Clinical and physiological evaluation of anorectal eversion during restorative proctocolectomy

Fifty patients had a restorative proctocolectomy with stapled end-to-end ileoanal anastomosis by the eversion technique. Median (interquartile range) maximum resting anal pressure was 90 (73-116) cmH(2)O before restorative proctocolectomy and 71 (51-88)cmH(2)O 1 year after surgery (P<0.001). Median maximum squeeze pressure was 141 (110-185)cmH(2)O before surgery and 146 (118-186) cmH(2)O 1 year after surgery (P not significant). Median thresholds for sensation in the lower third of the anal canal before and 1 year after surgery were 5.3 and 7.1 mA, respectively (P=0.006). One year after restorative proctocolectomy, all patients were continent, although two experienced leakage of mucus requiring a pad. Forty-two patients (84 per cent) could discriminate between faeces and flatus. Eversion of the anorectum during restorative proctocolectomy impairs the motor and sensory functions of the anal sphincter. Most patients achieved satisfactory anal continence, however, despite these physiological changes.