Sacral nerve stimulation in patients with severe fecal incontinence after rectal resection

Abstract

Oncologic resection of rectal cancer has been reported to be associated with a significant rate of fecal incontinence (FI). The risk is greater in patients with a resection less than 6–8 cm from the anal verge [1]. Sacral nerve stimulation (SNS) has been advocated as a safe and effective therapy for severe FI and shown to be associated with minimal morbidity [2]. In patients with FI after anterior resection (AR), SNS is has been used in few cases, with varying results [1, 3]. Between 2006 and 2009, four patients (one male, three female), with severe FI following neoadjuvant therapy and AR performed for rectal cancer, were treated in our hospital with SNS. The median age was 65.5 years (range 49–73 years). All patients had undergone chemoradiation before the operation. Total mesorectal excision and longitudinal coloplasty had been performed during the operation in all patients. The mean distance of the anastomosis from the anorectal ring was 5 cm (range 2–8 cm). The median history of FI following AR was 26.5 months (range 25–28 months). None presented tumor recurrence, local or distant. The incontinence status was classified according to the Wexner score [4]. All patients were treated with conservative treatment, including drugs, constipating diet and biofeedback physiotherapy for 2 years. Before surgery, in all patients, anorectal manometry and endoanal ultrasonography were performed (Table 1). The percutaneous test stimulation was performed under general anesthesia. The response of S2–S4 was tested on both sides. If contraction of the anal sphincters could be obtained by SNS, percutaneous electrodes (Medtronic 3050; Medtronic, Minneapolis, MN, USA) were implanted. The patients were subsequently tested by SNS for a 4-week period. Patients who became candidates for permanent implantation based on an improvement of their continence received the permanent stimulation generator (INTERSTIM II, 3058; Medtronic, Minneapolis, MN, USA) under general anesthesia. Differences were analyzed by the Wilcoxon test for paired data. All patients tested had contraction of the anal sphincters during the SNS 4-week test period. All patients had least a 50 % reduction in episodes of incontinence and were given a permanently implanted system. The Wexner score fell from a median score of 15.5 before SNS to 5.5 during permanent stimulation (p \ 0.005). There were no significant differences in sphincter pressures measured by anal manometry. The patients with associated urinary incontinence presented improvement in their symptoms. There was no cessation of clinical response during the follow-up, and no complications were observed. After colorectal or coloanal anastomoses at a lower location, about 30–60 % of patients develop anal dysfunction due to the loss of the rectum and internal sphincter. These patients develop clinical symptoms and signs, such as anterior resection syndrome, which includes stool frequency, urgency, fragmentation and soiling. These symptoms usually disappear approximately 1 year postoperatively [5]. Our results of SNS in patients with FI after P. Moya A. Arroyo A. Frangi F. Candela Polo R. Calpena Rico Department of Surgery, University General Hospital of Elche, Alicante, Spain