Operations for crohn's disease

Pre-op

• Anti-TNF agents (infliximab, adalimumab, certolizumab) - a/w increased operative complications - controversial
  • Ideally last dose >4/52 pre-op
  • UC - possible a/w pelvic sepsis after IPAA - 3-stage approach favoured in patients on anti-TNF drugs
  • CD - possible increase in complications, but controversial and not clear
  • Vedolizumab
    • Ideally last dose 4-8/52 pre-op
    • UC - no increased risk of infection
    • CD - similar rates of infection to anti-TNF drugs
  • Ustekinumab
    • Similar complication rates to anti-TNFs
    • Ideally last dose 4/52 pre-op
  • Restart 4/52 post-op where necessary
• Corticosteroids
  • Well-established detrimental effect on anastomotic healing
  • UC: should do delayed IPAA formation in patients who cannot be weaned to <20mg/day for 6/52 pre-op
  • CD - high risk of infection is generally ameliorated by stoma instead of primary anastomosis
    • Should still be reduced if possible
• Nutrition
  • UC - no pre-op TPN
  • CD - poorly studied in biologic era, but no clear role for pre-op TPN
    • Still need to optimise nutrition
• Planning
  • Pre-op imaging is crucial +/- capsule endoscopy
  • Looking for important disease in other areas of GIT
  • Planning extent of resection

Elective surgery

• Principles:
  • Attempt laparoscopy (safe in localised abscesses, simple intra-abdominal fistulas, perianastomotic recurrent disease, and disease limited to TI)
  • Control symptoms
  • Maintain function
  • Preserve bowel length
  • Margins: 2cm where bowel is grossly normal (palpate along mesenteric border to determine involvement)
  • Fistulae involving healthy, innocent, bystander segments of bowel should be treated with wedge resection rather than requiring two separate bowel excisions
• Faecal diversion if:
  • Adequate nutrition and minimal intra-abdominal sepsis - no diversion
  • Malnourished (albumin <20) and septic patients - diversion
  • Sabiston says peri-op biologic use is not a contra-indication to primary anastomosis
• Anastomosis: controversial but no clear preference for technique or configuration
  • End to end or side to side ok
  • Stapled or hand-sewn ok
  • Kono-S style has shown promise, under investigation currently
  • It seems to be safe, and may decrease risk of recurrence, but there is a low overall level of evidence (level IV as of June 2020)
• Internal bypass procedures - avoid wherever possible due to risk of malignancy
• Mesentery - treat with great care - prefer clamp with Kocher clamps then suture ligate rather than ligasure
• Small bowel disease - document length in every CD operation unless unsafe to do so. <200cm is high-risk for short bowel syndrome, while <100cm almost certainly require parenteral nutrition.

Stricturoplasty

• See 'Crohn Disease' section for indications and contraindications
• Procedure:
  • Start by examining the entire small bowel, and developing a 'roadmap'
  • Then can plan to deal with individual obstacles as they arise
• Short segment (<10cm):
  • Longitudinal antimesenteric incision from 2cm proximal to 2cm distal, then close transverse in one or two layers
• Fistulous tract:
• Size mismatch:
• Intermediate-segment (10-20cm): Finney-type or Jabouley
  • • Form U-shape
    • Longitudinal incision halfway between mesenteric and antimesenteric sides throughout the loop
    • Opposed edges are sutured together to form an isoperistaltic enteroenterostomy in two layers - basically a long side-to-side anastomosis
      • Interrupted seromuscular sutures to align back wall - outer posterior layer
      • Continuous full-thickness inner layer along back wall
      • Transition onto front wall around corner - either Connell or switch back to continuous over-and-over
      • Tie front wall in middle
      • Often unable to do a second layer front wall due to poor compliance of bowel
    • Shouldn't be done with strictures longer than 15cm (concerns for bacterial overgrowth)
• Long (>20cm): side-to-side isoperistaltic strictureplasty. Remember to biopsy site for malignancy.

• Colonic strictures are associated with very high recurrence (>50%) so segmental colectomy is not often the best option

Post-op

• A well-functioning stoma allows a much better quality of life than a poorly-functioning anorectum
  • Leakage
  • Skin irritation
  • Difficulty maintaining a seal
  • Retraction
  • Ischaemia
  • Mucocutaneous separation
  • Pyoderma gangrenosum can develop around stoma sites (2-5% of those who have stomas for IBD)
    • Early recognition and corticosteroid treatment
    • Good stoma care
• Ileostomy creation high-risk for readmission
  • AKI + dehydration common
• Infection - high-risk overall, particularly with immunosupression
  • Intra-abdominal sepsis reportedly 8%, median nine days post-op
  • High-risk: previous intestinal resection + triple therapy immunosuppressed (22% overall risk)
  • Anastomotic leaks: particularly those with multiple previous resections
    • Stapled side-to-side anastomosis have lower leak rates
• Stump blow-out
  • Oversewing staple line and decompressing rectal tube are purported to decrease blowout rate, but limited evidence
  • Can also bring above fascia to secure either below skin or as mucus fistula
• Pouch complications:
• VTE - more common than would be expected - consider 4 weeks prophylactic clexane
• ERAS is vital
• CD predictably recurs at or proximal to previous anastomosis, especially in smokers, patients with perforating disease, or patients who have had a prior resection
  • No risk factors = 3 months metronidazole
  • One or more risk factors = 3 months metronidazole + thioprine/TNF inhibitor
  • Colonoscopy should be done 6 months post-op