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Barostat examination of proximal site of the anastomosis in patients with rectal cancer after low anterior resection.

Patients who have undergone low anterior resection (LAR) of the rectum for cancer show symptoms of urgency and frequency of defecation after meals. The cause of these symptoms is unclear. It was hypothesized that the functional disorder of the proximal site of the anastomosis after low anterior resection of the rectum often leads to the symptoms and that the 5-HT3 receptor antagonist reduces postprandial colonic contractions. The aim of this study was to assess colon contractions of the proximal site of the anastomosis and the effects of the 5-HT3 receptor antagonist on the contractions. We evaluated 37 patients who had undergone LARs, 17 with high stool frequency (more than four times per day) and 20 with normal stool frequency. In the first part of the study, basal tone, compliance of the proximal site of the anastomosis, and response to a meal (300 kcal) were recorded with a barostat in all patients. In the second part of the study the effects of the 5-HT3 receptor antagonist on contractions of the proximal site of the anastomosis after ingesting a meal was evaluated. Seven healthy controls were also studied for descending colonic tone with a barostat after a meal. Basal barostat balloon volumes showed only small variations in the two post-LAR groups. Compliance of the proximal site of the anastomosis was similar in the two groups. Meal ingestion stimulated contractions of the proximal site of the anastomosis. In patients with high stool frequency the proximal site of the anastomosis contracted earlier than in those with normal stool frequency after a meal. The descending colonic tone of healthy controls did not change after a meal. The 5-HT3 receptor antagonist inhibited postprandial contractions of the proximal site of the anastomosis after LAR. These observations lend support to the idea that gastrocolonic reflex increases in patients who have undergone LAR, leading to high stool frequency. Furthermore, the 5-HT3 receptor antagonist may alleviate the symptoms of urgency and the frequency of defecation.

Adult↗

Effect of pelvic floor muscle contraction on vesical and rectal function with identification of puborectalis-rectovesical inhibitory reflex and levator-rectovesical excitatory reflex.

The effects of pelvic floor muscle contraction on rectal and vesical function were studied in 19 healthy volunteers with the aim of shedding light on some of the hitherto vague aspects of the mechanisms involved in micturition and defecation and their disorders. Rectal and vesical pressures were recorded during puborectalis (PR) and levator ani (LA) muscle stimulation with the rectum or urinary bladder empty and full. Muscle stimulation was effected by needle EMG electrode. The pressure responses to stimulation of the PR and LA muscles were also recorded with these muscles and the rectum and urinary bladder individually anesthetized in 12 of the 19 subjects. The test was repeated using saline instead of xylocaine. PR and LA muscle stimulation produced no pressure response in the empty rectum or bladder. Upon rectal balloon distension with a mean of 156.6+/-34.2 ml of carbon dioxide the mean rectal pressure was 64.6+/-18.7 cm H2O, the subject felt the urge to evacuate and the balloon was expelled to the exterior. On PR muscle stimulation at rectal distension with the above volume, the subject did not feel the urge to evacuate, the rectal pressure was 8.2+/-1.6 cm H2O and the balloon was not expelled. Upon LA stimulation at the same volume, the urge persisted, the rectal pressure was higher and the balloon was expelled. Vesical filling with a mean of 378.2+/-23.6 ml of saline initiated the urge to urinate and elevated the vesical pressure. PR muscle stimulation at this volume aborted the urge and pressure elevation, while LA stimulation caused more elevation of the vesical pressure and spontaneous micturition. Bladder filling with a mean of 423.6+/-38.2 ml produced high vesical pressure and spontaneous urination, both of which were prevented by PR muscle stimulation but not by LA muscle stimulation. Stimulation of the PR and LA muscles during individual anesthetization of the rectum, bladder or PR and LA muscles resulted in no significant rectal or vesical pressure changes. Repetition of the test using saline instead of xylocaine resulted in rectal and vesical pressure responses similar to those without the use of saline. In conclusion, the decline in rectal and vesical responses upon PR muscle contraction indicates a reflex relationship which we term 'puborectalis rectovesical inhibitory reflex'. This reflex is suggested to abort the urge to defecate or urinate. In contrast, LA muscle contraction produced rectal and vesical pressure elevation which is suggested to be mediated through the 'levator rectovesical excitatory reflex'. 'This reflex is probably evoked to promote rectal and vesical evacuation.

Adolescent↗

Surgery for ulcerative colitis in pediatric patients: functional results of 10-year follow-up with straight endorectal pull-through.

Children and adolescents affected by ulcerative colitis (UC) frequently require colectomy because of refractory or chronic symptoms. The aim of this paper is to present our experience and 10-year follow-up results of 28 patients who underwent endorectal pull-through (ERPT) as surgical treatment for UC, with special regard to surgical complications, stooling patterns (frequency of defecation, stool consistency, urgency period), fecal incontinence, and quality of life. A retrospective chart review of these patients was performed to evaluate age at colectomy, indication for surgical treatment, operative procedures, technical details, and early or late complications. Frequency of defecation was less than twice per day in two patients, between three and five times per day in nine patients, and more than six times per day in 10 patients. Stool consistency was normal in 14 patients, loose in five, and liquid in only two cases. Urgency period was normal (minutes) in 14 patients, short (seconds) in four, and absent in three. Ten patients (47%) have perfect or good fecal continence, whereas 11 (52%) patients present moderate to total incontinence. The self-reported emotional health was good in most of the patients. A large number are progressing well at school and are coping with their operations. Studies of quality of life in UC patients who underwent surgical treatment in childhood or adolescence, comparing as well the results according to the surgical technique adopted, must be encouraged.

Adolescent↗

The treatment of internal anal sphincter achalasia with botulinum toxin.

Internal anal sphincter (IAS) achalasia is a disorder of defecation in which the IAS fails to relax. Botulinum toxin (BT), which has been successfully used to relax the anal and lower esophageal sphincters, was injected twice into the IAS of one adolescent and three infants with manometric, radiologic, and in 2 cases histochemical diagnosis of anal achalasia: in the adolescent a third injection was necessary. Spontaneous defecation was achieved in all patients following the second injection. In one case a diagnosis of short-segment Hirschsprung's disease was obtained after the second injection. Local infiltration of BT into the IAS proved effective in the treatment of IAS achalasia. Double-blind studies and longer follow-up periods are needed to better evaluate these preliminary results and define the limits of this promising therapy.

Botulinum Toxins, Type A↗

Rectocele repair improves evacuation and prolapse complaints independent of anorectal function and colonic transit time.

BACKGROUND AND AIMS: Evacuation disorders associated with a rectocele can be improved by rectocele repair. This study investigated whether anorectal function tests results change after rectocele repair. PATIENTS AND METHODS: Fourteen patients with 2nd or 3rd degree rectocele and evacuation disorder were treated by posterior colporrhaphy and evaluated pre- and postoperatively (after 8 months, range 3-14) using questionnaires, anal manometry and endosonography, rectal barostat testing, and colonic transit time measurement with radio-opaque markers. Results from female controls were used for comparison. RESULTS: Preoperatively, rectocele patients had high maximal basal sphincter pressures, large sphincter lengths, and low maximal squeeze pressures, with an anal sphincter defect in seven and lower visceral sensitivity scores than in controls. Postprandial rectal responses (more than 10% decrease in postprandial volume after 1 h) were found in 3 of 14 patients compared to 2 of 11 parous and 9 of 11 nulliparous controls. After repair, a rectocele of 2nd degree was found in four patients. Questionnaire scores were significantly decreased for straining, evacuation disorder, manual support, and protrusion. Overall patient satisfaction with the operation scored 8.25 (range 3-10). Defecation frequencies and stool consistencies were unaltered. Anal pressures, rectal compliance-curves, visceral sensitivity, and colonic transit times were unaltered after the rectocele repair. CONCLUSION: Rectocele repair improved complaints of evacuation disorder and protrusion, but defecation frequency and stool consistency were not affected. Anorectal function was unaltered after rectocele repair. Selection of patients for rectocele repair should be performed based on evacuation and protrusion complaints, anorectal function, or colonic transit time measurements have a limited role.

Adult↗

Rectal pacing in patients with constipation due to rectal inertia: technique and results.

In a previous study we determined the rectal pacing parameters needed for rectal evacuation in patients with rectal inertia. Here we investigated the effect of rectal pacing on rectal myoelectric activity, motility, and evacuation in ten patients with constipation due to rectal inertia. A pacemaker was implanted in a subcutaneous pocket above the inguinal area, with a lead threaded in the anal submucosa to be hooked at the rectosigmoid junction. The effect of rectal pacing on rectal electric activity was investigated by inserting two recording electrodes to the rectal mucosa. The patients were then trained for home pacing. No waves were recorded from the rectum at rest. On rectal pacing, slow waves or pacesetter potentials (mean frequency 2.3+/-1.1 cpm, amplitude 0.86+/-0.1 mV, velocity 3.4+/-1.6 ms) were registered after a latency period of 5.2+/-1.6 min. Rectal evacuation, on pacing, occurred in seven of the ten patients. The three who showed no significant response exhibited low wave parameters. Three of seven patients were able to evacuate spontaneously without pacing after having performed daily pacing for 5-6 months. The pacemaker was removed in six patients (three failures and three after spontaneous defecation). Thus rectal pacing succeeded in inducing rectal evacuation in 70% of the patients. The procedure failed in three patients. Three had spontaneous defecation after a few months of rectal pacing. No complications were encountered, and the method was tolerated and acceptable. Further studies on a large group of patients are required.

Action Potentials↗

Efficacy and safety of postoperative chewing gum for gastrointestinal recovery in children undergoing surgery: an updated systematic review and meta-analysis.

Chewing gum may stimulate gut motility through a "sham feeding" mechanism, but evidence in children is limited. We performed an updated systematic review and meta-analysis of randomized controlled trials comparing chewing gum plus usual care versus usual care alone in patients younger than 18 years undergoing any surgery. We searched five databases through June 2025. Primary outcomes were the time to first flatus, time to first defecation, and postoperative length of stay (LOS). Certainty was assessed with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Ten studies (n = 649) were included: abdominal surgery (5), spinal fusion (3), and tonsillectomy (2). Chewing gum may result in little to no difference in the time to first flatus (MD - 3.58 h, 95% CI - 8.08 to 0.91) or first defecation (MD - 3.23 h, 95% CI - 6.63 to 0.18), both with low certainty. LOS evidence was very uncertain (MD - 0.18 days, 95% CI - 0.70 to 0.33). Subgroup analyses suggested shorter LOS after abdominal surgery (MD - 0.60 days, 95% CI - 1.99 to 0.79) but not after spinal fusion (MD 0.10 days, 95% CI - 0.29 to 0.50; p for interaction = 0.0362). The benefits of postoperative chewing gum in children remain uncertain, with potential surgery-specific differences in LOS warranting investigation.

Humans↗

Laparoscopic management of rectal endometriosis.

PURPOSE: Surgical treatment of females with rectal endometriosis is challenging. The aim of this study was to review the results of laparoscopic intervention in the management of females with this complex disorder. METHOD: All cases of complex tertiary referral pelvic endometriosis requiring laparoscopic surgical intervention of the rectum were identified and reviewed from a prospective database. RESULTS: Between April 1996 and August 2004, 95 patients with pelvic endometriosis involving the rectum had laparoscopic surgical procedures performed by one gynecologist and one colorectal surgeon. Eighty percent of rectal procedures were completed laparoscopically. Forty-three (45 percent) were treated with diathermy excision, 18 (19 percent) had shave partial-thickness disc excision, 20 (21 percent) had full-thickness disc excision (including 14 endoanally using a circular stapler), while 14 (15 percent) were managed with laparoscopic-assisted segmental low anterior resection. A history of rectal pain during defecation present only during menstruation (adjusted odds ratio=8.6, 95 percent confidence interval (CI)=1.8-41.2) and previous laparoscopy (adjusted odds ratio=3.2, 95 percent CI=1.2-8.3) independently predicted a need for more extensive surgery than diathermy excision. There were no rectal anastomotic leaks, with 8 percent overall morbidity. The only significant predictor of ongoing postoperative symptoms was a history of dyspareunia (P=0.03). CONCLUSIONS: Patients with complex endometriosis of the rectum can be safely managed laparoscopically using a multidisciplinary approach. This case series suggests that a history of rectal pain during defecation that occurs only during menstruation is predictive of females with more extensive rectal disease.

Adult↗

A pilot study of the effects of sildenafil on stool characteristics, colon transit, anal sphincter function, and rectal sensation in healthy men.

Nitric oxide is an important mediator of gut smooth muscle relaxation and visceral sensation. Sildenafil results in stimulation of the nitric oxide-cyclic GMP pathway. We sought to determine the effects of daily sildenafil administration on colorectal function. Over a 4-week period, sildenafil was administered during weeks 2 and 3. Stool frequency and consistency were assessed daily. Anorectal manometry, rectal sensation, and colon transit testing were performed at the end of weeks 1 and 3. Ten healthy men were studied. No significant differences in segmental or total colon transit time were noted; however, significant changes in stool frequency and trends toward decreased stool consistency were noted during sildenafil use. A trend toward reduced resting anal sphincter pressure was seen after sildenafil. Rectal volumes to first sensation and desire to defecate were significantly increased after sildenafil on test day 2 only. Additionally, volumes to desire to defecate and maximal tolerable volume were significantly increased before sildenafil on test day 2 compared to before sildenafil on test day 1. We conclude that daily administration of sildenafil is well tolerated and results in alterations in colorectal function.

Adult↗

Surgical approaches to pediatric defecatory disorders.

Defecation is one of the most basic of human activities. Problems with evacuation of feces have plagued people since the beginning of time. In modern society, defecatory disorders are the source of embarrassment, discomfort, and stress. Society's lack of openness on this subject forces many people to endure their affliction silently. Nevertheless, although these conditions consume significant medical resources, little research has been done on their causes and treatment. This review summarizes recent developments in surgical treatment of children with these disorders, either in the ability to pass stool or the ability to control defecation.

Anus, Imperforate↗

Damage to the innervation of the pelvic floor musculature in chronic constipation.

Constipation and defecation straining have been implicated in the pathogenesis of anorectal incontinence. We have studied 24 women with chronic constipation and 20 age- and parity-matched control subjects. Electrophysiologic techniques were used to study the innervations of the puborectalis and external anal sphincter muscles. The results show that damage can occur to the nerve supply of both these muscles in chronic constipation, and that this probably is due to perineal descent during defecation straining.

Adult↗

Changes in colorectal function in severe idiopathic chronic constipation.

Physiologic studies of colorectal and anal function were performed in 25 adult patients with severe idiopathic long-standing constipation compared with 22 age- and sex-matched normal subjects. Only patients with primary severe idiopathic constipation with no known underlying primary etiology have been studied. No significant changes were observed in the resting or squeeze anal canal pressures. There was indirect evidence that rectal sensation was grossly impaired in 17 of the constipated patients: mean values for constant sensation compared with controls being 269 +/- 21 ml and 136 +/- 10.3 ml, respectively (p less than 0.01). The mean anorectal angles during attempted defecation were significantly less in constipated patients compared with controls (p less than 0.001), and 10 patients were unable to evacuate from the rectum a balloon containing 150 ml of a weak barium suspension. Electromyography of the pelvic floor showed increased puborectalis activity on attempted defecation in 9 subjects. Although there was no significant difference in the basal sigmoid motility index between constipated patients and controls, response to intrarectal bisacodyl (5 mg) was impaired in the constipated group, being 479 +/- 22.1 and 735 +/- 24.7, respectively (p less than 0.01). Transit time was significantly delayed in the constipated patients; the percentage of markers passed by constipated patients after 5 days was 39.0 +/- 6.9 compared with 73.9 +/- 2.8 passed by controls (p less than 0.02). These results imply that there is often a motor abnormality of the pelvic floor and the colon in patients with long-standing chronic constipation.

Adolescent↗

Colonic motor response to a meal in acute colitis.

The symptoms of urgency, diarrhea, and abdominal discomfort are exaggerated after a meal in inflammatory disorders of the colon, such as ulcerative colitis. The possible motor correlates of these symptoms were investigated in a model of acute colitis in six dogs. Each dog was instrumented with seven strain gauge transducers, two on the proximal, three on the middle, and two on the distal colon. After an overnight fast, 4-hour fasted recordings were made from the normal colon and after the colon had been cleansed on the previous day with Colyte (Reed & Carnrick, Piscataway, NJ). A 1300-kcal meal was then fed, and the recordings were continued for another 8 hours. Acute colitis was then induced by the perfusion of 10 mL of 75% acetic acid and confirmed with colonoscopy and biopsy. The fasted and postprandial recordings were repeated during the next 5 days. In the control state, ingestion of the meal increased the total duration per hour of contractile activity in the early (0-2 hours) and late (2-8 hours) postprandial periods in the distal colon. In the proximal and the middle colon, a significant increase in motor activity occurred only during the late postprandial period. Similar effects were observed in the cleansed colon. By contrast, there was no significant increase in motor activity after a meal during colitis in any of the postprandial periods in the cleansed or the uncleansed colon. During colitis, there was a significant increase in the incidence of giant migrating contractions in the fasted state. The ingestion of a meal further increased the frequency of giant migrating contractions in the uncleansed colon from 0.4 +/- 0.1 to 1.3 +/- 0.5 per hour in the late postprandial period. There was no significant increase during the early postprandial period. The increase in the late postprandial frequency of giant migrating contractions was associated with an increase in defecation frequency. It is concluded that the motor response of the colon to a meal is absent in acute colitis. The entry of new ingesta into the colon during the late postprandial period stimulates enteric mechanisms to initiate an excessive number of giant migrating contractions. These giant migrating contractions may be related to increased postprandial abdominal discomfort and increased frequency of defecation.

Acute Disease↗

Central and NO mediated mechanisms are involved in the inhibitory effects of CCK on the chicken cecorectal area.

In chickens CCK-8s induces defecation and causes an inhibition of rectal electrical activity (EA) and an increase in cecal motility. In contrast, CCK-4 inhibits the motility of both rectum and ceca. The cecorectal responses to CCK-8s and CCK-4, given intravenously (i.v.), were studied in conscious chickens prepared with electrodes for electromyography; the influence of atropine, phentolamine plus propranolol, hexamethonium and L-NAME on such responses was determined. Atropine and phentolamine plus propranolol did not cause any change in the response to CCK-8s or CCK-4 in the cecorectal area. Hexamethonium only induced a significant decrease in the number of defecations (ND) induced by CCK-8s. L-NAME slightly modified the decrease in rectal EA due to CCK-8s. The effects of intracerebroventricular (i.c.v.) administration of CCK-8s and CCK-4 were also studied. CCK-8s and CCK-4, given i.c.v., caused, in conscious chickens, a slight decrease in cecal EA, in the 15 minutes following administration. This effect was similar to that seen after i.v. administration of CCK-4. In conclusion, our results suggest that the inhibitory action of CCK on chicken rectum is mediated, at least in part, through nitric oxide release. In addition, nicotinic receptors mediate the increase in the ND caused by CCK-8s. Ganglionic, muscarinic, adrenergic and nitrergic blockade were not able to modify the excitatory cecal response to CCK-8s, which may indicate that the receptor mediating this effect is located on the cecal smooth muscle. Finally, the inhibitory action of i.v. CCK-4 on chicken cecum seems to be centrally mediated, as suggested by the fact that i.c.v. administration of either CCK-8s or CCK-4 induce a similar effect.

Animals↗

Lack of an inhibitory effect of hyperprolactinemia on androgen-dependent marking.

An experiment was performed to determine if hyperprolactinemia (chronically elevated serum prolactin levels), which inhibits testosterone-activated male sexual activity, also affects other androgen-dependent behaviors. Thus defecation and urine marking in response to a novel environment were examined in sham-operated and pituitary-grafted (hyperprolactinemic) male rats that had been castrated or castrated and given subcutaneous testosterone implants. Both castration and pituitary grafting significantly inhibited defecation, with the inhibitory effects of hyperprolactinemia being most pronounced in the castrated non-testosterone-treated animals. In contrast, castration significantly reduced the amount of urine marking observed, but pituitary grafting was without effect on this behavior. Thus, although hyperprolactinemia may inhibit sexual activity through an antagonism of the activational effects of testosterone, these results suggest that this effect is specific to sexual behavior and does not involve a more generalized inhibition of the effects of testosterone on androgen-dependent behaviors.

Animals↗

Correlations of motility, defecatory behavior and striatal dopaminergic activity in rats.

The spontaneous motor activity, fecal pellet scores and content of dopamine and its metabolites, dihydroxyphenyl acetic acid and homovanillic acid in corpus striatum were measured in a group of randomly selected Sprague-Dawley rats. The spontaneous motility, fecal pellet scores and neurochemical parameters measured showed significant variations. The correlations between these parameters were investigated. A significant correspondence was seen between the motility, fecal pellet scores and the striatal dopaminergic activity. The implications of the behavioral models of motility and defecation scores in studying the central dopaminergic function is discussed. It is suggested that striatal dopaminergic activity may be responsible not only for motor activity but also may contribute to the de novo emotionality as expressed by the defecation scores in rats.

3,4-Dihydroxyphenylacetic Acid↗

Characterization of stress-induced long-term behavioural changes in rats: evidence in favor of anxiety.

Recently, we reported that rats exposed to one brief session of inescapable footshocks showed a gradually developing and long-lasting decrease in behavioural activity and an increase in defecation in an open field. The aim of the present study was to further characterize the long-lasting changes in behavioural responsiveness to environmental stimuli. For this purpose, behavioural paradigms validated as tools in the preclinical study of the psychobiology of depression were used. Footshocked rats (S) showed a decreased response latency in an one-way avoidance-escape task and decreased immobility in a forced swim test as compared to nonshocked control rats (C) 14 days after shock exposure. These S rats showed decreased behavioural activity and increased defecation as compared to the C rats in an open field test carried out 28 days after footshock exposure. In addition, footshock exposure did not affect the preference for or consumption of a 0.05% saccharin solution on a long-term basis, although a decreased consumption of this solution was evident in S rats on day 1 postshock. These S rats showed an exaggerated immobility response to a sudden reduction in background noise level compared to C rats while placed in a novel environment on day 11 postshock. We conclude that the long-term effects of one short session of inescapable footshocks are not compatible with what is supposed to represent behavioural manifestations of depression in animals. It is argued that the common denominator of shock-induced long-lasting changes is increased behavioural defensiveness, which is more likely related to increased fear and/or anxiety.

Animals↗

Urethral discharge, constipation, and hemorrhoids. New syndrome with report of 7 cases.

A new syndrome in which 7 cases share common clinical features of urethral discharge only at defecation, constipation, and hemorrhoids is reported. The discharge occurred only with constipation. The relationship between urethral discharge, constipation, and hemorrhoids is discussed. The concept that hemorrhoids lead to prostatic venous congestion is put forward. The urethral discharge at defecation seems to be the result of "milking" of the congested prostate by the hard stools. The mechanism of fecal and urinary "milking" of the prostate is discussed. The role of the congested prostate in infertilogenesis is presented. It seems that metabolic accumulation in the prostatic, vesicular, and ampullary secretions affected the spermatogenic activity as it similarly does in varicocele. Permanent disappearance of urethral discharge and improvement of semen quality were achieved on anoprostatic decongestion by medical treatment, hemorrhoid injection, or hemorrhoidectomy. The syndrome of prostatorrhea, constipation, and hemorrhoids should be considered in patients with idiopathic urethral discharge and in infertile patients.

Adult↗