Simple Anal Fistula: Clinical Criteria for Diagnosis and Local Anesthesia with Conscious Sedation for Surgery - An Observational Study

Introduction: to evaluate (i) acceptability of surgery for simple anal fistula under local anesthesia with conscious sedation by the patients and (ii) accuracy of a set of clinical criteria for diagnosing the condition. methods: simple anal fistula was diagnosed using a set of clinical criteria. the patients underwent surgery under local anesthesia with conscious sedation. intravenous paracetamol, diclofenac sodium, and midazolam were administered as adjuvants. fistulotomy with/without marsupialization was performed in most patients. clinical diagnosis was matched with operative findings. results: among 193 patients presenting with anal fistula, 61 were diagnosed as simple anal fistula and were scheduled for surgery under local anesthesia. one patient was found to have a complex anal fistula during intraoperative assessment and surgery was deferred. the operation was completed under local anesthesia with conscious sedation for 58/60 (96.7%) patients. acceptability of the procedure was assessed with the patients’ satisfaction score on a visual analog scale (vas) and their willingness to undergo fistula surgery under local anesthesia again if required. the median (interquartile range) vas score for patients’ satisfaction was 10 (9- 10). all patients expressed willingness to undergo fistula surgery under local anesthesia again if required. the clinical criteria were successful in diagnosing simple anal fistula in 58/61 (95.1%) patients. the remaining three patients had a high intersphincteric fistula (1) or a blind sinus (2). conclusions: acceptability of surgery for simple anal fistula under local anesthesia with conscious sedation was excellent. the proposed clinical criteria were highly accurate in diagnosing simple anal fistula.