Gastroenterology and GI Surgery

Investigating Ileal Pouch-Anal Anastomosis and Pouch Dysfunction

    Dr. James Church

    Ileal pouch-anal anastomosis (IPAA) is an effective alternative to a permanent end ileostomy. In the more than 40 years since its inception, IPAA has been studied widely and yet, according to James M. Church, MD, there is still a lack of understanding of why and how the procedure works.

    “Without knowing how a pouch works, it is hard to come to grips with the reasons why it doesn’t work,” says Dr. Church, a renowned colorectal surgeon and Director of Research and Section Head of Hereditary Cancer and Familial Polyposis in the Division of Colorectal Surgery at NewYork-Presbyterian/Columbia University Irving Medical Center.

    In his recent research into the physiology of IPAA, Dr. Church maintains that the vulnerability of the procedure is its lack of propulsive peristalsis due not only to the division of the circular muscle layer of the bowel wall but also the anastomosis of a properistaltic limb to a retro peristaltic limb. “As a consequence, stool will only exit the pouch by the force of gravity or manual pressure on the low abdomen, or a strong Valsalva,” says Dr. Church.

    Colorectal surgery provides an opportunity to fix people and that’s what I like to do as a surgeon. I see patients and I put myself in their place. I see their anxiety. I see their pain. So anything I can do to reassure and comfort them I’m going to do.

    — Dr. James Church

    Furthermore, Dr. Church believes that understanding this facet of pouch physiology may lead to a clearer understanding of pouch dysfunction, including pouchitis. To that end, Dr. Church conducted a retrospective study of a cohort of patients who had undergone total proctocolectomy with ileal pouch anal anastomosis for familial adenomatous polyposis or ulcerative colitis who had trouble emptying their pouch. In his investigation, the results of which were published in the September 21, 2022, online issue of ANZ Journal of Surgery, Dr. Church detailed the patients’ presentations, treatments and outcomes.

    Patients were drawn from Dr. Church’s personal experience at the Cleveland Clinic Foundation, where he served as a staff colorectal surgeon before joining New York-Presbyterian and Columbia. All the patients had presented with symptoms suggesting poor pouch emptying and underwent clinical examination and pouchoscopy. Some patients had further testing that included contrast enema of the pouch, defecating pouchography, electromyography of the pelvic floor, and small bowel follow through. “Our hypothesis was that the underlying lack of any prograde peristalsis in an ileal pouch makes it very susceptible to any condition or behavior that promotes inefficient emptying,” says Dr. Church.

    Patients with chronic symptoms and evidence of chronic fecal stasis as indicated by an enlarged pouch, fecal impaction, or anal stenosis, were prescribed long-term antibiotic therapy. If there was improvement in symptoms after an initial two-week course, the dose was reduced to one tablet a day for at least three months.

    Among the 34 patients of which 18 were men with a mean age of 48.4 years, study findings included:

    • 31 had a J-pouch and 3 an S-pouch
    • 28 had a stapled and 6 a hand-sewn anastomosis
    • The most common presenting complaint was difficulty emptying the pouch (17 patients)
    • The most common diagnosis was anal stenosis (11 patients)
    • All patients with a stenosis had some improvement after dilation, and surgery restored pouch function

    Other presenting symptoms and their diagnoses included nocturnal fecal incontinence specific for anal stenosis and abdominal bloating, nausea, and cramping seen with afferent limb syndrome. Most patients had a specific cause for their symptoms, but many had multiple issues, including poor diet and poor defecation habits. Those with a poor diet ate too much fiber and produced stools that were solid or chunky. Poor defecation habits included spending very little time on the toilet and therefore needing to return multiple times to complete emptying of the pouch.

    This study is unusual, notes Dr. Church, in that it focused on patients who have symptoms indicating that their pouch was not emptying properly. “Few studies analyze pouch dysfunction in the context of the pathophysiology of the IPAA itself,” he says. “In other words, what symptoms would be expected from a pouch patient who eats a lot of fiber, who takes a lot of Imodium, who spends less than one minute on the toilet each time, or who goes to bed with a full pouch?”

    Most patients with symptoms of pouch dysfunction can be improved by therapy directed at the cause of the symptoms, says Dr. Church. These include:

    • Educating patients about pouch physiology to avoid food bolus blockages and minimize the effects of pouch twists and kinks
    • Use of Miralax to keep the stool consistency loose and avoidance of anti-diarrheals
    • Dilation of anal stenoses with steroid injection if there is scarring
    • Incision for narrow strictures and serial dilation for long strictures
    • Surgery for afferent limb syndrome
    • Biofeedback or Botox injection for pelvic floor paradox

    “In summary, an accurate diagnosis and effective treatment of pouch dysfunction is based on an appreciation of pouch physiology, correction of anatomic abnormalities that impair emptying, and management of stool consistency,” adds Dr. Church.

      Read More

      When pouches cannot empty: A cohort study of the symptoms this causes, the reasons it’s happening, and the treatments needed. Nugent E, Church JM. ANZ Journal of Surgery. 2022 Sep 21. [Online ahead of print]

      On What Makes a Good Surgeon: Insight from Surgeon and Mentor Dr. James Church

      For more information

      Dr. James Church
      Dr. James Church
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