Post-Anastomotic Enterocutaneous Fistulas: Associated Factors and Spontaneous Closure at a Tertiary Centre in Western Kenya

Abstract

Objective To determine the factors associated with the occurrence and spontaneous closure of enterocutaneous fistulas. Design A retrospective, hospital-based study of patients who developed enterocutaneous fistulas after resection and anastomosis. Setting The general and paediatric surgical wards of Moi Teaching and Referral Hospital (MTRH), a 550 bed tertiary teaching and referral hospital in the Western region of Kenya. Subjects Two hundred and twenty patients of all ages who underwent gut resection and anastomosis for varied reasons between 2002 and 2006. Main outcome measures The primary outcome measures were variables associated with development and spontaneous closure of fistulas while the secondary outcome measures were morbidity and mortality associated with enterocutaneous fistulas. Results Enterocutaneous fistulas formed in 22 of 220 patients and constituted 44% of all the complications after gut resection and anastomosis. Age younger than 20 years (p=0.04), female gender (p=0.032), duration of symptoms greater than one day prior to presentation to hospital (0.032), deranged electrolytes (p=0.042), delay in surgery after admission (p=0.043) and the use of ileal segment in the anastomosis (p=0.018) were significantly associated with occurrence of fistulas on univariate analysis. The use of ileal segment in the anastomosis (p=0.033), deranged electrolytes (p=0.045) and duration prior to surgery (p=0.045) were also found to be predictive of fistula formation on multivariate analysis. The spontaneous closure rate was 45.5%. Factors significantly associated with spontaneous closure were age greater than 20 years (p= 0.027) and occurrence of the fistula in an ileal segment (p=0.031). Enterocutaneous fistulas had a case specific mortality rate of 50%.The factor most significantly associated with mortality was re-operation (P<0.001) and this was also predictive of both mortality and prolonged hospital stay. Conclusion Renal dysfunction, delay before surgery and the use of ileal segments were significantly associated with the occurrence of enterocutaneous fistulas while age greater than 20 years and occurrence of fistulas in ileal segments had significant association with spontaneous closure of the fistulas. Re-operation is a strong predictor of mortality in interocutaneous fistula patients.