revealed no difference in measured outcomes.
The most common intra-abdominal intervention in the Crohn’s population is ileocolic resection with anastomosis. This operation is readily approached with a 3 trocar technique utilizing an umbilical port, suprapubic port and left lower quadrant port. Increasingly there are reports of single-site laparoscopy being used for this operation with good results. Whichever access is selected, most will perform an extensive laparoscopic ileocolic mobilization with exteriorization of the bowel through either a midline extension of a trocar site or a lower-abdominal transverse Pfannenstiel incision. The anastomosis is then created extracorporeally in a stapled or hand-sewn fashion. Bowel resection in Crohn’s disease is aimed at treating the causative lesion and preserving intestinal length whenever possible. When addressing non-ileocolic lesions, similar principals apply. Trocar placement is selected such that the lesion of interest is triangulated. Including a vertically oriented umbilical incision or a low transverse incision for trocar positioning will provide an improved cosmetic result when extending an incision for extracorporeal anastomosis.
Laparoscopy is also indicated in complicated Crohn’s disease. Complicated small bowel disease with intraabdominal abscess or fistula can safely be approached in a minimally invasive fashion. Abscess cavities can be taken down and irrigated laparoscopically. Fistulous disease can be exteriorized and resected similar to ileocolic resections.
Laparoscopy adds great value to the operative management of inflammatory bowel disease. In Crohn’s disaease, its greatest advantage lies is in its ability to facilitate extensive mobilization through minimal access. With ulcerative colitis, it is able to provide unmatched visualization to the low pelvic dissection. In all instances, the use of laparoscopy minimizes incisions thus decreasing post-operative wound complications and pain. Hybrid techniques combining laparoscopic dissection and mobilization with the extracorporeal construction of anastomoses and pouches take advantage of the best of both open and minimally invasive techniques. While great efforts have been made to prospectively study laparoscopy in adults with IBD, we must strive to critically assess our outcomes in the pediatric population.