2025 Pediatric Surgery Update Course - Updates in Colorectal: Debunking Dogma

For vestibular fistula dilations, recommend only dilating to 7 Hegar to decrease potential scarring along the tract for future PSARP

Goal of fistula dilation is to maintain patency just large enough for soft, mustardy stool to pass through

Two studies in 2021 found no difference in wound complications, re-operations, or readmissions between early (less than 7-14 days) and delayed (6 weeks to 8 months) PSARP for vestibular fistulas

Wound breakdown and dehiscence was the most common complication in both neonatal and delayed PSARP groups, occurring in approximately 5-6% with no significant difference between groups

Fistula dilations represent controlled tears when starting from pinhole size, not true stretching

Perineal body-preserving PSARP showed no dehiscence, no prolapse, and only 13% required revision of anal stenosis at one-year follow-up in 2023 publication

Two-thirds of patients undergoing perineal body-preserving PSARP went home on postoperative day one

Perineal body-preserving PSARP is essentially the same technique used for bulbar fistula applied to vestibular fistula

Key technical principle for perineal body-preserving PSARP is to mobilize lateral planes and back wall thoroughly before coming around the anterior common plane

Perineal body-preserving PSARP can be converted to standard PSARP by extending the incision if visualization is inadequate

Perineal body-preserving PSARP does not add operative time compared to standard PSARP

Anal dilations are associated with parental anxiety, PTSD for both patients and caregivers, and post-traumatic stress symptoms in families

Preoperative dilations appear to be more tolerated than postoperative dilations

In Spanish study, children adequately sized at initial post-PSARP appointment did not receive dilations, while undersized children received dilations

Single institution review showed 2 children in each group (dilations vs no dilations) required re-operation for neoanal stricture, and approximately 15% required Heineke-Mikulicz stricturoplasty

PCPLC retrospective study of Hirschsprung disease found no difference in preoperative enterocolitis, postoperative enterocolitis, or fecal incontinence between neonatal pull-through (median 11 days) and delayed primary pull-through (median 98 days)

Families competent with irrigations will start treatment for enterocolitis before calling the surgeon

Patients with longer aganglionic segments who cannot be adequately decompressed at home may require earlier pull-through to prevent enterocolitis or perforation

Some data suggests possibly better continence in delayed Hirschsprung pull-through group, but studies have been underpowered

Multi-center retrospective study found 24% of Hirschsprung patients received at least one Botox injection

Cincinnati Children's prospective study (2020-2024, unpublished) found decreased risk of enterocolitis within 31 days after pull-through in patients receiving Botox (30% vs 50%)

Patients receiving Botox at time of pull-through had higher risk of diaper rash (60%)

Early work from Boston used per-kilogram Botox dosing up to maximum of 100 units

Ultrasound guidance for Botox injection allows visualization of needle placement, internal and external anal sphincter layers, superficial external anal sphincter, and sometimes puborectalis

Rate of concurrent Hirschsprung disease and anorectal malformation is approximately 2% based on Pena's series

Some papers show rate of concurrent Hirschsprung and ARM as high as 3-4%, while recent paper showed less than 1%

Single center study found ganglion cells in 90% of rectal fistula specimens taken during PSARP, with hypoganglionosis or absent ganglion cells in the rest

Absence of ganglion cells in fistula tissue does not necessarily mean Hirschsprung disease, as fistula tissue is not physiologic tissue

Patients with both Hirschsprung disease and anorectal malformation tend to have chromosomal anomalies, particularly trisomy 21