Anal and neorectal function after ileal pouch-anal anastomosis

Determinants of optimal bowel function in ileal pouch-anal anastomosis - physiological differences contributing to pouch function

BACKGROUND

Variability in functional outcome after ileal-pouch anal anastomosis (IPAA) is to a large extent unexplained. The aim of this study was to perform multiple physiological and biochemical tests including an endoscopic examination with histology on IPAA patients with well and poorly functioning pouches to determine factors, or combinations thereof, contributing to functional outcome.

METHODS

All patients with ulcerative colitis undergoing restorative proctocolectomy between 2000 and 2013 (N = 108) were interviewed using a pouch functioning score. The best and worst functioning quartiles were invited to undergo examination with a barostat measuring pouch volume at preset variable distension pressures, and a pouch endoscopy.

RESULTS

Forty five of 58 eligible patients agreed to participate. The most significant physiological parameter differing between the well and poorly functioning pouches was pouch volume at first sensation, urge and discomfort (p value <.001). Urge volumes were 213 (CI 171-256) ml for poorly and 352 (CI 305-401) ml for well functioning pouches. Pouchitis episodes were negatively correlated to function. The poorly functioning patients had a higher prevalence of histological signs of inflammation and hand-sewn anastomosis, and a longer remaining rectal cuff, however, nonsignificant. The pouch pressure at sensation thresholds did not differ between the groups.

CONCLUSIONS

Pouch volume is the most dominant predictor of pouch function in this study. The present comprehensive study of a multitude of different factors that possibly could be contributing to functional outcome, failed to shed much further light on the functional variability among pouch patients. The pouch physiology remains to a large extent unexplained.

When Not to Pouch: Important Considerations for Patient Selection for Ileal Pouch-Anal Anastomosis

Ileal pouch-anal anastomosis (IPAA) is the preferred surgical treatment for patients who undergo colectomy and wish to avoid a permanent ileostomy. The overall outcomes are positive, with an improved quality of life and stable long-term pouch retention. However, certain conditions or disease states may be at a higher risk of pouch dysfunction or failure. For example, obese patients have an increased risk for postoperative complications. In addition, women with a history of obstetric complications and elderly patients with a history of sphincter damage or dysfunction may be at an increased risk for postoperative incontinence, although quality-of-life indices do not necessarily correlate with incontinence scores. Advanced age itself is not a contraindication to pouch surgery, and elderly patients can be considered for IPAA based on individual functionality and comorbidities. Pelvic radiation may lead to pouch dysfunction. Finally, patients with Crohn's disease and indeterminate colitis may have increased complications with IPAA, but highly specific patient selection leads to good rates of pouch retention. This article examines several clinical scenarios that require careful thought prior to considering IPAA.

Long-term function and manovolumetric characteristics after ileal pouch–anal anastomosis for ulcerative colitis

Background

Long-term pouch function and physiological characteristics after ileal pouch–anal anastomosis (IPAA) are poorly described. The aim of this study was to undertake a prospective investigation of long-term pouch function and manovolumetric characteristics.

Methods

Forty-two patients with a median follow-up of 16 years after IPAA were included. Function was assessed using a questionnaire and a score was calculated ranging from 0 to 15 (15 being the worst). Manovolumetry was performed and pouchitis recorded. A paired analysis was conducted, as the results were compared with previous data for each patient.

Results

The median functional score was 3·5 (range 0–10) at 2 years and 5 (range 1–11) at 16 years (P = 0·013). Resting anal canal pressures were higher (P &lt; 0·001) and squeeze pressures lower (P = 0·008) at long-term follow-up. Ileal pouch volumes at distension pressures of 10, 20 and 40 cmH2O were diminished at 16 years (P &lt; 0·001, P = 0·005 and P = 0·058 respectively). The volume and pressure for first sensation and urge to defaecate were reduced. Increased age correlated positively with a poor functional score. A history of pouchitis did not affect functional or physiological characteristics.

Conclusion

Ileal pouch function declines in the long term. The reasons are unclear, but the ageing process may have an impact.

Defecation mechanisms after proctocolectomy and ileal pouch--anal anastomosis in dogs

BACKGROUND AND AIMS

The role of intrinsic pouch motility after ileal pouch-anal anastomosis (IPAA) during defecation is still speculative.

MATERIALS AND METHODS

IPAA was performed in 12 dogs. Defecation mechanisms were evaluated by motility recordings during spontaneous defecation and during expulsion of an endoluminal balloon and by radiography with sequential sector-related gray scale analysis.

RESULTS

Spontaneous defecations appeared without significant changes in electrical or mechanical activity of the pouch. Sequential filling of the pouch led to defecation in only seven dogs while the others did not succeed in emptying their pouch even with maximal balloon inflation. Neither strain gauge measurements nor electromyography demonstrated peristaltic contractions of the pouch during defecation while sector-related gray scale analysis revealed strong contractions of the abdominal wall during pouch emptying.

CONCLUSION

Pouch emptying is independent of intrinsic pouch motility. The ileoanal pouch acts as a functionally passive reservoir, and its evacuation is initiated by a rise of the intra-abdominal pressure.

Scintigraphic comparison of neorectal emptying between colonic J-pouch anastomosis and straight anastomosis after stapled low anterior resection

BACKGROUND AND AIMS

Colonic J-pouch anastomosis after low anterior resection of the rectum has been reported to be associated with an increased risk of evacuation difficulty. Using scintigraphy we compared neorectal emptying after stapled low anterior resection between colonic J-pouch anastomosis and straight anastomosis.

PATIENTS AND METHODS

We studied 19 patients after colonic J-pouch anastomosis and 22 after straight anastomosis. After the introduction of an artificial stool containing (99m)Tc-DTPA into the neorectum sequential lateral gamma images were obtained. From the time activity curve of radioactivity in the whole pelvis the time taken to evacuate one-half of the introduced artificial stool ( t(1/2)) and the percentage of artificial stool evacuated in 1 min (Evac(1)) were calculated. Fourteen volunteers were also studied as the reference group.

RESULTS

The t(1/2) was significantly longer and Evac(1) significantly lower in patients after low anterior resection than in the reference group. t(1/2) was significantly longer in the pouch group than in the straight group. Anastomotic height was significantly correlated with both t(1/2) and Evac(1). Neither t(1/2) nor Evac(1) was correlated with the severity of impaired defecatory function.

CONCLUSION

Although neither of the two parameters of neorectal emptying was correlated with the severity of impaired defecatory function, less effective neorectal emptying in patients after colonic J-pouch anastomosis than in those after straight anastomosis may be a factor causing evacuation difficulty after colonic J-pouch anastomosis.

Key factors influencing bowel function after ileal W-pouch anal anastomosis: a spectral analysis of W-pouch motor activity

Restorative proctocolectomy with ileal pouch anal anastomosis (IPAA) has become the standard surgical procedure for ulcerative colitis (UC). The purpose of this study was to determine which factors are important to achieve good anal continence after IPAA in terms of the motor activity and pressure-volume relationship. A total of 17 patients with UC who underwent IPAA were evaluated. The internal ileal pouch pressure was transanally measured with and without volume-loading of the pouch which induces the urge to evacuate. The maximum tolerable volume (MTV), first urge volume (FUV), and ileal pouch compliance were calculated and the internal ileal pouch pressure records were subjected to spectral analysis for intensive evaluation of the intraluminal pressure waves. The FUV, correlation of the compliance of the FUV with MTV, and the remaining volume up to the MTV (RVMTV) were analyzed. Compliance of the FUV was significantly correlated with the RVMTV (r = 0.736, P < 0.01). The frequency of the phasic waves in the pouch decreased with length of follow up, reflecting improved function (r = -0.588, P < 0.05). The findings of this intensive analysis of manometric measurement indicate that the key factors in postoperative pouch function are RVMTV and the frequency of phasic waves in the W-pouch.

Myoelectric and motor activity after proctocolectomy and ileal pouch-anal anastomosis in dogs

BACKGROUND

The aim of this study was to investigate the motor function of the ileoanal pouch and to evaluate its coordination with proximal small-intestine motility.

METHODS

Proctocolectomy and ileal J pouch-anal anastomosis were performed in 12 dogs. Motility was recorded by serosal electrodes and strain gauge transducers.

RESULTS

Transmission of the migrating motor complex (MMC) on the pouch appeared in only 37 of 109 measurements. On the ascending limb there was a constant irregular activity with no MMC detectable. Motility pattern of the pouch did not change postprandially. Spontaneous defecation always appeared independently from MMC transmission without an increase of electrical or mechanical activity or endoluminal pouch pressure.

CONCLUSIONS

Ileal pouch motility is independent from motility patterns of the proximal intestine. Its random contractile activity might provide storage function and make the pouch act as a functional reservoir. Intrinsic pouch motility is not responsible for pouch evacuation under physiologic conditions.

Local regulation of postprandial motor responses in ileal pouches

BACKGROUND

Local mechanisms are involved in the postprandial regulation of ileal tone in healthy subjects, but whether these mechanisms affect the postprandial tonic response of ileal pouches has not yet been investigated.

AIMS

To study the effect of a meal on pouch tone and phasic motor activity in patients with gut continuity or ileostomy and, in the latter group, the effect of a pouch perfusion with chyme or saline.

PATIENTS

Twenty patients with ileal pouches: 10 with gut continuity and 10 with ileostomy.

METHODS

Pouch tone and the frequency of phasic volume events were recorded with a barostat under fasting and postprandial conditions and after perfusion of the isolated pouch with chyme or saline.

RESULTS

The meal increased pouch tone and the frequency of phasic volume events in the patients with gut continuity, but not in those with ileostomy. Pouch perfusion with chyme induced a greater increase in pouch tone than saline.

CONCLUSIONS

The meal stimulated pouch tone and phasic motor activity. These effects were at least partially related to local pouch stimulation by intraluminal contents.

Effects of loperamide on ileoanal pouch function

BACKGROUND

Opioid analogues are used to manage increased bowel frequency in patients with an ileoanal reservoir. The aim of the study was to determine the clinical efficacy of loperamide in patients with an ileoanal reservoir and to assess its effect on pouch motility.

METHODS

Fourteen patients with a pouch who had normal pouch emptying and anal function were studied. Ambulatory pouch and anal motility, and stool weights, were recorded for 24 h while taking no medication and for 24 h while receiving 8 mg loperamide. In a second analysis, patients were divided on the basis of bowel frequency into those with 4 or fewer motions (good function; n=6) and those with more than 6 per day (poor function; n=8), to determine any differential effects of loperamide.

RESULTS

Loperamide decreased median bowel frequency (no loperamide 5.5 versus loperamide 4.0, P=0.03) and 24-h stool weight (610 g versus 413 g, P=0.03) but not individual stool weights. Patients with poor function had both higher bowel frequency (8.0 versus 3.5 per 24 h, P=0.004) and higher stool weight (728 g versus 430 g, P=0.05) with no treatment than those with good function. High-amplitude pouch pressure waves were greater in number before defaecation in patients with poor function and did not decrease with loperamide, in contrast to patients with good function. Pouch baseline pressure decreased after defaecation to a similar extent in both groups and was not affected by loperamide.

CONCLUSION

Loperamide 8 mg per day reduces bowel frequency by reducing total stool weight, not individual stool weights. In patients with good function it also affects pouch motility. High bowel frequency is associated with increased pouch high-pressure waves.

The physiology of ileo-anal pouch function

Even excellent clinical function after ileo-anal pouch construction is associated with a variety of physiological abnormalities. Small bowel intestinal motility is essentially normal but the ileal reservoir serves to markedly suppress the ileal motor response both to progressive distension by intestinal contents and to transmitted myoelectrical complexes. As a result, the healthy pouch can accommodate a large volume of intestinal content before the rising baseline pressure and the appearance of large isolated contraction waves produce an urge to defecate. Evacuation in the normal pouch patient is rapid and highly efficient and is achieved by means of the Valsalva maneuver without any evidence of significant intestinal propulsion. External anal sphincter function is fully preserved but internal anal sphincter function is significantly impaired in the immediate postoperative period. Recovery occurs over the next 6 to 12 months but is often incomplete. Bacterial overgrowth in the pouch and prepouch ileum is almost universal and results in the premature deconjugation of primary bile salts and accumulation of secondary bile salts within the pouch. These produce morphologic changes in the ileal mucosa, and their excretion in pouch effluent gradually depletes the bile salt pool. Anerobic organisms also bind with vitamin B12 and the vitamin B12-intrinsic factor complex, resulting in subtle but measurable reductions in vitamin B12 levels in pouch patients. Finally, anerobic fermentation of mucus and undigested carbohydrate results in excessive quantities of short chain fatty acids within the pouch lumen. The clinical significance of these substances is unclear, but they may have an adverse action on both ileal mucosal and smooth muscle function. In essence, however, the pouch surgeon can maximize the likelihood of good clinical function by constructing a large capacity pouch, by avoiding surgery in patients with clearly deficient anal sphincter mechanisms, and by careful attention to pouch-anal anastomotic technique.

Internal anal sphincter: advances and insights

The internal anal sphincter, the smooth muscle component of the anal sphincter complex, has an ambiguous role in maintaining anal continence. Despite its significant contribution to resting anal canal pressures, even total division of the internal anal sphincter in surgery for anal fistulas may fail to compromise continence in otherwise healthy subjects. However, recently reported abnormalities of the innervation and reflex response of the internal anal sphincter in patients with fecal incontinence indicate its significance in maintaining continence. The advent of sphincter-saving surgery and restorative proctocolectomy has re-emphasized the major contribution of the internal anal sphincter to resting pressure and its significance in preventing fecal leakage. The variable effect of rectal excision on rectoanal inhibitory reflex has led to a reappraisal of the significance of this reflex in discrimination of rectal contents and its impact on anal continence. Electromyographic, manometric, and ultrasonographic evaluation of the internal anal sphincter has provided new insights into its pathophysiology. This article reviews advances in our understanding of internal anal sphincter physiology in health and disease.

Physiologic evaluation and surgical management of failed ileoanal pouch

BACKGROUND

Following proctocolectomy and ileal pouch-anal anastomosis, a small percentage of patients will have poor functional results attributable to pouchitis or anastomotic or septic complications. Additionally, functional failures can occur secondary to limited pouch capacity and compliance. We present five such patients managed with operative conversion to W-ileal pouch-anal anastomosis and examined physiologic parameters important for improving functional results.

METHODS

Five female patients (mean age, 30 (range, 24-39) years) with poorly functioning J-ileal pouch-anal anastomoses were referred for evaluation with symptoms of high stool frequency and incontinence problems. Three had severe nocturnal incontinence, and the remaining two patients experienced minor nocturnal incontinence. Preoperative and postoperative evaluation included barium pouch studies, flexible sigmoidoscopy, anal manometry, evacuation volume, and pouch compliance. Pouch-to-anal pressure gradients were calculated. To improve reservoir capacity and compliance, all five patients underwent conversion to W-ileal pouch-anal anastomoses.

RESULTS

Twenty-four hour and nocturnal stool frequencies decreased from 13.8+/-1.7 and 3+/-1.3 to 5.8+/-0.3 and 0.3+/-0.2 postconversion (P < 0.05). Mean pouch evacuation volume increased from 83+/-27 to 290+/-29 ml postoperatively (P < 0.05). Pouch compliance increased from 2.7+/-0.5 mmHg/ml to 7.7+/-0.6 mmHg/ml postconversion (P < 0.05). Improvement in postconversion stool frequency correlated with an increase in pouch evacuation volume (r=-0.87). All patients reported improved day and nocturnal continence, despite no significant change between preoperative and postoperative anal manometric pressures. Improved continence correlated with a significant widening of the pouch-to-anal pressure gradients, which increased from 5 to 25 mmHg at 150 ml following pouch conversion.

CONCLUSIONS

Poorly functioning ileal reservoirs secondary to limited capacity and compliance can be successfully managed with conversion to W-ileal pouch-anal anastomosis. The increased pouch capacity is associated with improvement in compliance and widening of the pouch-to-anal pressure gradients, providing excellent functional results.

Long-term functional evaluation of straight coloanal anastomosis and colonic J-pouch: is the functional superiority of colonic J-pouch sustained?

AIM

This study was designed to analyze the functional and clinical outcomes of straight coloanal anastomosis compared with colonic J-pouch performed after low anterior resection.

MATERIALS AND METHODS

Between September 1989 and June 1996, all patients who underwent low anterior resection with anastomosis less than 4 cm from the dentate line were classified into two groups based on the restoration of intestinal continuity: "straight" coloanal anastomosis (n = 39) or colonic J-pouch (n = 44). Both groups were assessed according to the level of anastomosis, anastomotic complications (stricture, leak, pelvic abscess), age, and gender. For comparison of functional outcome, daily bowel movements, tenesmus, urgency, incontinence score (range, 0-20), and anorectal manometric findings were evaluated preoperatively and at six months, and one and two years after surgery.

RESULTS

There were no significant differences between the groups relative to age: (coloanal anastomosis, 66.3 +/- 10.1 (range, 46-86), vs. colonic J-pouch, 64.9 +/- 13.2 (range, 39-88) years); gender (females): (coloanal anastomosis, 46.2 percent vs. colonic J-pouch; 38.6 percent); diagnosis: (rectal carcinoma: coloanal anastomosis, 84.6 percent, vs. colonic J-pouch, 77.3 percent); preoperative incontinence score (coloanal anastomosis, 1.5 +/- 4.6, vs. colonic J-pouch, 1.1 +/- 4); bowel movements: (coloanal anastomosis, 2.1 +/- 2.3, vs. colonic J-pouch, 2.1 +/- 1.9/day); level of anastomosis: (coloanal anastomosis, 1.8 +/- 1.3, vs. colonic J-pouch, 1.5 +/- 1.3 cm from the dentate line); history of perioperative radiation therapy: (coloanal anastomosis, 15.4 percent, vs. colonic J-pouch, 20.5 percent); or manometric findings. There was also no significant difference in postoperative mortality: (coloanal anastomosis, 5.1 percent, vs. colonic J-pouch, 2.3 percent); or anastomotic complications: (coloanal anastomosis, 7/39 (17.9 percent), vs. colonic J-pouch, 2/44 (4.5 percent) P = 0.08); strictures: (10.3 vs. 0 percent); leaks: (5.1 vs. 2.3 percent); bleeding: (2.6 vs. 0 percent); rectovaginal fistula: (0 vs. 2.3 percent). Also, in the colonic J-pouch group, two patients developed pouchitis, and one patient experienced difficult evacuation one year after surgery. There was a statistically significant better function judged by less frequent bowel movements (4 +/- 2 vs. 2.4 +/- 1.3/day; P < 0.005) and urgency (36.7 vs. 7.7 percent; P < 0.05), incontinence score (2.2 +/- 3.7 vs. 0.8 +/- 1.6; P < 0.05) up to one year after surgery. At two years, the coloanal anastomosis group did not show statistical improvement in functional results compared with one year postoperatively. Rectal compliance in manometric findings was significantly increased in the coloanal anastomosis group at one year after surgery (12.4 +/- 12.6 vs. 4.2 +/- 1.5 ml/mmHg; P < 0.05). However, these differences were less profound after two years.

CONCLUSION

The functional superiority of the colonic J-pouch was greatest at one year after surgery. By two years, adaptation of the "straight" coloanal anastomosis yielded similar functional results. However, the almost fourfold reduction in anastomotic complications in the colonic J-pouch group reveals a second potential advantage of this technique.

Proctocolectomy with jejunal pouch-distal rectal anastomosis: an alternative to ileal pouch reconstruction

The aim of this study was to determine whether a jejunal pouch would have a lower resting pressure, be more distensible, and have more interdigestive migrating myoelectric complexes and less fecal bacterial overgrowth than would an ileal pouch after proctocolectomy and pouch-distal rectal anastomosis. In six conscious dogs with a jejunal pouch-distal rectal anastomosis and six with an ileal pouch-distal rectal anastomosis (controls), pouch distensibility and motility were measured using a barostat and perfused pressure-sensitive catheters passed per anum, pouch electrical activity was recorded using chronically implanted electrodes, and the number of bacteria per gram of stool was assessed by culture. Dogs with a jejunal pouch had lower resting pouch pressures, more distensible pouches, faster frequencies of pacesetter potentials in the pouch, more phase 3 intervals of the interdigesive migrating myoelectric complex reaching the pouch, but similar numbers and types of bacteria in their stools compared to the dogs with an ileal pouch. We concluded that jejunal pouches have a lower resting pressure, are more distensible, have more cleansing contractions, but a similar fecal flora compared to ileal pouches. A jejunal pouch has features that make it an attractive alternative to an ileal pouch for pouch-distal rectal or pouch-anal canal anastomosis after proctocolectomy.

Is age relevant to functional outcome after restorative proctocolectomy for ulcerative colitis?: prospective assessment of 122 cases

OBJECTIVE

Restorative proctocolectomy for mucosal ulcerative colitis is well established. However, the effect of age on physiologic sphincter parameters is poorly understood. Our objective was to determine whether age at the time of restorative proctocolectomy correlates with physiologic changes.

SUMMARY BACKGROUND DATA

In the approximately 20 years during which restorative proctocolectomy has been performed for ulcerative colitis, the indications have changed. Initially, the procedure was recommended only in patients under approximately 50 years. However, the procedure has been considered in older patients because of the increasing age of our population, the increasing frequency of recognition of patients during the "second peak" of mucosal ulcerative colitis, and the decreasing morbidity rates, due to the learning curve and to newer techniques, such as double-stapling. Few authors have presented data analyzing the effects of this operation in older patients.

METHODS

One hundred twenty-two patients who had undergone a two-stage restorative proctocolectomy for mucosal ulcerative colitis were divided into three groups according to age: group I (>60 years), 11 men, 6 women; group II (40-60 years), 29 men, 18 women; and group III (<40 years) 29 men, 29 women. The patients were prospectively evaluated using anal manometry and subjective functional results. Comparisons were made before surgery, after colectomy and before closure of ileostomy, and at 1 or more years after surgery.

RESULTS

There were no significant differences among the groups relative to manometric results, frequency of bowel movements, incontinence scores, or overall patient satisfaction. The postoperative mean and maximum resting pressures were significantly reduced (p < 0.001), and conversely the sensory threshold (p < 0.005) and capacity (p < 0.001) were increased in all groups up to 1 year after surgery. There were no statistically significant changes in the squeeze pressure or length of the high-pressure zone in any group at any point in time. After surgery, the mean and maximum resting pressures had returned to 80% of their original values.

CONCLUSION

Although anorectal function is transiently somewhat impaired after restorative proctocolectomy, the impairment is not an age-related phenomenon.

Ileocecal reservoir reconstruction with physiologic function after total mesorectal cancer excision

BACKGROUND/AIMS

After proctectomy for low rectal cancer and straight coloanal reconstruction, the main causes for increased daily stool frequency, urgency, and incontinence are the limited capacity and distensibility of the anastomosed colic segment in the pelvis. The authors postulated that a pedunculated (preserving the nerve) ileocecal interpositional graft (cecum-reservoir) placed between the sigmoid colon and the anal canal would greatly reduce these inconveniences.

METHODS

The authors evaluated the safety, defecation quality, and anorectal physiology of such a neorectum in 20 consecutive patients with rectal carcinoma between 5 and 10 cm above the anal verge who underwent total mesorectal excision.

RESULTS

No perioperative morbidity related to the technique and no mortality was observed in these 20 patients. Six months after the operation, 16 patients showed excellent and 4 patients good defecation quality, with maximal tolerable volumes, compliance, and mean colonic transit times comparable to age- and gender-matched healthy volunteers. In addition, anal resting pressure was decreased, squeeze pressure was maintained, and the rectoanal inhibitory reflex remained positive in 80%.

CONCLUSIONS

The cecum-reservoir as a neorectum, using an intact neurovascular colonic segment, is a safe technique, providing excellent defecation quality. It enables a nearly normal physiologic anorectal function, which is already seen 6 months postoperatively.

Electrophysiologic assessments in pudendal and sacral motor nerves after ileal J-pouch-anal anastomosis for patients with ulcerative colitis and adenomatosis coli

PURPOSE

To clarify neurologic function with respect to external anal sphincter and puborectalis muscles after J configuration ileal J-pouch-anal anastomosis for patients with ulcerative colitis and adenomatosis coli, we examined the terminal motor latency in the pudendal and sacral motor nerve (S2-4).

METHODS

Latency of the response in the external anal sphincter muscle following digitally directed transrectal pudendal nerve stimulation (PNTML) and in the puborectalis muscle following transcutaneous magnetic stimulation of the cauda equina at the levels S2-4 (SMNLTSS) were measured in 12 patients with ileal J-pouch-anal anastomosis; they were divided into a group with continence (7 cases) and a group with soiling (5 cases). Results were compared with data obtained from 12 patients before operation and 15 controls.

RESULTS

Conduction delay of PNTML and SMNLTSS in patients with soiling was longest, followed by delay in those without any soiling, then delay in patients before operation, and then controls. In addition, significant differences were also noted between conduction delay of PNTML in controls and those who are incontinent and experience soiling (P < 0.05 and P < 0.01, respectively), and there were significant differences also noted between conduction delay of PNTML in patients before operation and those who are incontinent and experiencing soiling (P < 0.05 and P < 0.01, respectively). Conduction delay of PNTML and SMNLTSS were found in patients before operation rather than in controls. No significant differences were noted between conduction delay of PNTML and SMNLTSS in patients before operation and controls. Significant differences were also noted between conduction delay of PNTML and SMNLTSS in patients who are incontinent and experiencing soiling (P < 0.01, respectively).

CONCLUSION

These findings support the hypothesis that soiling after this procedure may be partially caused by damage to pudendal and sacral motor nerves (S2-4).

Salvage surgery for ileal pouch outlet obstruction

Sixteen patients with ileal pouch outlet mechanical obstruction had major abdominal revision of the ileoanal anastomosis. Before operation all had severe difficulty in evacuation which required catheterization in 11. Eleven patients had a long efferent limb and/or long anorectal cuff, and five had a persistent stricture at the ileoanal anastomosis. None had pouchitis. The pouch was fully mobilized abdominally and the obstructing lesion resected. A new handsewn ileoanal anastomosis was formed. In two cases pouch volume was increased by incorporating an additional loop of ileum. All anastomoses but one were covered by a loop ileostomy. There were no deaths. Major complications occurred in two patients. Function was assessed in 15 patients; in one the ileostomy had not been closed. Median (interquartile range) frequency of defaecation per 24 h fell from 15 (7.3-19.5) to 6 (4.5-6.0) (P = 0.0033). Of the 11 patients who required a catheter before operation six evacuated spontaneously, three were improved but intubated on some occasions and two were unchanged after revisional surgery. Of the ten incontinent patients, five became continent, four were improved and one remained unchanged. There was a new continence disturbance in four (minor nocturnal in three) of the remaining five patients. One patient underwent further abdominal salvage surgery and another required establishment of an ileostomy because of poor function. Combined abdominoanal salvage surgery for outlet mechanical obstruction was successful in averting an ileostomy in 13 of 16 patients, and significantly improved pouch function in 12 of 15.

Simple radiographic evaluation of ileoanal pouch volume

PURPOSE

Total colectomy and mucosal protectomy with ileal reservoir and anal pull-through is used in the treatment of ulcerative colitis or familial polyposis, with one complication being frequent bowel movements. A simple radiographic test to predict frequency of bowel movements and measure spasticity was evaluated.

METHODS

Fourteen patients underwent evaluation after ileal reservoir and anal pull-through J-pouch construction. Barium sulfate suspension was instilled into the pouch via the anus in the standing position until reflux flowed into the small intestine proximal to the pouch and patients felt the urge to defecate. Total volume infused (VOLtot), volume to reflux (VOLrflx), and volume voided (VOLvoid) were measured.

RESULTS

VOLvoid and the "voiding efficiency" (VOLvoid/VOLtot) correlated significantly with stool frequency (R=-0.744, P<0.002 and R=-0.754, P<0.002, respectively). Time from operation was correlated with VOLvoid and stool frequency (R=-0.723, P<0.003 and RO.573, P<0.032, respectively).

CONCLUSIONS

The addition of quantitative measurements to this radiographic test gives useful information about pouch performance. Furthermore, the data imply that spasticity, as measured by voiding quantum and efficiency, rather than actual pouch volume is a major determinant of bowel movement frequency.

Electrically stimulated colonic reservoir for total anorectal reconstruction

Total anorectal reconstruction after abdominoperineal excision of the rectum has failed to achieve perfect continence. Electrically stimulated reservoir evacuation in combination with an electrically stimulated gracilis neoanal sphincter might improve results. A J pouch was constructed in an isolated colonic loop of seven dogs. Bipolar square wave pulses were delivered via two intramural stainless steel electrode pairs at 10 Hz. Stimulation parameters were varied to achieve adequate contraction. Serosal strain gauges recorded spontaneous and stimulated pouch motility. Evacuation was quantified by a volume displacement technique and observed fluoroscopically. Recordings were performed for a median of 3 (range 1-11) months. At 10 Hz and 0.5 ms pulse width, stimulation was required for 2 min and at voltages of 15 V (n = 4), 18 V (n = 1) and 20 V (n = 2) to obtain a contraction of amplitude comparable to that of a spontaneous contraction. Suprathreshold stimulation invariably resulted in colonic pouch contraction. The mean(95 per cent confidence interval (c.i.)) stimulus-response latency was 25.5(1.9) s. The mean(95 per cent c.i.) intraluminal pressure generated during stimulation was 114.1(17.0) cmH2O and 64.6(12.0) cmH2O during spontaneous activity (P < 0.001). In conclusion, electrical stimulation via intramural electrodes produced contraction generating sufficient intraluminal pressure to effect evacuation of a canine colonic pouch. This has potential for incorporation with an electrically stimulated neoanal sphincter in total anorectal reconstruction to improve evacuation and continence.

Gradient of pressure and time between proximal anal canal and high-pressure zone during internal anal sphincter relaxation. Its role in the fecal continence mechanism

PURPOSE

The normal response to rectal distention is a relaxation of the proximal anal canal (PAC). We hypothesized that this mechanism would require a gradient of pressure and time to preserve continence.

METHODS

Sixteen volunteers (10 male), mean age, 41.5 (range, 24-60) years, were studied using an eight port axial catheter with a compliant balloon at its tip. Relaxation was induced by a small volume of rectal distention (15-30 ml of air) and was recorded until recovery of resting anal pressure (RAP). Duration of relaxation was measured until recovery of RAP. Amplitude of relaxation was determined between RAP before rectal distention (RAP-BR) and pressure at the point of maximum relaxation (RAP-PMR). Gradient of pressure was determined by comparing RAP-PMR in the high-pressure zone (HPZ) and PAC. Contraction in the distal anal canal was interpreted as external anal sphincter contraction (EASC) and was compared with RAP-PMR in the HPZ.

RESULTS

Relaxation was significantly greater in PAC than in HPZ (50 vs. 36 percent; P = 0.001). RAP-PMR was significantly higher in HPZ than in PAC (30.7 vs. 12.6 mmHg; P = 0.001). EASC was observed in six patients and did not show significant difference with RAP-PMR in HPZ (39.7 vs. 36.3 mmHg; not significant). Relaxation began at the same time in all levels but lasted significantly longer in PAC compared with HPZ (13.5 vs. 9.4 sec; P = 0.003).

CONCLUSION

Anal relaxation induced by small volume rectal distention involves a gradient in the pressure and time of relaxation between PAC and the HPZ.

Physiology of ileal pouch-anal anastomosis. Current concepts

PURPOSE

Increasing experience with ileal pouch-anal anastomosis (IPAA) associated with increasing knowledge about anorectal physiology has lead to a large number of publications. The purpose of this review is to evaluate the current understanding of fecal continence as revealed by the evolution of the ileoanal procedure.

METHODS

Review of the literature covering the most important physiologic parameters involved in fecal continence was undertaken.

RESULTS

Rectoanal inhibitory reflex is probably absent after IPAA but is preserved when distal anorectal mucosa is spared. Anal resting pressure decreases but is less affected when the internal anal sphincter is less traumatized. Squeeze pressure is not importantly affected, and the importance of reservoir function as a determinant of stool frequency is emphasized. IPAA does not affect the coordination between pouch and anal canal motility in the majority of cases. Normal continence is preserved, even during the night, by preserving a gradient of pressure between the pouch and anal canal.

CONCLUSIONS

Physiologic concepts are well established, but controversies about the continence mechanism related to IPAA remain. The IPAA procedure has allowed discrimination of details about the function of multiple structures involved in fecal continence.

The use of an ileostomy connector to diminish the frequency of defecation prior to ileostomy closure in patients with a pelvic pouch

A new method for allowing stool passage into the pelvic pouch before ileostomy closure to verify the defecation state and diminish stool frequency is reported herein. This was accomplished by fitting an ileostomy connector connecting the proximal and distal openings of the diverting loop stoma. The ileostomy connector was initially in place for 6 h a day, the length of time being gradually increased until it was able to be left in for 24 h a day over a 3-month period. The calculated daily frequency of stools decreased from 24 to 6 or 7 times, and the mean daily frequency immediately after ileostomy closure was 6.5 times. Physiological study also showed an improvement, with squeeze pressure increasing from 35 cmH2O to 116 cmH2O and the maximum tolerated volume increasing from 35 ml before, to 90 ml 3 months following the use of an ileostomy connector. Thus, we conclude that an ileostomy connector may be useful to predict postoperative functional outcome and its complications, and to diminish the frequency of defecation before ileostomy closure in patients with a covering loop stoma.

Endosonography of the anal sphincter after ileal pouch-anal anastomosis. Relation with anal manometry and fecal continence

PURPOSE

The aim of the present study was to visualize supposed defects of the internal anal sphincter after ileal pouch-anal anastomosis (IPAA) by anal endosonography and to relate these findings with anal manometry and fecal continence.

METHODS

We investigated 23 patients, visualized the sphincter complex by anal endosonography, and quantified the anatomic changes of the sphincter. Anal resting and squeezing pressures as well as length of the anal canal were determined by anal manometry. Continence was objectively scored by an observer not involved in treatment of patients and subjectively by patients themselves.

RESULTS

At anal endosonography, the mean thickness of the internal anal sphincter was 1.16 mm (95 percent confidence interval, 0.98-1.33), which is significantly less than in normal volunteers. Tapering of the internal anal sphincter only occurred in six patients (of whom two had a gap in the internal sphincter). In 17 patients endosonography showed a thin internal anal sphincter without essential variation in thickness over the complete circumference. Approximately eight weeks after ileostomy closure following IPAA, maximum resting pressure (MRP) and length of the anal canal appeared to be significantly decreased compared with values before IPAA (P = 0.001 and 0.002, respectively). These differences were less striking (P = 0.05 and 0.04, respectively) when measured six or more months after ileostomy closure. The extent of reduction of the MRP and thickness of the internal anal sphincter were not correlated with grade of continence or with subjectively scored continence.

CONCLUSIONS

IPAA leads to a reduction of thickness of the internal anal sphincter and reduction of the MRP. Tapering or gaps in the internal anal sphincter are probably caused by direct trauma to this sphincter because of mucosectomy, whereas in cases of circular reduction of thickness of the internal anal sphincter without tapering or gaps, direct trauma is an unlikely explanation; this reduction is probably caused by denervation. IPAA compromises continence to a variable degree in 18 of 23 patients. No correlations were found between the extent of reduction of the MRP and the extent of reduction in internal anal sphincter thickness or between these two parameters and objectively or subjectively scored continence. Difficulties in obtaining reliable information on continence may be a causal factor. A striking discrepancy was noticed among objective, scored disturbances in continence, and overall satisfaction concerning level of continence by patients themselves.

Fecal incontinence

Fecal incontinence is a common but infrequently reported, imperfectly understood, multifactorial disease with far-reaching socioeconomic and psychological implications. Limited success with somewhat empirical surgical procedures implies that patients should be investigated fully, indications for surgery should be clear, and disability should be serious enough to demand surgical intervention. Dietary adjustments and medical treatment should be tried first. Unwelcome though it is, colostomy may be the ultimate remedy in some patients.

Ileal pouch pressures after defecation in continent and incontinent patients

After ileal pouch-anal anastomosis, a pouch/anal canal pressure gradient is present such that mean pressures in the anal canal exceed pressures in the pouch facilitating fecal continence. Such a relationship was not present in incontinent patients.

PURPOSE

Our aim was to evaluate characteristics of pouch pressures dynamically in continent and incontinent patients following ileal pouch-anal anastomosis (IPAA).

METHODS

A multichannel microtransducer catheter was positioned in eight continent patients and nine incontinent patients after IPAA. Twenty-four-hour recordings of pouch pressures and large pressure wave contractions were recorded when patients were awake, asleep, and after evacuation.

RESULTS

When patients were awake, pouch pressures were similar. However, nocturnal pouch pressures were higher in the incontinent group (P < 0.05). Large pressure wave amplitude was higher in incontinent patients when awake and asleep (P < 0.05). Moreover, pouch pressures failed to decline in the incontinent group after evacuation, unlike continent patients.

CONCLUSION

Compared with continent patients, incontinent patients after IPAA had persistently high phasic and basal pouch pressures at night and following pouch evacuation.

Does the level of stapled ileoanal anastomosis influence physiologic and functional outcome?

PURPOSE

The aim of this investigation was to ascertain how the length of anal canal preserved above the dentate line in stapled end-to-end ileoanal anastomosis influenced late outcome.

METHODS

Two groups, high cuff group and low cuff group of nine subjects with stapled anastomosis, matched for sex, age, pouch configuration, and mean follow-up, representing the highest (median, 2.5 cm) and lowest (median, 0.7 cm) anal cuff lengths in our series, were selected. Physiologic and functional parameters were appraised preoperatively, at the time of ileostomy closure, and at 1, 3, 6, and 12 months after reestablishment of intestinal continuity.

RESULTS

At one year, the drop in mean anal canal resting pressure was 13 percent in the high cuff group (not significant) and 31 percent in the low cuff group (P < 0.05); mean maximum squeezing pressure did not differ significantly from preoperative values in both groups. The mean volume of the ileal pouch was higher in the low cuff group at all insufflation pressures. The rectoanal inhibition reflex reappeared in four high cuff group patients and in none of the low cuff group patients. Mean distention pressure (cm H2O) and volume (ml) eliciting urge sensation were 80 and 360 in the low cuff group compared with 40 and 240 in the high cuff group (P < or = 0.05). Daytime bowel movements and night incontinence were significantly better in the low cuff group. No statistical differences were observed for night stool frequency, daytime incontinence, pad use (day and night), discrimination between gas and feces, ability to defer evacuation, and difficulty in emptying the pouch.

CONCLUSION

Patients with stapled anastomoses and a low rectal cuff length, despite presenting lower anal resting pressure and absence of rectoanal inhibition reflex, had a better functional outcome in terms of continence than those with a high cuff length.

Ambulatory pouch and anal motility in patients with ileo-anal reservoirs

Twelve patients were studied for a median of 18 hours (range 8.5-21.5 hr) by continuous, ambulatory, simultaneous pouch and anal manometry 10-85 months after restorative proctocolectomy. Two main patterns of motility were observed: (1) Large isolated contractions up to 68 cm H2O in amplitude and up to 67 seconds in duration were present in ten patients. These were often associated with the urge to defaecate and were more frequent before defaecation than after but did not appear to be associated with expulsion of faeces from the pouch. In two patients atypical large isolated contractions up to 378 cm H2O in amplitude were observed. (2) Rhythmic contractions at a frequency of 7-11 per minute and amplitude of 24-330 cm H2O, occurred for a duration of 18 seconds to 18 minutes in six patients. In the other six patients this motility pattern was not seen. Of the 12 patients nine were considered to have good function (five or less bowel actions per 24 hours) and three poor function (ten or more bowel actions per 24 hours). Rhythmic activity was the predominant motility pattern in all three with poor function whereas large isolated contractions predominated in those with good function, although there was considerable overlap in the types of motility observed between patients with good and poor function. Mean pouch pressure tended to be higher in patients with poor function than in those with good function both throughout the entire recording and during sleep. In a number of patients simultaneous anal recordings revealed the presence of slow waves and falls in pressure, some of which were associated with a simultaneous rise in pouch pressure.

Relationship of small bowel motility to ileoanal reservoir function

Some patients with an ileoanal reservoir have a high defecation frequency, despite a good anatomical result and the absence of pouchitis. This study aimed to determine whether variation in function is related to a difference in small bowel motility proximal to the reservoir and if small bowel motility is propagated into the reservoir. Ambulatory small bowel and reservoir motility was studied for 24 hours in five patients with good function (median bowel frequency 4 per day, range 3-6) and seven subjects with poor function (median bowel frequency 12 per day, range 10-20). Five solid state pressure sensors were positioned in the small bowel and one in the reservoir. During the fasting nocturnal period (2300-0800 h), patients with poor function had a median of 10 (range 5-13) migrating motor complexes (MMC), significantly greater (p = 0.03) than the corresponding median number of 3 (range 2-7) in patients with good function. A total of 120 MMCs were observed in the whole series of 12 patients. Of these only two were propagated from the small bowel into the reservoir. Discrete clustered contractions were not propagated into the reservoir, although prolonged propagated contractions did pass into the reservoir in one patient. Patients with poor function had similar 24 hour stool output and radiological reservoir size to those with good function, but the median maximum tolerated volume on reservoir distension was 290 ml (range 160-450) for patients with poor function compared with 475 ml (range 460-550) for patients with good function (p = 0.005). Small bowel motility proximal to the reservoir bears an important relationship to pouch function and defecation frequency. Propagation of coordinated proximal small intestinal motility into the reservoir is rare.

Anorectal function in children after ileoanal pull-through

Mucosal proctectomy and ileoanal pull-through is increasingly used in children requiring total colectomy for ulcerative colitis or familial polyposis. Excellent continence can be achieved with this procedure, and it avoids proctocolectomy and permanent ileostomy. We have evaluated prospectively anorectal function in nine consecutively treated children who underwent ileoanal pull-through. Patients were 8 to 17.5 years of age (median, 11.3 years) at the time of surgery; seven had ulcerative colitis, and two had familial polyposis. Anorectal evaluation was performed before colectomy and ileoanal pull-through, following ileoanal pullthrough, after rectal training, and then at yearly intervals. A biofeedback "rectal training" program was instituted 6 weeks after ileoanal pull-through and a contrast study documenting integrity of the pouch. The program consisted of an initial biofeedback session with the motility unit, followed by daily instillations, through a catheter, of progressively larger volumes of water (from 1 to 6 oz, increasing 1 oz per week) into the ileal pouch. Patients were instructed to retain the water and participate in normal activities after the instillation. This protocol acclimated the patient to sensing distension of the pouch and using the sphincters. The follow-up period ranges from 1 to 4.5 years (median, 2.2 years). All patients are continent by day and night. One patient has nocturnal incontinence with episodes of pouchitis. Stool frequency is three to eight movements per day (median, four), with none at night. Preoperative resting rectal sphincter pressures averaged 74.3 +/- 23.1 mm Hg (mean +/- standard deviation), and a maximum squeeze pressure was 93.9 +/- 25.3 mm Hg.(ABSTRACT TRUNCATED AT 250 WORDS)

Previous subtotal colectomy with ileostomy and sigmoidostomy improves the morbidity and early functional results after ileal pouch-anal anastomosis in ulcerative colitis

The aim of this work was to study the effects of previous subtotal colectomy (STC) with ileostomy and sigmoidostomy on the outcome of ileal J-pouch-anal anastomosis (IPAA) in patients with acute ulcerative colitis. Between 1983 and 1991, we conducted a prospective, nonrandomized study of 156 patients who underwent IPAA in our center. Fifty-five patients (34.3 percent) had undergone STC with ileostomy and sigmoidostomy for either severe acute colitis (36.5 percent of cases) or nonresolving acute colitis (63.5 percent) up to six months before IPAA with covering ileostomy. There were no perioperative deaths; six patients (11 percent) developed complications requiring reoperation (three cases of pelvic sepsis, two occlusions, and one stenosis of the ileostomy). IPAA was successfully carried out at a later stage in all cases. The results of IPAA in these patients were compared with those in 78 patients who underwent the classical two-stage IPAA procedure. The rates of pelvic sepsis and postoperative occlusion were lower in the subgroup of patients who underwent the three-step procedure. Three months after closure of the ileostomy, the mean number of daily stools was significantly lower in the patients who had undergone prior STC (5.09 vs. 5.9), but there was no significant difference between the two groups with regard to diurnal and nocturnal continence, the need to wear a pad, discrimination between gas and stools, or the use of antidiarrheal medication. In addition, there was no significant difference at one year in terms of functional parameters. We conclude that STC is a simple and safe procedure for the treatment of a severe attack of colitis and that it does not compromise the results of later IPAA. Because it does not increase the morbidity of subsequent IPAA and is associated with more rapid functional recovery, STC appears to be suitable for the treatment of patients with nonresolving acute colitis before the onset of malnutrition or steroid dependency.

The two-chamber ileal pelvic reservoir--an alternative design

A new ileal pouch design, combining an upper triplicate ileum with a lower duplicate ileum, is described. The physical characteristics of this two-chamber reservoir would lead to better functional results by delaying the filling time of the reservoir.

Relationship between anal canal tone and rectal motor activity

The anal sphincters facilitate fecal continence by maintaining a pressure barrier; whether proximal contractile events influence this barrier is unknown. The aim of this study was to determine whether a relationship exists between anal canal pressures and rectal motor activity. A fully ambulatory system for prolonged pressure recording was developed. In 12 healthy subjects (seven males and five females; mean age, 35 years; range, 22-43 years), a flexible transducer catheter (outside diameter, 4.5 mm) was introduced endoscopically such that sensors were 2, 3, 8, 12, 18, and 24 cm from the anal orifice. Twenty-four-hour spontaneous motor activity was stored in a 2.5-megabyte portable recorder for later transfer to a Microvax II for computerized analysis and display. Mean anal canal pressure was calculated, and rectal motor complexes (RMCs) were characterized. Mean and canal resting pressure was 75 +/- 12 mmHg. During sleep, anal pressures displayed cyclic decreases (mean periodicity, 1.6 hours; range, 1-4 hours), during which the mean +/- SD pressure trough was 15 +/- 4 mmHg (range, 8-21 mmHg). RMCs were identified in all subjects: mean frequency, 16 per 24 hours (range, 12-22 per 24 hours); duration, 15.3 minutes (range, 8-35 minutes); contractile frequency, two to three per minute; mean peak amplitudes, 58 +/- 18 mmHg; and periodicity, 78 +/- 24 minutes (range, 35-265 minutes). Importantly, an RMC was invariably accompanied by a rise in mean anal canal pressure and contractile activity such that pressure in the anal canal was always greater than pressure in the rectum. Anal canal relaxations never occurred during an RMC. Motor activities of the rectum and of the anal canal may be related; the onset of rectal contractions was accompanied by increased resting pressure and contractile activity of the anal canal. This temporal relationship represents an important mechanism preserving fecal continence.

The results of pouch surgery after ileo-anal anastomosis for inflammatory bowel disease: the manometric assessment of pouch continence and its reservoir function

Anal sphincter function after restorative proctocolectomy has mainly been investigated by anal manometry. A significant decrease of basal pressure up to 45%, has been recorded postoperatively, possibly due to sphincter stretch during endoanal mucosectomy. Both abdominal mucosectomy and anastomosis at the level of the anorectal ring have been reported to prevent anal sphincter damage and lead to better continence. The striated sphincter is not significantly affected by the surgical procedure. Pouch-anal inhibitory reflex is partly maintained in the presence of a rectal cuff which leaves the ganglionic plexus unaltered; a satisfactory continence is also retained in the absence of the reflex when the rectum is totally excised. Pouch capacity, compliance and motility have been investigated by endoluminal balloon and probes. Pouch emptying has been studied by a "porridge" test, by a semi-solid medium labelled with technetium-99, and by other methods. A more effective storage function is achieved by large capacity reservoirs which lower the bowel frequency. The motor response to pouch distension, to a meal, and to pharmacological stimuli is usually counteracted by sphincter contraction. Ileal hypermotility may lead to fecal leakage mainly in the presence of weak sphincters. Poor pouch emptying may be related to an anal stricture.

The internal anal sphincter: mechanisms of control and its role in maintaining anal continence

The human IAS has particular structural and functional characteristics. This smooth muscle constantly generates rhythmic electrical slow waves, but no action potentials. The slow waves are linked to calcium fluxes and both are essential for mechanical activity, i.e. the ASPW. The IAS is pharmacologically characterized by the presence of alpha excitatory and beta inhibitory adrenergic receptors. Cholinergic drugs have an indirect effect through the release of an inhibitory neurotransmitter, very probably VIP, from NANC nerves. The myogenic activity of the IAS is enhanced by its extrinsic sympathetic innervation. Thus, at rest, the IAS is in a state of partial tetanus and contributes approximately 55% of the MABP. Because the IAS ring cannot be completely closed, the anal mucosa and the haemorrhoidal plexuses fill the gap. By compressing these tissues, the IAS perfectly closes the anal canal to retain not only solids but also fluid stool and gas. Acute rectal distension and rectal activity, mainly through intramural pathways, induce reflex IAS relaxation, permitting the rectal contents to be sampled by receptors in the upper anal canal while continence is temporarily maintained by EAS activity and by expansion of the haemorrhoidal cushions. There is a correlation between the volume of rectal distension and the parameters of IAS relaxation. At maximal IAS relaxation, ASPW are absent, indicating the completeness of the inhibition. Although this RAIR is not essential for defecation, insufficient relaxation may be implicated in constipation. Hyperactivity of the IAS resulting in a high MABP and AUSPW has been considered both as a cause and as an effect in haemorrhoids and anal fissure. Continence for fluids and gas is impaired if IAS activity is decreased (i.e. a low MABP), either by direct trauma or by damage of its sympathetic innervation. Severe faecal incontinence will develop when the contractility of both the IAS and the EAS is affected.

Ileoanal pouch compliance and motor function

Measurement of intrapouch pressure during continuous distension with water (pouchmetrography) was performed in ten patients with good pouch function after restorative proctocolectomy and a 'normal' baseline pressure curve was constructed from the mean pressures at 50-ml intervals. Eight other patients with poor pouch function were studied and the two groups were compared. Patients with poor function had significantly lower maximum tolerated volumes (297.5 versus 565 ml, P less than 0.02) and volumes which caused urgency (135 versus 265 ml, P less than 0.02). Baseline pressure curves were above the upper limit of the normal range (mean plus two standard deviations) for a substantial proportion of the recording in six of the patients with poor function. Large, isolated contraction waves were recorded in six of ten patients with good function and in three of those with poor function. Rhythmic waves were frequently seen in both groups but were more prominent in patients with poor function. Pouchmetrography is a provocative test of pouch motor function which may unmask abnormal muscle activity resulting from reduced compliance or a primary motility disorder.

Anal sphincter-saving operations for chronic ulcerative colitis

Three anal sphincter-saving operations--ileorectostomy, ileal pouch-anal anastomosis, and ileal pouch-distal rectal anastomosis--are currently being used in the surgical treatment of chronic ulcerative colitis. All three operations remove the disease, or most of it, and yet they maintain transanal defecation, reasonable fecal continence, and a satisfactory quality of life. All three avoid permanent abdominal ileostomy. Ileorectostomy is the easiest to perform, but it leaves residual disease in the remaining rectum and proximal anal canal that may cause symptoms and that may predispose the patient to cancer. In contrast, ileal pouch-anal anastomosis, although a more technically demanding procedure, totally eradicates the colitis. Its main drawbacks--frequent stooling, nocturnal fecal spotting, and pouchitis--are usually satisfactorily treated with loperamide hydrochloride and metronidazole. Ileal pouch-distal rectal anastomosis is somewhat easier to perform than ileal pouch-anal anastomosis and may result in less nocturnal fecal spotting. Like ileorectostomy, however, the operation leaves residual disease in the distal rectum and proximal anal canal. Considering all of these factors, the ileal pouch-anal operation is preferred today for most patients who require surgery for chronic ulcerative colitis.

Function after anoabdominal rectal resection and colonic J pouch--anal anastomosis

Twenty-eight patients undergoing anoabdominal resection of the rectum with construction of a colonic J reservoir and eight patients without a reservoir were studied 2 years after surgery. Frequency of defaecation and daytime soiling were inversely correlated with the maximum tolerable volume of the colonic J pouch. The distensibility and threshold volume of those with a pouch were significantly greater than in those without a pouch 6 months or more after stoma closure. Anal resting pressure, squeeze pressure, anal canal length and a positive inhibitory reflex were similar in both groups. Anal resting pressure, squeeze pressure and pouch distensibility correlated with frequency of defaecation in the stable phase. Pouch construction may improve the patient's quality of life in the adaptation phase.

Autotransplantation of the pylorus sphincter at the terminal abdominal colostomy. Experimental study in dogs

A method for constructing a continent colostomy has been tried in dogs. The pylorus sphincter with blood supply by the left gastroepiploic vessels was transposed around or anastomosed to the terminal abdominal colostomy in five dogs. One dog had a colostomy without pylorus transplantation. Evaluation was by clinical (consistency and weight of fecal material and number of defecations per day), radiologic, and manometry studies. There was no difference in the clinical data. In all the dogs, the radiologic study demonstrated emptying of the contrast medium to the peristomal skin. By manometry one high-pressure zone was demonstrated, and, in all dogs with a transposed or anastomosed pyloric segment, the average resting pressure was superior to that of the control dog. However, the transposed pylorus sphincter alone was not sufficient to control continence.

Clinical and functional outcome after restorative proctocolectomy

Restorative proctocolectomy and ileal pouch-anal anastomosis (IPAA) has been carried out on 88 patients since 1982. Three different pouch designs (J, S and W) were used. Ten pouches had to be removed. Detailed analysis was performed on 61 patients (J = 23, S = 15, W = 23) whose pouches had been functioning for at least 6 months. There was no significant difference in surgical complications before or after ileostomy closure between pouch designs but the hospital stay was greater after construction of an S pouch (P less than 0.05). There were no significant differences in stool frequency, degree of continence or urgency between the three types. Twelve patients with J pouches required antidiarrhoeal medication compared with only one with S and five with W pouches. Only seven patients with S pouches could defaecate spontaneously compared with 22 with W pouches and all patients with J pouches (P less than 0.001). Twenty-five of 29 patients who had preservation of the anal transition zone had perfect continence compared with 23 of 32 with a mucosal proctectomy (P = n.s.). Pouchitis occurred in 13 patients, all of whom had ulcerative colitis. In a subgroup of 23 patients, pouch evacuation was assessed scintigraphically. There was no difference in pouch capacity or total volume evacuated, but spontaneous evacuation was better in J and W pouches compared with S pouches.

Pouch dynamics--a simple test of ileo-anal pouch evacuation

A simple technique for quantifying ileo-anal pouch evacuation has been used to compare patients with good pouch function and fully spontaneous defaecation (n = 10) to patients with a symptomatic disorder of pouch evacuation (n = 10), usually due to a pouch-anal stricture (n = 7). Pouch emptying was significantly less efficient in those with disordered evacuation (median 54% evacuated) than in those with good function (median 98% evacuated, p = 0.02) and significantly slower (median 22.4 sec vs 5.2 sec to evacuate 75% of instilled barium, p less than 0.02) even when of comparable efficiency. Testing of four further patients with high stool frequency but neither stenosis nor symptomatic difficulty with evacuation excluded a significant disorder of evacuation in three but identified inefficient emptying in the fourth. This test may prove useful in the investigation of patients with poor pouch function of uncertain origin.

The effects of atropine or benzilonium on pelvic pouch and anal sphincter functions

Anticholinergic drugs are used on an empirical basis for treatment of functional disturbances after restorative proctocolectomy, but their mode of action on ileal pouch performance is mainly unknown. We studied the acute effects of atropine or benzilonium on pouch characteristics and anal sphincter function in 20 patients with a pelvic pouch. Pouch volume was increased by 27% by atropine at distension with 20 cm H2O (p less than 0.01). Benzilonium tended to have a similar effect, but the changes did not reach statistical significance (p = 0.06). Pouch contractility, as reflected by volume fluctuations and pressure changes during distension, was almost abolished by both drugs. Sensory thresholds for sense of filling and, particularly, urge were raised. Resting anal pressure was slightly lowered, whereas no significant effect was found on maximal squeeze pressure. In conclusion, anticholinergics appear to have specific properties of action on small-intestinal reservoirs, constituting possible explanations for the empirically observed beneficial effects of anticholinergic treatment of functional disturbances after restorative proctocolectomy.

Comparative intrinsic and extrinsic compliance characteristics of S, J, and W ileoanal pouches

Although compliance of the ileoanal reservoir pouch has been shown to affect function, previous compliance studies may have been influenced by the compliance of the small bowel proximal to the pouch and by supporting pelvic structures. The following study was designed to isolate the pouch and to compare intrinsic and extrinsic factors influencing pouch compliance. Thirty-three mongrel dogs underwent rectal mucosectomy and proctocolectomy with S-pouch (S) in nine, stapled J-pouch (SJ) in nine, handsewn J-pouch (HJ) in nine and handsewn W-pouch (SW) in six. At 2 weeks, each dog underwent laparotomy, the small bowel 2 cm proximal to the pouch was clamped, and in vivo pouch compliance was measured using anal balloon occlusion and continuous saline infusion manometry. The pouch was then removed and ex vivo measurements were repeated. Mean compliance slopes between 0 and 40 cm H2O were compared by ANOVA and paired t-tests. In vivo and ex vivo compliance in ml/cm H2O was 3.1 +/- 1.2 and 3.8 +/- 1.6 (P = 0.25) for the S-pouch, 3.1 +/- 0.6 and 5.2 +/- 1.7 (P less than 0.01) for the SJ-pouch, 2.3 +/- 0.5 and 4.8 +/- 0.7 (P less than 0.001) for the HJ-pouch, 3.6 +/- 0.6 and 6.0 +/- 0.7 (P less than 0.001) for the W-pouch. Pearson's correlation coefficient for in vivo and ex vivo measurements of the S, SJ, HJ, and W pouches were r2 = 0.066, 0.001, 0.039, and 0.379, respectively. It is concluded that: 1) Isolated pouch compliance can be accurately measured in experimental animals with proximal and distal occlusion and inflow manometry. 2) In vivo compliance is significantly less in the HJ compared with S, SJ, and W pouches. 3) Differences between in vivo and ex vivo compliance of SJ, HJ, and SW pouches are significant. 4) In vivo and ex vivo compliance determinations correlate poorly. 5) Extrinsic factors contribute significantly to pouch compliance.

Clinical and physiological study of anal sphincter and ileal J pouch before preileostomy closure and 6 and 12 months after closure of loop ileostomy

Spontaneous evolution of pouch and anal function, and absorption features has been assessed in 15 patients who underwent proctocolectomy with J ileal pouch anastomosis without conservation of a rectal muscular cuff. All the patients were studied before preileostomy closure and six and 12 months after the closure of the protection loop ileostomy. Stool frequency was identical at six and 12 months (mean +/- SEM: 5.0 +/- 0.4 and 5.3 +/- 0.5/day, respectively). Sixty-six percent of patients at six months and 40% of patients at 12 months need to defecate at least one time during night. Stool weight as well as steatorrhea decreased significantly six months after the closure of loop ileostomy (P less than 0.05). Mean resting anal pressure remained unchanged six and 12 months after closure of the loop ileostomy (41 +/- 6 and 45 +/- 5 cm H2O, respectively). Maximum squeeze anal pressures increased significantly at six (P less than 0.05) and 12 months (P less than 0.05). The rectoanal inhibitory reflex was always absent at the same period. The maximum pouch capacity increased significantly during the first six months (P less than 0.01) from 142 +/- 17 to 279 +/- 27 ml. The maximum infused volume during a saline continence test was not significantly different at six and 12 months; the percentage of evacuation of the reservoir and the volume at which the first ileal contraction appeared in the reservoir increased significantly (P less than 0.05) at six and 12 months. In conclusion, in patients with ileoanal anastomosis and pouch reservoir, the closure of the loop ileostomy is associated with spontaneous modifications of the anal and pouch parameters.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of stool consistency on rectal and neorectal emptying

Although stool consistency is considered to be an important component of anorectal continence, its effect on rectal emptying has never been quantitated. In 12 healthy volunteers and 12 patients after ileal pouch-anal anastomosis (IPAA) (46 +/- 5 months after the operation; mean +/- SEM), perfused anal manometry was performed; movements of the anorectal angle were quantitated scintigraphically; and rectal capacity and compliance were measured by air insufflation of an intrarectal balloon at three infusion rates. The efficiency of rectal evacuation of three consistencies (5 percent, liquid; 7.5 percent semisolid gel; 11.25 percent solid gel; w/w) of Tc99m labeled artificial stool (aluminum magnesium silicate gel) was quantitated by gamma camera imaging. No abnormalities of pelvic floor function were demonstrated in either controls or patients. The mean neorectal capacity and compliance of patients with IPAA did not differ from control, (capacity; IPAA: 215 +/- 22 ml vs. control; 245 +/- 29 ml; compliance; IPAA: 5.5 +/- 0.7 ml/cm H2O vs. control; 6.6 +/- 0.7 ml/cm H2O; P greater than 0.05). In controls, the percentage of the 7.5 percent consistency evacuated (81 +/- 5 percent, mean +/- SEM) was significantly more than the percentage evacuation of either the 5 percent consistency (67 +/- 7 percent) or the 11.25 percent consistency (77 +/- 2 percent) (P less than 0.05). After IPAA, the mean overall percent evacuation of the three stool consistencies was significantly less than control (52 +/- 6 percent after IPAA; 75 +/- 5 percent control, P less than 0.05). However, there was no significant difference in neorectal emptying between the liquid, the semisolid gel and the solid gel (56 +/- 6, 55 +/- 6, 51 +/- 9 percent, respectively, P greater than 0.1). We concluded that in healthy subjects but not in patients after IPAA, stool consistency affected the efficiency of evacuation of enteric content.

Functional comparison between double and triple ileal loop pouches

Ileal pouch function in 35 patients operated upon by the same surgeon were compared. Seventeen of the patients had a double loop (J) ileal pouch-anal anastomosis (IPAA) and 18 a triple loop (S) pouch. The patients were examined a mean of 27.9 months and 5.1 months, respectively, after ileostomy closure. Ten of the S-pouch patients were evaluated more than 6 months (S greater than 6 months), mean 9.1 after ileostomy closure. There were no differences in the mean maximum resting pressures or maximum squeeze pressures between the groups. The incidence of daytime and nocturnal leakage was lower in the S-pouch group, 22 and 29 percent, than in the J group 29, and 53 percent. Though the mean maximum tolerated volume (MTV) of the S-pouch group was greater than the J group, the difference was not statistically significant. The difference in the mean compliance between the J- and S-pouch groups and the J and S greater than 6 months group was statistically significant (P less than 0.01) and (P less than 0.008). All the patients could evacuate spontaneously. The difference in the 24-hour frequency of defecation between the S greater than 6 months and J group was significant (P less than 0.05), but not between the S and J groups. The median frequency of nocturnal defecation between the S greater than 6 months and J pouch groups was significant (P less than 0.005), but not between the S and J groups. The triple loop S-pouches were more compliant than the J-pouches and had a better functional result as shown by a lower incidence of nocturnal leakage, and a lower frequency of defecation during the day and night.

Ambulatory anorectal physiology in patients following restorative proctocolectomy for ulcerative colitis: comparison with normal controls

The purpose of this study was to determine the manometric activity of ileoanal W pouch reservoirs following restorative proctocolectomy for ulcerative colitis and to compare the results with normal controls. Thirty-one studies were carried out; there were 15 controls (median age 52 years (range 29-80 years), 10 men, 5 women) and 16 pouch patients (median age 40 years (range 28-52 years), 13 men, 3 women). Mid-anal sphincter pressure and 'rectal' pressure were measured with a microtransducer catheter. The signals were digitalized and recorded in a portable electronic memory for later computer display and analysis. The system allowed the study of patients with minimal constraints while fully ambulant. The frequency of sampling (rectal pressure greater than or equal to sphincter pressure), sensation of flatus present and flatus being passed were 7(1-41), 3(1-7) and 1(0-3.5) per hour in the normal controls and 0(0-3), 0(0-1) and 0(0-1) respectively per hour in the pouch patients (P less than 0.001). Compared with the highly dynamic nature of the anorectum in normal subjects the patients with a pouch had very little activity. The sensation of pouch filling and the desire to defaecate were noted on 12 occasions and in six were associated with a rise in pouch pressure greater than 20 mmHg. One patient had nocturnal soiling and this was the only patient in whom frequent pouch contractions were noted. The results suggest that ileoanal pouch motility is usually quiescent and that incontinence in this group may be related to increased pouch activity.