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Gastrointestinal transit time, frequency of defecation, and anorectal manometry in healthy and constipated children.

Total gastrointestinal transit time (TGITT), frequency of defecation, and anorectal manometry were evaluated in 63 pediatric patients referred for chronic nonorganic constipation; in 39, segmental transit times of the right and left colon and rectum were also measured. TGITT was significantly longer in chronically constipated children than in matched normal controls. Although bowel frequency was highly significantly correlated with TGITT in patients with prolonged transit time, not all children with prolonged TGITT had reduced bowel frequency. Moreover, not all children with constipation had prolonged TGITT. In children with idiopathic chronic constipation, slowing of intestinal transit occurred most frequently at the level of the distal colon and rectum. Anorectal motility variables were not significantly different in children with functional chronic constipation and in normal children. Maximal resting and pressure and mean intrarectal distending volume causing threshold inhibition in constipated patients did not significantly differ from the control values. Therefore, anorectal manometry did not detect relevant motor abnormalities in constipated children.

Anal Canal↗

Captopril alters schedule induced polydipsia, urination, and defecation in rats.

Schedule induced polydipsia, urination and defecation were examined in rats that received training on a fixed interval 2 min schedule of food reinforcement. In Phase I of the experiment, animals received peripheral injections of captopril (an angiotensin conversion enzyme blocker, 0.5 or 50 mg/kg), or equivalent volumes of 0.9% saline. The results showed that low doses of captopril (0.5 mg/kg) significantly increased both operant responding and the adjunctive behaviors. High peripheral doses of captopril significantly reduced responding and schedule induced behavior. In Phase II of the experiment, animals received either low peripheral doses of captopril (sc 0.5 mg/kg), or low doses that were coupled with central injections (i.e., 0.12 mg icv + 0.5 mg/kg sc). As observed in Phase I, low peripheral doses of captopril enhanced behavior, but the enhancement effect was eliminated with low (0.12 mg) central administration. The overall results are consistent with past research examining captopril effects on non-operant, meal-induced drinking. Yet since captopril affected operant responding and adjunctive behaviors similarly, the findings suggest that angiotensin plays a common role in the motivational processes that precede and follow the arrival of food.

Analysis of Variance↗

The relationship between rectal pain, unpleasantness, and urge to defecate in normal subjects.

Rectal stimulation under normal or pathological conditions evokes numerous sensations. Previous studies have examined rectal stimulation-evoked pain and urge to defecate, but discrepancies in the findings remain because of the different methodologies used in each study and the reporting of sensations only at the end of or after the applied stimuli. Therefore, we conducted a psychophysical study of various aspects of rectal sensation in normal subjects using a variety of distension stimuli and continuous on-line rating of sensation. Ten normal healthy subjects (eight female and two male) were given rectal distension stimuli delivered by a computer-driven barostat. For some experiments, sensation was continuously monitored and rated on a visual analog scale. Subjects first underwent an ascending series of phasic (30 s) distensions to determine how urge, unpleasantness, and pain intensity varied and interrelated as rectal volume and pressure changed. A second series of distensions examined rectal physiology and perception during short phasic (30 s) or long (300 s) distensions at pressures that elicit either moderate urge or moderate pain and while continuously rating these sensations. The McGill Pain Questionnaire was used to assess the multidimensional aspects of rectal pain with each type of distension. The results of the ascending series revealed significant relationships between sensations as pressure and volume increased. The ratings of urge were double that of pain and unpleasantness, whereas unpleasantness and pain ratings were comparable. Isobaric phasic and tonic distensions were associated with an increase in volume (i.e. accommodation) with time. The magnitude of urge with repetitive short isobaric (30 s) distensions was overall not related to the slight increase in rectal volume, while phasic distensions at moderate pain intensity revealed a significant overall relationship between rectal volume and both unpleasantness and pain intensity. Long isobaric distensions evoked sensations that varied over time despite progressive increases in volume, but less variation in sensation was observed during short phasic distensions which also demonstrated a similar increase in rectal volume. Differences in temporal characteristics of sensations evoked by low-pressure distensions eliciting moderate urge versus high-pressure distensions eliciting moderate pain were illustrated by a significantly longer delay to the diminution of non-painful urge versus pain. Therefore, we conclude (1) Differences in the discrimination and the temporal characteristics of urge at subpainful rectal pressures and of pain at noxious pressures suggest that noxious and non-noxious stimuli are processed differently. (2) The overall unpleasantness and pain correlate with rectal volume during accommodation. However, instantaneous evoked sensations can vary independent of volume changes during constant pressure distension. (3) The reported sensation-related responses to tension and stretch will likely be different depending on the degree of accommodation that is occurring. Moreover, the peripheral receptor mechanisms which contribute to controlling this accommodation will also affect the perception of rectal stimuli. (4) Continuous ratings of rectal sensations are valuable in investigating rectal physiology and the multidimensional nature of rectal symptoms.

Adult↗

Acute abdominal pain and urgency to defecate in the young and the old: a useful symptom-complex?

In the belief that "pattern recognition" is an important first step of the diagnostic process, we report our observation of an uncommon and heretofore poorly documented symptom-complex in 10 patients, and suggest that the constellation of abdominal pain and urgency to defecate in the acutely ill surgical patient should raise the diagnostic possibility of intra-abdominal bleeding. In our experience, this is statistically likely to be associated with a ruptured abdominal aortic aneurysm in the old and a ruptured ectopic pregnancy in the young.

Abdomen, Acute↗

Study of the role of the second defecation reflex: anorectal excitatory reflex in the pathogenesis of constipation.

BACKGROUND: Previous studies have shown that anal distension caused rectal contraction, an action mediated through the anorectal excitatory reflex. Anal anesthetization aborted rectal contraction and rectal evacuation was induced by excessive straining. We investigated the hypothesis that inhibition or absence of the anorectal excitatory reflex could lead to constipation. METHODS: We studied 18 patients (mean age +/- SD: 40.6 +/- 5.8 years, 14 women) with rectal inertia, 14 (41.7 +/- 6.6 years, 12 women) with puborectalis paradoxical syndrome, and 10 healthy volunteers (37.9 +/- 4.8 years, 8 women). The rectum was filled with normal saline until urge and then evacuated; residual fluid was calculated. The anal and rectal pressure response to anal balloon distension in increments of 2 mL of saline was recorded by a two-channel microtip catheter. RESULTS: In the healthy volunteers, saline was evacuated as a continuous stream without straining except occasionally at the start of evacuation; no residual fluid was encountered. Anal balloon distension effected notable rectal pressure increase. In rectal inertia patients, evacuation occurred in small fluid gushes produced with excessive straining; residual fluid of large volume was collected. Anal balloon distension up to 10 mL produced no notable rectal pressure changes. The patients with PPS failed to evacuate more than a few mL of fluid despite excessive straining; the volume of residual fluid was considerable. Anal balloon distension caused a notable rectal pressure rise. The results were reproducible. CONCLUSIONS: These results suggest that the defecation reflexes (rectoanal and anorectal) are absent in rectal inertia patients and this presumably denotes a neurogenic disorder. The anorectal reflex is active in puborectalis paradoxical syndrome, but the rectoanal reflex is not, indicating a possible myogenic defect in the puborectalis muscle.

Adult↗

Multidisciplinary behavioral treatment of defecation problems: a controlled study in children with anorectal malformations.

BACKGROUND/PURPOSE: The most frequent consequences of being born with an anorectal malformation (ARM) are problems with fecal continence and constipation, which can have various negative implications. In this prospective, controlled study the effect of multidisciplinary behavioral treatment dealing with these problems is evaluated. METHODS: The effect of multidisciplinary behavioral treatment was studied in 24 children (15 boys, 9 girls; mean age 5.8 years). Thirteen children were allocated to the treatment condition. The 11 children allocated to the waiting list control group also were treated after a waiting period of 6 months. Children underwent follow-up after treatment. RESULTS: Compared with a waiting list control group, the experimental treatment group scores significantly better on 2 important measures ("Templeton," "Percentage of feces in toilet"). Although young children had poorer scores than older children before treatment, no significant differences in the favorable outcome of treatment were found between both groups after treatment. No effect of type of ARM on treatment was found either. The results of multidisciplinary behavioral treatment remain stable over a mean follow-up period of 7 months. CONCLUSION: Multidisciplinary behavioral treatment is an important and valuable supplement to the standard medical treatment of children born with ARM suffering from chronic defecation problems.

Anal Canal↗

Anterior rectocele due to obstructed defecation relieved by botulinum toxin.

Background. Surgical repair of rectocele does not always alleviate symptoms related to difficulty in defecation, and some patients have impaired fecal continence after surgical treatment. To avoid complications of surgical repair, we investigated the efficacy of botulinum toxin in treating patients with symptomatic rectocele. Methods. Fourteen female patients with anterior rectocele were included in the study. The patients were studied by using anorectal manometry and defecography, and then treated with a total of 30 units of type A botulinum toxin, injected into 3 sites, 2 on either side of the puborectalis muscle and the third anteriorly in the external anal sphincter, under ultrasonographic guidance. Results. After 2 months, symptomatic improvement was noted in 9 patients (P =.0003). At the same time, rectocele depth (mean +/- SD) was reduced from 4.3 +/- 0.6 cm to 1.8 +/- 0.5 cm (P =.0000001) and rectocele area from 9.2 +/- 1.3 cm(2) to 2.8 +/- 1.6 cm(2) (P =.0000001). Anorectal manometry demonstrated decreased tone during straining from 70 +/- 28 mm Hg at baseline to 41 +/- 19 mm Hg at 1 month (P =.003) and to 41 +/- 22 mm Hg at 2 months (P =.005). No permanent complications were observed in any patient for a mean follow-up period of 18 +/- 4 months. At 1 year evaluation, incomplete or digitally assisted rectal voiding was not reported by any patient, and a rectocele was not found at physical examination. Four recurrent, asymptomatic rectoceles were noted at defecography. Conclusions. Botulinum toxin injections should be considered as a simple therapeutic approach in patients with anterior rectocele. The treatment is safe and less expensive than surgical repair. A more precise method of toxin injections under transrectal ultrasonography accounts for the high success rate. Repeated injections may be necessary to maintain the clinical improvement.

Adult↗

Stimulation of defecation: effects of coffee use and nicotine on rectal tone and visceral sensitivity.

OBJECTIVE: Coffee and cigarette use is believed to induce bowel movements, although the literature is controversial and precise measurements of rectal tone and sensitivity with a barostat have never been performed. The aim of this study was to assess the effects of coffee and nicotine on rectal tone, compliance and sensitivity. MATERIALS AND METHODS: Sixteen healthy volunteers were recruited for the coffee (n = 8) and nicotine (n = 8) experiments. The experiments were randomly performed in a placebo-controlled crossover design on separate days. In the coffee experiment, 280 ml strong coffee or warm water was drunk and in the nicotine experiment, nicotine (2 mg) or placebo was given sublingually. A rectal barostat procedure was carried out. A flaccid bag, mounted on a catheter, was inserted in the rectum. Continuous pressure distension was exerted to register basal visceral sensitivity and compliance. After rectal adaptation, the stimulus was given. Rectal tone was measured for 1 h, after which continuous pressure distension was repeated. RESULTS: Rectal tone increased by 45% 30 min after coffee intake (p = 0.031) and by 30% after water intake (p = 0.032), but the effects of coffee and water were not significantly different. Rectal tone did not change significantly after administration of nicotine (7%) or placebo (10%). There was no difference in compliance and visceral sensitivity between coffee and water or nicotine and placebo. CONCLUSIONS: Both coffee and warm water have an effect on defecation by increasing rectal tone, but nicotine (2 mg) did not affect rectal tone. Coffee and nicotine did not influence sensitivity or compliance.

Adult↗

Effect of fiber from fruits and vegetables on metabolic responses of human subjects I. Bowel transit time, number of defecations, fecal weight, urinary excretions of energy and nitrogen and apparent digestibilities of energy, nitrogen, and fat.

Twelve men 37 to 58 years of age consumed two diets for a period of 26 days each in a cross-over design. The high fiber diet contained fruits and vegetables and the lower fiber diet contained fruit and vegetable juices. Neither diet contained whole grain cereals or nuts. Some nutrients were added to the low fiber diet in order to make the diets equivalent insofar as possible in all respects except fiber. The inclusion of fruits and vegetables in the diet decreased bowel transit time, increased fecal weight, increased number of defecations, increased fecal excretions and decreased apparent digestibilities of energy, nitrogen, and fat. Six of the 12 subjects had diastolic blood pressure of 80 or more when consuming the low fiber diet. The diastolic blood pressures of these six men were significantly lower when the high fiber diet was consumed.

Adult↗

Dynamic study of the rectal detrusor activity at defecation.

The dynamics of the rectal detrusor at defecation was studied in 29 normal and 10 constipated subjects. The rectal pressure was measured by a ureteral catheter with terminal side holes, while the intra-abdominal pressure was measured by a Foley catheter introduced into the urinary bladder. Simultaneous recording of fecal flow was performed by fecoflowmetry. Assessment of the findings in normal subjects has shown a pre-evacuation rectal pressure elevation which reached its peak with the start of fecal flow and then fell gradually as the flow increased. This was in contrast to the constipated patients in whom the elevated pre-evacuation rectal pressure continued through the whole act of evacuation. Quantitative analysis of the rectal pressure curve could also differentiate between normal and constipated subjects. The significant parameters are the opening pressure and time, the pressure time and the evacuation pressure. The simultaneous recording of the intra-abdominal pressure demonstrates its share in the increase of the rectal pressure.

Adult↗

Electrocardiographic changes in coronary care unit patients during defecation.

Fifty-one consecutive patients admitted to a coronary care unit were monitored for ECG changes while having a total of 63 bowel movements (BM's). Twenty-three patients had proven myocardial infarction while 28 had no acute cardiac disease. ECG changes in patients using either commode or bedpan facilities were compared during defecation. Patients using the commode were found to have a greater increase in heart rate and other nonspecific ECG abnormalities compared to those using the bedpan.

Acute Disease↗

Enhancement of the intrinsic defecation reflex by mosapride, a 5-HT4 agonist, in chronically lumbosacral denervated guinea pigs.

The defecation reflex is composed of rectal distension-evoked rectal (R-R) reflex contractions and synchronous internal anal sphincter (R-IAS) reflex relaxations in guinea pigs. These R-R and R-IAS reflexes are controlled via extrinsic sacral excitatory nerve pathway (pelvic nerves), lumbar inhibitory nerve pathways (colonic nerves) and by intrinsic cholinergic excitatory and nitrergic inhibitory nerve pathways. The effect of mosapride (a prokinetic benzamide) on the intrinsic reflexes, mediated via enteric 5-HT(4) receptors, was evaluated by measuring the mechanical activity of the rectum and IAS in anesthetized guinea pigs using an intrinsic R-R and R-IAS reflex model resulting from chronic (two to nine days) lumbosacral denervation (PITH). In this model, the myenteric plexus remains undamaged and the distribution of myenteric and intramuscular interstitial cells of Cajal is unchanged. Although R-R and R-IAS reflex patterns markedly changed, the reflex indices (reflex pressure or force curve-time integral) of both the R-R contractions and the synchronous R-IAS relaxations were unchanged. The frequency of the spontaneous R and IAS motility was also unchanged. Mosapride (0.1-1.0 mg/kg) dose-dependently increased both intrinsic R-R (maximum: 1.82) and R-IAS reflex indices (maximum: 2.76) from that of the control (1.0) 6-9 days following chronic PITH. The dose-response curve was similar to that in the intact guinea pig, and had shifted to the left from that in the guinea pig after acute PITH. A specific 5-HT(4) receptor antagonist, GR 113808 (1.0 mg/kg), decreased both reflex indices by approximately 50% and antagonized the effect of mosapride 1.0 mg/kg. This was quite different from the result in the intact guinea pig where GR 113808 (1.0 mg/kg) did not affect either of the reflex indices. The present results indicate that mosapride enhanced the intrinsic R-R and R-IAS reflexes and functionally compensated for the deprivation of extrinsic innervation. The actions of mosapride were mediated through endogenously active, intrinsic 5-HT(4) receptors which may be post-synaptically located in the myenteric plexus of the anorectum.

Anal Canal↗

[Feeding and defecation dynamics of Triatoma sordida].

Today, Triatoma sordida is the most frequently captured triatomine in Brazil. For a better understanding of its vectorial potential, its feeding dynamics and dejections behaviour were studied in comparison with Triatoma infestans and P. megistus. The proportion of T. sordida and T. infestans that blood fed on anaesthetized rats did not differ significantly. There was no significant difference in the time elapse between release of the bugs and the initiation of blood feeding. The mean time between completion of a blood meal and the first dejection was significantly lower in T. infestans than in T. sordida. The numbers of insects that defecated during the blood meal or immediately afterwards was similar for both species. Approximately 80 specimens of each of T. sordida, T. infestans and Panstrongylus megistus were offered daily blood meals for 30 minutes, over a period of 30 days. T. sordida bit more frequently than did P. megistus and T. infestans. These data could indicate that T. sordida may not be completely adapted to its host and might have difficulty in complete its blood meal.

Animals↗

Effect of cecectomy on feeding and defecation in rats.

The effect of cecectomy on food intake and defecation was studied in Wistar rats fed ad libitum or under restriction. Food intake, fecal output, dry matter and water content of feces, and numbers of scybala increased significantly in both groups of cecectomized rats. The weight of scybala and their dry matter and water content also increased after cecectomy. Water intake did not change significantly. It was considered that changes in the parameters after cecectomy may have resulted from lowered digestion and enhancement of propulsive activity in the gastrointestinal tract.

Animals↗

Functional role of lumbar sympathetic nerves and supraspinal mechanism in the defecation reflex of the cat.

The role of the lumbar sympathetic nerves and supraspinal mechanism in the defecation reflex was investigated in 30 adult cats and 6 kittens. One or two propulsive contractions, whose mean pressure evoked was more than about 90 cmH2O (adult cats) and 50 cmH2O (kittens), were induced in the rectum of all animals by rectal distension. These propulsive contractions could be generated at the descending and the transverse colons. The removal of the supraspinal influence by spinal transection at T13 or removal of pelvic afferents to the supraspinal center by spinal transection at L abolished the propulsive contractions. Successive lumbar sympathectomy restored the contractions. Lumbar sympathectomy and the successive removal of the supraspinal influence did not affect the propulsive contractions. In both cases, the final exclusion of the sacral segments by pithing of the spinal cord abolished the propulsive contractions. These results suggest that the sacral excitatory reflex mediated via pelvic nerves and the lumbar inhibitory reflex mediated via lumbar sympathetic nerves can function during rectal distension in spinal cats and that the lumbar inhibitory reflex is suppressed by the supraspinal sympathetic inhibitory reflex activated by pelvic afferents in intact cats, as in guinea pigs, resulting in propulsive contractions.

Afferent Pathways↗

Enterocele revealed by simultaneous evacuation proctography and peritoneography: does "defecation block" exist?

OBJECTIVE: Pelvic floor weakness may allow prolapse of the bowel into the rectogenital space, forming an enterocele. Enteroceles are believed to obstruct defecation by rectal compression and are therefore considered an abnormal finding on evacuation proctography. With a technique combine evacuation proctography and peritoneography, we prospectively studied constipated patients to reveal the pelvic peritoneal recesses during evacuation and to determine if enterocele actually impairs rectal emptying. SUBJECTS AND METHODS: Fifty constipated patients were studied prospectively, Using 20 ml of water-soluble contrast medium, we performed peritoneography, then evacuation protography with 120 ml of intrarectal paste. Lateral evacuation and posteroanterior stress views were analyzed by computerized video capture. Anatomic features and functional measurements of rectal emptying were noted. Posteroanterior views were compared with views in 31 subjects undergoing peritoneography for investigation of groin pain. RESULTS: Technical failure in three patients left 47 for analysis. A deep rectogenital pouch was seen in 36 patients (77%). Of these, 12 (58%) contained viscera that formed an enterocele, but the remaining 15 patients (42%) showed no visceral filling. Most pouches were apparent only during straining (31 cases, 86%). Peritoneal descent was greater than in controls (p < .0001), of whom only three had small rectogenital pouches. Patients with enterocele were compared with those who had a rectogenital pouch but no visceral filling and those who had no pouch. Standard anatomic measurements by evacuation proctography were not significantly different, but patients with enterocele evacuated more rapidly (p = .008) and completely (p = .021) than did the other two groups. CONCLUSION: Combined evacuation proctography and peritoneography is a new technique to diagnose pelvic hernias that occur during evacuation. This technique has shown that a deep rectogenital pouch is common in constipated patients and that just over half such pouches fill with viscera. However, because an enterocele does not impair rectal evacuation, this proctographic finding should be interpreted with caution.

Adolescent↗

Exfoliation of the epidermal cells and defecation by amphibian larvae in response to coelomic fluid and lysenin from the earthworm Eisenia foetida.

Coelomic fluid (CF) and lysenin from the earthworm Eisenia foetida induced heavy epidermal exfoliation in the larvae of Bufo japonicus formosus at developmental stages from hatching (stage 22) to operculum completion (stage 34). In experiments with Xenopus laevis, we observed that exfoliated cells were not stained by trypan blue. Thus, it appeared that these cells were still alive. It is likely, therefore, that both CF and lysenin might disrupt the adhesion between epidermal cells of larvae prior to stage 34. Since it is known that lysenin exerts its toxic effects through its specific binding to sphingomyelin (SM), SM might be involved in such adhesion. This hypothesis was supported by the observations that CF and lysenin which had been incubated with SM-liposomes lost their exfoliative activity. In larvae after stage 34, the mechanism of adhesion between epidermal cells seemed to change and the adhesion was no longer disrupted by CF and lysenin. In larvae at around stage 34, a collagen layer started to form beneath the basement membrane of the epidermis. Furthermore, larvae at around this stage started to eat solid food. The developing collagen layer and food intake might be related indirectly to the chemical change in epidermal adhesion. The induction of exfoliation by CF and lysenin was also observed in other amphibian species. In Bufo larvae, defecation was induced both by CF and by lysenin but this effect was independent of exfoliation.

Amphibians↗

Role of the sigmoid colon in the defecation mechanism with evidence of sigmoido-anal inhibitory and ano-sigmoid excitatory reflex.

In spite of voluminous literature that has been written on defecation, the exact mechanism has not yet been fully cleared up. The current study investigated the effect of sigmoid colon (SC) distension on anal motile activity and of anal distension on SC motility. Sixteen healthy volunteers (age 36.2 +/- 11.6 SD years, 10 men) were studied. The SC was distended by a balloon in 10 ml increments of CO2, and the anal, rectal and SC pressure response was recorded before and after their individual anesthetization. The anal, rectal and SC pressure response to anal distension in increments of 2 ml of CO2 was also registered. SC distension with big volumes (mean 86.2 +/- 1.9 ml) effected a SC pressure increase (p<0.05) and no rectal pressure response (p>0.05); the balloon was expelled to the exterior. Distension of the anesthetized SC caused no SC, rectal or anal pressure response (p>0.05, p>0.05, p>0.05, respectively); the response returned after the anesthetic effect had waned. SC distension while the rectum had been anesthetized, affected a significant SC pressure rise as well as an anal pressure decrease and balloon expulsion to the exterior. Anal balloon distension produced a significant pressure rise of the SC (p<0.001) and rectum (p<0.01). Distension of the anesthetized rectal neck (anal canal) caused no SC or rectal pressure response (p>0.05, p>0.05, respectively); response returned after the anesthetic effect had disappeared. SC distension appears to effect anal dilatation while anal distension causes SC contraction. This reciprocal action is suggested to be reflex and mediated through the "sigmoido-anal inhibitory reflex" and the "ano-sigmoid excitatory reflex". These 2 reflexes are believed to keep the SC contracting and the rectal neck dilated until complete SC evacuation occurs. The study seemingly negates the role of rectal distension as a prerequisite for balloon expulsion.

Adult↗