Evaluation of the effectiveness of using fine-pore foam in patients with unformed small intestinal fistulas: a retrospective observational study

Background . The treatment of unformed small intestinal fistulas is a severe pathology with no unified conservative approach, which necessitates the search for methods aimed at reducing fistula output and improving quality of life. Objective . To evaluate the effectiveness of fine-pore foam plugging in patients with unformed small intestinal fistulas. Materials and methods. A retrospective analysis of anonymized medical records of 19 patients with unformed small intestinal fistulas treated at the Yaroslavl State Medical University clinic between 1998 and 2022 was carried out. Inclusion criteria: daily fistula output ≥1 L, debilitating course, failure of conservative therapy. A plug made of fine-pore foam was placed in the fistula tract for 3-5 days. Outcomes assessed: reduction in fistula output (complete, partial, or none), fistula closure or maturation into a tubular / labiform fistula, and mortality. 95 % confidence intervals were calculated for proportions (Clopper-Pearson method). Results . The technique proved ineffective in 5 of 19 patients (26.3 %; 95 % CI 9.1-51.2 %). The remaining 14 patients (73.7 %; 95 % CI 48.8-90.9 %) had a marked decrease in fistula output. Complete fistula closure occurred in 6 patients (31.6 %; 95 % CI 12.6-56.6 %), and maturation into a tubular / labiform fistula followed by elective surgery in 4 patients (21.1 %; 95 % CI 6.1-45.6 %). Fistula output resumed in 4 patients (21.1 %; 95 % CI 6.1-45.6 %). Mortality was 4 / 19 (21.1 %; 95 % CI 6.1-45.6 %). In all patients with effective plugging, dressing frequency decreased from 4-6 to 1 per day, and enteral nutrition became possible. Conclusions . Plugging with fine-pore foam reduces daily fistula output in 74 % of patients with unformed small intestinal fistulas and helps to achieve fistula closure or reduced output in 53 %. The method can serve as a preparatory step for elective surgery, as well as an independent minimally invasive option for patients who have declined surgery.