Do you pack fistula sites with anything?

Management of Fistula Sites

No definitive recommendation can be made regarding the use of packing after drainage of an anorectal fistula or abscess, based on the available literature. 1

Current Practice and Evidence

• Common practice is to place an internal dressing (pack) into the cavity following incision and drainage of an anorectal abscess for hemostasis and to prevent premature closure of the skin 1
• Packing is traditionally changed regularly until the cavity heals 1
• Some clinicians alternatively place a catheter or drain into the abscess cavity, which drains into an external dressing and is left in place until drainage stops 1

Evidence Assessment

• Despite being commonly performed, the role of wound packing after anorectal abscess drainage remains unproven 1
• Proponents of packing suggest it may reduce healing time and decrease recurrence rates 1
• However, packing is associated with:
  • Increased pain during dressing changes 1
  • Higher healthcare expenses due to prolonged use 1

Research Findings

• A Cochrane review included only two studies (64 participants total) with high risk of bias, concluding that it's "unclear whether using internal dressings (packing) for the healing of perianal abscess cavities influences time to healing, wound pain, development of fistulae, abscess recurrence, or other outcomes" 1
• A multi-center observational study of 141 patients undergoing incision of primary anorectal abscess with subsequent packing found that packing is costly and painful without providing clear benefits to the healing process 1
• The most recent high-quality evidence comes from the PPAC2 randomized clinical trial (2022), which found that avoiding abscess cavity packing is less painful without increasing morbidity risk 2
  • 433 participants across 50 sites showed significantly lower pain scores in the non-packing group (28.2 vs 38.2, p<0.0001)
  • No significant difference in fistula formation (11% non-packing vs 15% packing, p=0.20)
  • No significant difference in abscess recurrence (6% non-packing vs 3% packing, p=0.20)

Management Approach for Fistulas

• For anorectal abscesses with an obvious fistula:
  • If the fistula is low and doesn't involve sphincter muscle (subcutaneous fistula), perform fistulotomy at the time of abscess drainage 1, 3
  • If the fistula involves any sphincter muscle, place a loose draining seton rather than performing immediate fistulotomy to prevent incontinence 1, 3
• Avoid probing to search for a fistula if one is not obvious, as this may cause iatrogenic complications 1, 3

Clinical Pitfalls and Considerations

• High recurrence rates after drainage (up to 44%) emphasize the need for complete and accurate drainage of the abscess 1
• Risk factors for recurrence include inadequate drainage, loculations, horseshoe-type abscess, and delayed time from disease onset to incision 1
• A third of perianal abscesses may develop a fistula-in-ano, increasing the risk of abscess recurrence requiring repeat surgical drainage 1
• For complex fistulas or those in immunocompromised patients, more specialized approaches may be needed 3

Based on the most recent and highest quality evidence from the PPAC2 trial, non-packing appears to be less painful without increasing complications, suggesting it may be the preferred approach for most patients with anorectal abscesses and fistulas 2.