Congenital Pouch ColonNNNNNNNNNNN (2).pptx

JJJ

1. Congenital Pouch Colon Presenter-Hadush T. (PSR) Moderator- Dr Woubedel ( Consultant Pediatric Surgeon ) September 15, 2021

2. Outline Introduction, Epidemiology & Embryogenesis Anatomy, Histology & Classification Clinical Features & Work-up Management & Outcome

3. Introduction An anomaly in which all or part of a shortened colon is replaced by a pouch-like dilatation, associated with ARM The pouch terminates in a fistulous communication with the genitourinary tract

4. Epidemiology Reported widely from the South Asian subcontinental countries India, Pakistan and Bangladesh with sporadic cases from other parts of the world 92.2% of reported cases are from India CPC comprises of around 5–15% of all cases of ARM in Northern India, 8–10% in Pakistan and 1.7% in Bangladesh More common in males than in females (3:1–7:1)

5. Etiology and Embryogenesis Theories Obstruction Vascular Faulty rotation & fixation Environmental Genetic

6. Anatomical Criteria CPC most commonly fits in the following criteria Presence of ARM Short total length of the colon The colon has a pouch of varying length and form with collected meconium/ faecal matter The pouch has an abnormal blood supply It has a uniformly thick and muscular colonic wall with hypertrophied mucosa The fistula with the genitourinary tract is large, muscular, and long. There is no transitional zone between the pouch colon and the normal bowel, bowel pattern changes suddenly and abruptly

7. Anatomy

8. Ana.. The anatomical features vary according to the length of the colon that exhibits pouching. In complete pouching of the colon, there is a large, dilated, thick-walled pouch occupying most of the left side of abdomen. The cecum, if present or the ileum opens the pouch from right side and there is associated malrotation In incomplete CPC, the cecum is situated in the epigastrium or the left hypochondrium and a variable length of normal colon is found, which ends in a large sac that communicates with the bladder in males and the vagina or vestibule in females. The pouch lacks haustrations, taeniae, and appendices epiploicae .

9. Ana.. The distal communication of the pouch is in most instances with genitourinary system. The fistula is usually quite broad and thick-walled, and measures up to 1 cm in external diameter. In males, the communication is most commonly present with the bladder and the fistula opens on the posterior wall of bladder near the base. In females, colocloacal fistula is the most commonly occurring fistula, followed by colovaginal and colovestibular fistulae. The pouch has a poorly developed mesentery and is supplied by the superior mesenteric artery on the superior and right side and an arcuate extension of the superior mesenteric artery on the left side. The inferior mesenteric artery is present only in incomplete CPC and supplies the lower half of left lateral side of pouch.

10. Ana.. The pelvic musculature is variable in cases of CPC, and when associated with a complete pouch or low vertebral anomalies, the pelvic and perineal muscles are poorly developed.

11. Histopathology Disorganization of the muscle coat in an arborizing manner Not clearly differentiated into inner circular and outer longitudinal muscles Circular muscle may be incomplete in 50% cases Mature ganglion cells in all cases with normal or occasionally hypertrophic nerve bundles(giant ganglia seen in 10%) Varying degrees of submucosal fibrosis, mucosal congestion and focal haemorrhages Heterotopic epithelium (gastric/pancreatic/small intestinal) may be present The pouch is an abnormally developed tissue and needs to be resected for better functional outcome of the remaining gut

12. Classification Complete: There is either none or little normal colon left that is insufficient for performing the pull-through Incomplete: The length of the normal colon is adequate enough to perform the pull-through without the need for doing a coloplasty

13. Associated Anomalies Mostly GU & GI

14. Clinical Presentation Males Absence of the anal opening Marked abdominal distension Fecaluria in nearly 50% Perforation with peritonitis and septicemia, fluid and electrolyte imbalance Females Absent anus & passage of meconium from an abnormal opening Gross abdominal distension Late presentation with moderate abdominal distension & poorly managed constipation Doughy abdomen due to retained feces Urinary incontinence

15. Work-up Neonatal CBC Electrolytes Plain abd film Single gas shadow or air-fluid level on the left side of the abdomen, occupying >50% of the abdominal width and terminating in a supralevator position Mimicking conditions ARM with hugely dilated rectosigmoid ARM with hydrometrocolpos ARM with a rectouterine fistula Localized pneumoperitoneu m

16. Work-up Before defnitive surgery Abdominal & spinal ultrasound Cystourethroscopy Distal colostogram Intravenous urogram and voiding cystourethrography Echocardiography

17. Management Neonatal management Preoperative Dehydration and electrolyte correction NGT decompression Temperature maintenance Bladder catheterization Antibiotic coverage Surgery Aim is to preserve the available length of colon for ensuring adequate absorption, faecal storage and continence postoperatively

18. Single Vs staged surgery Single stage Pouch excision / coloplasty with abdomino-PSARP Avoids the complications of diversion procedures, Cost effective Maximum potential for developing normal defecation reflexes Good or fair continence in 75% Unacceptably high risks of complications and mortality Staged surgery Diversion +/- pouch excision followed by abdomino-PSARP Currently practiced widely

19. Complete Pouch Tubularization of pouch till about 15 cm length is essential to preserve the function of the colon Fistula division, coloplasty, end colostomy and a proximal ileostomy followed by an abdominoperineal PT of the tubularized colon later is the preferred approach Alternately a window colostomy/proximal ileostomy can be done as an initial procedure depending upon the condition of the baby, technical skills of the surgeon and the available facilities

20. CP..

21. Coloplasty Reduce redundancy, improve peristalsis, and preserve colonic length Pouch mobilized completely by dividing the inferior mesenteric artery (if present) Pouch incised on the anti-mesenteric border, preserving the vascularity, and a tube is fashioned over a red rubber catheter to obtain a uniform calibre End colostomy/ primary pull through

22. Colo.. Advantages Preserves adequate length of colon for functional purposes (about 15 cm) Less faecal incontinence and diarrhoea later as compared to ileal pull-through Disadvantages Suture line leak Wound dehiscence Constipation Re-dilatation Increases operative time during initial surgery High mortality (30%–50%) if performed as a single staged procedure in neonates

23. Window colostomy An opening made in the anterior surface of the pouch.Fistula is not ligated. Advantages Simple procedure Minimum anaesthesia required Less operative time Can be done in a sick neonate Disadvantages Complications: massive pouch prolapse, bleeding from prolapsed pouch, pouch recession and stenosis Incomplete decompression requiring regular washouts Recurrent UTI and enterocolitis with Pouchitis Adhesive obstructions Failure to thrive & mortality rate of 15%–20%

24. Incomplete Pouch The preferred approach is fistula division, pouch excision and end colostomy followed later by abdominoperineal PT Other option is initial transverse colostomy followed by fistula division, pouch excision and abdominoperineal PT later at 6–18 months +/- protecting transverse colostomy

25. Definitive surgery Done after 6–18 months when the child has gained enough weight and has been evaluated completely for other associated anomalies The abdomino-PSARP/abdominoperineal pull-through (APPT)is performed with the child in supine lithotomy position In incomplete pouch, the end of the healthy colon is pulled down after abdominal ligation of fistula & mobilization In complete pouch, the tubularized colon is pulled down to create a neoanus by APPT Appendectomy should be performed at the time of pull-through A protective stoma (ileostomy/transverse colostomy) is preferred during a pull-through surgery. This could later be closed after 3–6 months.

26. Management in Girls Neonatal management- simple diversion is preferred Extensive surgeries for the vaginal component of the abnormality such as total urogenital mobilization are not required Division of the thick intervaginal septum and vagino-pouch remnant fistula can produce a single capacious cavity with a relatively normal/hypospadic urethral opening Management of urinary incontinence may need BNR / augmentation Monitoring for the obstetric implications of the associated genital anomalies

27. Follow-Up Initial follow-up examination is performed after 2 weeks and anal dilatation program started Then 3-monthly follow-up for the first year and 6-monthly follow-up for the next 3 years Thereafter the child can be followed up once in 2 years till adulthood The colon on follow-up examination shows normal calibre in most of the cases; however, dilatation of the tube coloplasty is rare but a serious problem

28. Outcome and Prognosis The mortality has decreased from 40% to 15% with the growing awareness and improved management of this disease Faecal continence Majority of incomplete PC has good continence 60% of complete PC have incontinence Urinary incontinence 80% girls have incontinence Growth and development Colonic re-dilatation

29. References

30. Thank you!!