Terminal motor latency in the pudendal nerves after colectomy with mucosal proctectomy and ileal J pouch-anal anastomosis for ulcerative colitis

Pudendal Nerve Terminal Motor Latency in Patients With or Without Soiling 5 Years or more after Low Anterior Resection for Lower Rectal Cancer

BACKGROUND

To clarify the neurological function with respect to external anal sphincter (EAS) muscles in patients with or without soiling after low anterior resection (LAR) for lower rectal cancer, we examined the terminal motor latency in the pudendal motor nerves (PNTML).

MATERIALS AND METHODS

Thirty-eight patients after LAR for lower rectal cancer were studied electrophysiologically and compared with 30 healthy volunteers as controls (19 men and 11 women, aged 44 to 76 years of age, with a mean age of 65.5 years). Patients after LAR were divided into two groups [18 patients with soiling (12 men and 6 women, aged 51 to 77 years with a mean age of 64.8 years), 20 patients without soiling (13 men and 7 women, aged 47 to 75 years with a mean age of 62.1 years)]. The mean follow-up time from LAR was 67.2 months (range 60-84 months). Bilateral (left-sided and right-sided) PNTML tests were performed on all patients in order to measure the latency of the response in the bilateral EAS muscle following digitally directed transrectal pudendal nerve stimulation.

RESULTS

The distance from the anal verge to the level of anastomosis in patients with soiling (mean, 2.2 cm) was significantly shorter than that in patients without soiling (mean, 4.1 cm) (P < 0.05). Conduction delay of the bilateral PNTML in patients with soiling was longer than that in patients without soiling and normal subjects, significantly (P < 0.01, respectively). There was no significant difference between the right-sided and left-sided PNTML.

CONCLUSIONS

These findings support the hypothesis that soiling after LAR may be partially caused by damage to the bilateral pudendal motor nerves.

Relationship between gastrointestinal transit time and daily stool frequency in patients after Ileal J pouch-anal anastomosis for ulcerative colitis

BACKGROUND

To investigate how the gastrointestinal transit function changes after ileal J pouch-anal anastomosis (IPAA) for ulcerative colitis (UC) and to study whether gastrointestinal transit time (GTT) has an influence on daily stool frequency, we investigated the relationship between GTT and stool frequency per day.

METHODS

Forty patients with UC who had undergone restorative proctocolectomy, with ileostomy closure at least 48 to 120 months (mean 96.3) previously, and who had no preoperative and postoperative complications were recruited. They were divided into two groups on the basis of their stool frequency: 26 patients had a stool frequency of less than 6 times per day (group A: 16 men, 10 women; aged 15 to 59 years old, average 36.6) and 14 patients had a stool frequency of 7 or more times per day (group B: 10 men, 4 women; 24 to 56 years old, average 40.9). The GTTs using a radiopaque marker were studied. Interviews concerning the defecation states were performed at the examination.

RESULTS

High nocturnal stool frequency was significantly noted more in group B than in group A (P <0.001). All cases in group A and 12 cases in group B could discriminate flatus from feces, and there were significant differences between groups A and B (P <0.05). Feeling of stool remaining was significantly noted more in group B than in group A (P <0.01). Stool consistency in group A was harder than that in group B (P <0.001). Patients with soiling were significantly noted more in group B compared with those in group A (P <0.001). Incontinence was detected in only 2 cases in group B. Group A showed a better defecation state than group B. In the GTT study, the GTT was almost the same in groups A and B. The small bowel transit, pouch transit, and whole gut transit times in group B were faster than those of group A (P <0.001). Removal length of the terminal ileum in patients after IPAA: patients in group B (13.8 +/- 3.9 cm) had significantly more ileum removed compared with patients in group A (6.3 +/- 2.4 cm; P <0.001). Regression lines in the relationship between removal length of the terminal ileum and individual stool frequency showed there was a correlation between removal length of the terminal ileum and individual stool frequency per day in direct proportion (r = 0.79, P <0.001). A resection of more ileum, up to 15 cm, plays a role in increased stool frequency.

CONCLUSIONS

The present results suggested that rapid transit of both the small bowel and pouch may lead to a high stool frequency of 7 or more times per day with a poor defecation state after IPAA. It was also pointed out in this study that an important point is a resection of more ileum, up to 15 cm, plays a role in increased stool frequency.