Effect of bowel cleansing on colonic transit in constipation due to slow transit or evacuation disorder

Radiopaque marker colonic transit study in the pediatric population BSPGHAN Motility Working Group consensus statement

Functional constipation (FC) is a common condition in childhood in the United Kingdom and worldwide. Various radiological approaches have been established for diagnostic purposes. The radiopaque marker study (ROMS) is universally accepted and used to assess colonic transit time (CTT) in children with FC. Despite being widely used, there is a lack of standardization with various technical protocols, reproducibility of different populations, the purpose for using investigation, variance in the number of markers used, the amount of study days and calculations, the need to empty the colon before performing the test, and whether to perform on medication or off, or the use of specific diets. As part of the British Society of Paediatric Gastroenterology, Hepatology and Nutrition (BSPGHAN) motility working group (MWG), we decided to explore further into the evidence, in order to provide guidance regarding the use of ROMS in dealing with FC in the pediatric population.

A Flexible Implant for Multi-Day Monitoring of Colon Segment Activity

Monitoring of colon activity is currently limited to tethered systems like anorectal manometry. These systems have significant drawbacks, but fundamentally limit the observation time of colon activity, reducing the likelihood of detecting specific clinical events. While significant technological advancement has been directed to mobile sensor capsules, this work describes the development and feasibility of a stationary sensor for describing the coordinated activity between neighboring segments of the colon. Unlike wireless capsules, this device remains in position and measures propagating pressure waves and impedances between colon segments to describe activity and motility. This low-power, flexible, wireless sensor-the colon monitor to capture activity (ColoMOCA) was validated in situ and in vivo over seven days of implantation. The ColoMOCA diameter was similar to common endoscopes to allow for minimally invasive diagnostic placement. The ColoMOCA included two pressure sensors, and three impedance-sensing electrodes arranged to describe the differential pressures and motility between adjacent colon segments. To prevent damage after placement in the colon, the ColoMOCA was fabricated with a flexible polyimide circuit board and a silicone rubber housing. The resulting device was highly flexible and suitable for surgical attachment to the colon wall. In vivo testing performed in eleven animals demonstrated suitability of both short term (less than 3 hours) and 7-day implantations. Data collected wirelessly from animal experiments demonstrated the ColoMOCA described colon activity similarly to wired catheters and allowed untethered, conscious monitoring of organ behavior.

Bowel transit studies in children: evidence base, role and practicalities

Constipation is common in children and adults with varied worldwide prevalence. The majority of children have functional constipation as defined by Rome clinical criteria and respond favourably to standard medical therapy; up to one-third can develop difficult-to-treat constipation requiring investigation and specialist treatment. Colon function tests aim to assess the neuromuscular integrity, the movement of faeces across the colon and evaluate/predict response to the therapy. The 'ideal' test should be practical, non-invasive, widely available and cost-effective. None of the available diagnostic tools is designed to provide a comprehensive assessment of colon function and clinicians often have to combine more than one test to answer different questions. In this review, we aim to assess the strengths and limitations of the commonly available diagnostic investigations (radiopaque marker studies, scintigraphy, wireless motility capsule and colonic manometry) used to assess colon transit in children and to provide guidance on the most appropriate test for particular clinical settings.

The effect of colonic tissue electrical stimulation and celiac branch of the abdominal vagus nerve neuromodulation on colonic motility in anesthetized pigs

BACKGROUND

Knowledge on optimal electrical stimulation (ES) modalities and region-specific functional effects of colonic neuromodulation is lacking. We aimed to map the regional colonic motility in response to ES of (a) the colonic tissue and (b) celiac branch of the abdominal vagus nerve (CBVN) in an anesthetized porcine model.

METHODS

In male Yucatan pigs, direct ES (10 Hz, 2 ms, 15 mA) of proximal (pC), transverse (tC), or distal (dC) colon was done using planar flexible multi-electrode array panels and CBVN ES (2 Hz, 0.3-4 ms, 5 mA) using pulse train (PT), continuous (10 min), or square-wave (SW) modalities, with or without afferent nerve block (200 Hz, 0.1 ms, 2 mA). The regional luminal manometric changes were quantified as area under the curve of contractions (AUC) and luminal pressure maps generated. Contractions frequency power spectral analysis was performed. Contraction propagation was assessed using video animation of motility changes.

KEY RESULTS

Direct colon ES caused visible local circular (pC, tC) or longitudinal (dC) muscle contractions and increased luminal pressure AUC in pC, tC, and dC (143.0 ± 40.7%, 135.8 ± 59.7%, and 142.0 ± 62%, respectively). The colon displayed prominent phasic pressure frequencies ranging from 1 to 12 cpm. Direct pC and tC ES increased the dominant contraction frequency band (1-6 cpm) power locally. Pulse train CBVN ES (2 Hz, 4 ms, 5 mA) triggered pancolonic contractions, reduced by concurrent afferent block. Colon contractions propagated both orally and aborally in short distances.

CONCLUSION AND INFERENCES

In anesthetized pigs, the dominant contraction frequency band is 1-6 cpm. Direct colonic ES causes primarily local contractions. The CBVN ES-induced pancolonic contractions involve central neural network.

Mechanisms, Evaluation, and Management of Chronic Constipation

With a worldwide prevalence of 15%, chronic constipation is one of the most frequent gastrointestinal diagnoses made in ambulatory medicine clinics, and is a common source cause for referrals to gastroenterologists and colorectal surgeons in the United States. Symptoms vary among patients; straining, incomplete evacuation, and a sense of anorectal blockage are just as important as decreased stool frequency. Chronic constipation is either a primary disorder (such as normal transit, slow transit, or defecatory disorders) or a secondary one (due to medications or, in rare cases, anatomic alterations). Colonic sensorimotor disturbances and pelvic floor dysfunction (such as defecatory disorders) are the most widely recognized pathogenic mechanisms. Guided by efficacy and cost, management of constipation should begin with dietary fiber supplementation and stimulant and/or osmotic laxatives, as appropriate, followed, if necessary, by intestinal secretagogues and/or prokinetic agents. Peripherally acting μ-opiate antagonists are another option for opioid-induced constipation. Anorectal tests to evaluate for defecatory disorders should be performed in patients who do not respond to over-the-counter agents. Colonic transit, followed if necessary with assessment of colonic motility with manometry and/or a barostat, can identify colonic dysmotility. Defecatory disorders often respond to biofeedback therapy. For specific patients, slow-transit constipation may necessitate a colectomy. No studies have compared inexpensive laxatives with newer drugs with different mechanisms. We review the mechanisms, evaluation, and management of chronic constipation. We discuss the importance of meticulous analyses of patient history and physical examination, advantages and disadvantages of diagnostic testing, guidance for individualized treatment, and management of medically refractory patients.

Management of functional constipation in children and adults

Functional constipation is common in children and adults worldwide. Functional constipation shows similarities in children and adults, but important differences also exist regarding epidemiology, symptomatology, pathophysiology, diagnostic workup and therapeutic management. In children, the approach focuses on the behavioural nature of the disorder and the initial therapeutic steps involve toilet training and laxatives. In adults, management focuses on excluding an underlying cause and differentiating between different subtypes of functional constipation - normal transit, slow transit or an evacuation disorder - which has important therapeutic consequences. Treatment of adult functional constipation involves lifestyle interventions, pelvic floor interventions (in the presence of a rectal evacuation disorder) and pharmacological therapy. When conventional treatments fail, children and adults are considered to have intractable functional constipation, a troublesome and distressing condition. Intractable constipation is managed with a stepwise approach and in rare cases requires surgical interventions such as antegrade continence enemas in children or colectomy procedures for adults. New drugs, including prokinetic and prosecretory agents, and surgical strategies, such as sacral nerve stimulation, have the potential to improve the management of children and adults with intractable functional constipation.

A new approach in bowel preparation before colonoscopy in patients with constipation: A prospective, randomized, investigator-blinded trial

OBJECTIVE

Enema administration in the morning of routine colonoscopy is known to be useless. However, the potential bowel cleansing effects of distal colon emptying with enema prior to purgatives are not known. The aim of this study is to investigate the effects of enema use before purgatives in preparation for colonoscopy.

MATERIAL AND METHODS

Two hundred twenty-seven patients were randomly assigned into three groups; enema before purgative use, enema after purgative use, and no enema. Patients were compared in terms of age, sex, BMI, Rome III constipation criteria, history of abdominal surgery, tolerance to the preparation procedure, complications during preparation such as nausea, vomiting, headache and dizziness, cecal insertion time, total duration of colonoscopy, polyp determination rate and colonic cleansing based on the Boston Bowel Preparation Scale.

RESULTS

One hundred two (44.9%) patients were male and 125 (55.1%) female. The mean age and BMI was 55.4±11.8 years and 28.8±4.7, respectively. No difference was observed between the groups in terms of sex, age, or BMI. The number of fulfilled Rome criteria and of previous abdominal surgeries were significantly higher in females than in men. Right colon Boston Bowel Preparation Scale score was higher in the group using enemas before purgatives than the scores of other groups. This improvement was statistically significant in the female patient group with higher constipation rate.

CONCLUSIONS

Use of enemas before purgatives in patients with constipation significantly improves adequacy of right colon cleansing.

Effect of Bowel Cleansing on Colonic Transit Time Measurement in Children with Chronic Constipation

We evaluated the effect of bowel preparation on colonic transit time (CTT) measured by the radio-opaque marker test in children with constipation. All children underwent 2 radio-opaque marker-CTT tests, both in cleansed and uncleansed bowel state. Our findings confirm that the state of colonic fecal filling may significantly influence CTT.

Partially hydrolyzed guar gum accelerates colonic transit time and improves symptoms in adults with chronic constipation

BACKGROUND AND AIM

Partially hydrolyzed guar gum (PHGG) is a water-soluble, non-gelling dietary fiber with a wide range of uses in clinical nutrition. The aim of this prospective study was to investigate the effect of guar gum on colonic transit time (CTT) and symptoms of chronic constipation.

METHODS

We enrolled patients fulfilling Rome III criteria for chronic constipation. CTT was measured before and at the end of treatment. After a 2-week run-in period, patients received 5 mg PHGG daily for 4 weeks. During study period, patients kept daily symptoms, stool and laxative usage diaries. They also recorded their symptom-related satisfaction weekly and treatment adverse events.

RESULTS

Forty-nine patients received treatment; 39 (80 %) completed the study. Treatment significantly reduced colon transit time, from 57.28 ± 39.25 to 45.63 ± 37.27 h (p = 0.026), a reduction more prominent in slow transit patients (from 85.50 ± 27.75 to 63.65 ± 38.11 h, p = 0.016). Overall, the weekly number of complete spontaneous and spontaneous bowel movements increased significantly (p < 0.001); the latter correlated significantly with the acceleration of CTT in the overall population and in slow transit patients (B = 0.382; p = 0.016 and B = 0.483; p = 0.023, respectively). In addition, the number of bowel movements with straining decreased (p < 0.001) and stool form improved (p < 0.001), while days with laxative intake and days with abdominal pain decreased (p = 0.001 and p = 0.027, respectively).

CONCLUSION

Four-week PHGG use accelerates colon transit time in patients with chronic constipation, especially in those with slow transit, and improves many of their symptoms including frequency of bowel movements.

Potential biomarkers

A "biomarker" (biological marker) is an indicator of a bodily function that can be objectively measured. A wide range of possible biomarkers for IBS have been considered but at present only gut transit measured using radio-isotope markers meet the criteria of reproducibility and availability. While barostat studies perform reasonably in expert centers, to do them reproducibly requires considerable effort and standardization. This makes them unsuitable for widespread use. However radio-isotope tests are expensive and of limited availability so the search for other more convenient markers including blood and stool tests is still an important goal for the future.

Empty colon: a pitfall in the assessment of colonic transit time

We report a misleading outcome of colonic transit time (CTT) assessment in an adolescent girl with functional constipation. We found prolonged total and right segmental CTT despite high doses of oral polyethylene glycol 4000 and repeated treatment with polyethylene glycol-electrolyte solution (Klean-Prep®) by nasogastric tube. A colonoscopy aiming at disimpaction of a possible faecal mass revealed an empty colon with dozens of radio-opaque markers adhered to the colonic wall. This report shows that the result of a CTT cannot be accepted blindly. Especially the clustering of many markers within narrow margins might point at entrapment of markers in mucus against the colonic wall.

Heightened colon motor activity measured by a wireless capsule in patients with constipation: relation to colon transit and IBS

Relationships of regional colonic motility to transit in health, constipation, and constipation-predominant irritable bowel syndrome (C-IBS) are poorly characterized. This study aimed to 1) characterize regional differences in colon pressure, 2) relate motor differences in constipation to colon transit, and 3) quantify the role of IBS in altered contractility with constipation. Colon pH and pressure were measured by wireless capsules in 53 healthy and 36 constipated subjects. Numbers of contractions >25 mmHg and areas under curves (AUC) were calculated for colon transit quartiles by time. Constipation was classified as normal transit (<59 h), moderate slow transit (STC) (59-100 h), and severe STC (>100 h). Twelve out of 36 constipated subjects had C-IBS; 24 had functional constipation. Numbers of contractions and AUCs increased from the first to the fourth quartile in health (P < 0.0001). Mean numbers of contractions in constipated subjects were similar to controls. Mean AUCs with normal transit (P = 0.01) and moderate STC (P = 0.004) but not severe STC (P = NS) were higher than healthy subjects. IBS was associated with greater mean numbers of contractions (P = 0.05) and AUCs (P = 0.0006) vs. controls independent of transit. Numbers of contractions increased from the first to fourth quartiles in moderate STC, C-IBS, and functional constipation; AUCs increased from the first to fourth quartiles in all groups (all P < 0.05). In conclusion, colon pressure activity is greater distally than proximally in health. Constipated patients with normal or moderately delayed transit show increased motor activity that is partly explained by IBS. These findings emphasize differential effects on transit and motility in different constipation subtypes.

Rectal fecal impaction treatment in childhood constipation: enemas versus high doses oral PEG

OBJECTIVE

We hypothesized that enemas and polyethylene glycol (PEG) would be equally effective in treating rectal fecal impaction (RFI) but enemas would be less well tolerated and colonic transit time (CTT) would improve during disimpaction.

METHODS

Children (4-16 years) with functional constipation and RFI participated. One week before disimpaction, a rectal examination was performed, symptoms of constipation were recorded, and the first CTT measurement was started. If RFI was determined, then patients were assigned randomly to receive enemas once daily or PEG (1.5 g/kg per day) for 6 consecutive days. During this period, the second CTT measurement was started and a child's behavior questionnaire was administered. Successful rectal disimpaction, defecation and fecal incontinence frequencies, occurrence of abdominal pain and watery stools, CTTs (before and after disimpaction), and behavior scores were assessed.

RESULTS

Ninety-five patients were eligible, of whom 90 participated (male, n = 60; mean age: 7.5 +/- 2.8 years). Forty-six patients received enemas and 44 PEG, with 5 dropouts in each group. Successful disimpaction was achieved with enemas (80%) and PEG (68%; P = .28). Fecal incontinence and watery stools were reported more frequently with PEG (P < .01), but defecation frequency (P = .64), abdominal pain (P = .33), and behavior scores were comparable between groups. CTT normalized equally (P = .85) in the 2 groups.

CONCLUSION

Enemas and PEG were equally effective in treating RFI in children. Compared with enemas, PEG caused more fecal incontinence, with comparable behavior scores. The treatments should be considered equally as first-line therapy for RFI.

Clinical effects of colonic cleansing for general health promotion: a systematic review

The practice of colonic cleansing to promote general health and well-being continues to generate interest among the lay population. These practices are widely touted as adjuncts to improve vitality and as therapeutic modalities to minimize the symptoms, or prevent the actual development, of a variety of chronic disease states. The data supporting colonic cleansing and body "detoxification" have not been studied well in a systematic manner. This report describes a systematic review of the published literature of both the traditional and complementary and alternative medicine arenas that was performed in an attempt to qualify and quantify the value of colonic cleansing. The investigators concluded that there are no methodologically rigorous controlled trials of colonic cleansing to support the practice for general health promotion. Conversely, there are multiple case reports and case series that describe the adverse effects of colonic cleansing. The practice of colonic cleansing to improve or promote general health is not supported in the published literature and cannot be recommended at this time.

Colonic lavage with two polyethylene glycol solutions prior to colonoscopy makes no difference: a prospective randomized controlled trial

OBJECTIVE

It is suggested that bowel preparations for colonoscopy are easier to tolerate when a smaller volume of solution with a more pleasant taste is used. The aim of this study was to establish equivalence between a 3-l sulphate-free polyethylene glycol solution (SF-PEG) and a 4-l PEG solution in effectiveness, patients' acceptability and tolerability.

MATERIAL AND METHODS

The study comprised 110 patients scheduled for elective colonoscopy and randomized to receive either SF-PEG or PEG. Before colonoscopy, the patients completed a questionnaire on stool frequency, medication, concomitant diseases, the amount of solution ingested, willingness to re-take it, volume of other fluid taken and tolerance of bowel preparation, taste of the laxative and occurrence of abdominal cramps. Three experienced endoscopists, blinded to the type of preparation, assigned bowel-cleansing scores using a validated 5-point scale to assess cleansing effect.

RESULTS

Data were available for 102 patients (44 M (40%), mean age 53 years, range 23-83 years). No significant differences were found in cleansing the rectosigmoid (p = 0.71) or complete colon (p = 0.79). Diverticulosis, constipation, gender and body mass index (BMI) did not influence cleansing. There was no significant difference in compliance between the two groups (p = 0.61). No differences were found for tolerance, taste and abdominal cramps. Patients who received SF-PEG had a preference for the same preparation next time in comparison with patients who had PEG cleansing (17 (33%) versus 4 (8%), respectively) (p = 0.03).

CONCLUSIONS

Both preparations are comparable in their cleansing effect and toleration. However, patients prefer cleansing with a smaller volume of solution. Improving the acceptability of colonic preparation could improve willingness to undergo colonoscopies in the future.

In patients with slow transit constipation, the pattern of colonic transit delay does not differentiate between those with and without impaired rectal evacuation

BACKGROUND

Severe constipation may be subclassified on the basis of speed of colonic transit and efficacy of rectal evacuation. It is hypothesized that rectal evacuatory disorder (RED) may be associated with a secondary transit delay.

OBJECTIVES

To determine whether scintigraphy can discriminate between slow transit constipation (STC) with or without coexistent RED on the basis of progression of isotope throughout the colon and by analyses of specific regions of interest.

METHODS

One hundred ninety-six patients with STC (radio-opaque marker study) were subclassified according to results of proctography into those with a RED (STC-RED N = 30) or normal (STC-ONLY N = 41) evacuation. Patients subsequently underwent colonic scintigraphy. Distribution of generalized or left-sided patterns of colonic transit was assessed. Severities of transit delay and regional transit at specific time points were also evaluated.

RESULTS

Time-activity curves and severity of global transit delay were similar between groups as were the incidences of generalized and left-sided patterns of delay. Percentage of radioisotope retention in the right colon at 18 h was higher for the STC-ONLY group (P < 0.05), but this was poorly discriminative. No differences were observed for the percentage of radioisotope retained in the left colon at later scans.

CONCLUSIONS

Global and regional assessment of colonic transit by scintigraphy failed to discriminate between patients with STC with or without coexistent RED. Thus, RED is not associated with a specific pattern of transit delay and scintigraphy alone cannot predict the presence or absence of RED, knowledge of which is important for management.

Segmental colonic transit studies: comparison of a radiological and a scintigraphic method

OBJECTIVE

Colonic transit studies are used to diagnose slow transit constipation (STC) and to evaluate segmental colonic transit before segmental or subtotal colectomy. The aim of the study was to compare a single X-ray radio-opaque marker method with a scintigraphic technique to assess total and segmental colonic transit in patients with STC.

METHOD

Thirty-one female patients (median age 46 years) with severe constipation and a prolonged or borderline prolonged colonic transit time on radio-opaque marker study were included in the study. They were subsequently investigated with (111)Indium-DTPA colonic transit scintigraphy, with a median time between the investigations of 4(range 1-27) months. Normal values of healthy female controls were used for comparison.

RESULTS

There was no difference between the two methods in terms of prolonged or normal total colonic transit time. Twenty-nine of 31 female patients had a prolonged transit time only in one or two segments on the marker study. On scintigraphy, the transit time was prolonged for patients in the left (P < 0.05 to P < 0.001), but not in the right colon. With respect to prolonged or normal segmental transit time, there was a significant difference between the two methods only in the descending colon (P = 0.02). However, the results varied considerably for individual patients.

CONCLUSION

Segmental colonic delay was a common finding. The two methods gave similar results for groups of patients, except in the descending colon. The variation of the results for individuals suggests that a repeated transit test may improve the assessment of total and segmental transit.

A controlled, randomized, double-blind trial to evaluate the effect of a supplement of cocoa husk that is rich in dietary fiber on colonic transit in constipated pediatric patients

OBJECTIVE

Although a diet that is rich in fiber is widely recommended for preventing and treating constipation, the efficacy of fiber supplements have not been tested sufficiently in children. Our aim with this pilot study was to evaluate if fiber supplementation is beneficial for the treatment of children with idiopathic chronic constipation.

METHODS

Using a parallel, randomized, double-blind, controlled trial, we conducted an interventional study to evaluate the efficacy of a supplement of cocoa husk rich in dietary fiber on intestinal transit time and other indices of constipation in children with constipation. After screening, the patients were randomly allocated to receive, for a period of 4 weeks, either a cocoa husk supplement or placebo plus standardized toilet training procedures. Before and after 4 weeks of treatment, we (1) performed anthropometry, a physical examination, and routine laboratory measurements, (2) determined total and segmental colonic transit time, (3) evaluated bowel movement habits and stool consistency using a diary, and (4) received a subjective evaluation from the parents regarding the efficacy of the treatment. The main variable for verifying the efficacy of the treatment was the total colonic transit time.

RESULTS

Fifty-six chronically constipated children were randomly assigned into the study, but only 48 children completed it. These children, who were aged between 3 and 10 years, had a diagnosis of chronic idiopathic constipation. With respect to total, partial colon, and rectum transit time, there seemed to be a trend, although statistically nonsignificant, toward faster transit times in the cocoa husk group than in the placebo group. When we analyzed the evolution of the intestinal transit time throughout the study of children whose total basal intestinal transit time was > 50th percentile, significant differences were observed between the groups. The total transit time decreased by 45.4 +/- 38.4 hours in the cocoa husk group and by 8.7 +/- 28.9 hours in the placebo group (-38.1 hours). In the case of the right colon, changes in transit time also were significant between groups. Mean changes tended toward faster transit times in the left colon and the rectum, although the differences were not statistically significant. The children who received cocoa husk supplements tended to increase the number of bowel movements by more than that of the children of the placebo group. We also observed a reduction in the percentage of patients who reported hard stools (hard scybalous or pebble-like stools), although this reduction was significantly greater in the cocoa husk group. At the end of the intervention, 41.7% and 75.0% of the patients who received cocoa husk supplementation or placebo, respectively, reported having hard stools. Moreover, a significantly higher number of children (or their parents) reported a subjective improvement in stool consistency. No significant adverse effects were reported during the study.

CONCLUSIONS

This study confirms the beneficial effect of a supplement of cocoa husk that is rich in dietary fiber on chronic idiopathic constipation in children. These benefits seem to be more evident in pediatric constipated patients with slow colonic transit time.

Outlet type constipation in Parkinson's disease: results of botulinum toxin treatment

BACKGROUND

Constipation is one of the most common autonomic dysfunctions observed in Parkinson's disease.

AIM

To investigate the efficacy of injections of botulinum toxin in improving rectal emptying in these patients.

METHODS

Eighteen Parkinson's disease patients with outlet constipation were included in the study. The patients were treated with type A botulinum toxin, injected into two sites on either side of the puborectalis muscle under ultrasonographic guidance.

RESULTS

Symptomatic improvement was noted in 10 patients, at 2 months evaluation. In these subjects, anorectal manometry demonstrated decreased tone during straining from 96.2 +/- 17.1 to 45.9 +/- 16.2 mmHg at 1 month evaluation (P = 0.00001) and to 56.1 +/- 10.7 mmHg at 2 months (P = 0.00001). Pressure during straining was lower than resting anal pressure at the same times in all patients. Defecography after the treatment showed improvement in anorectal angle during straining, which increased from 99.1 +/- 8.4 degrees to 121.7 +/- 12.7 degrees (P = 0.00001) at 2 months.

CONCLUSIONS

Botulinum toxin injections may be a useful treatment for Parkinson's disease patients affected by outlet-obstruction constipation. The treatment is safe and simple. However, because the effects of the toxin wear off within 3 months of administration, repeated injections could be necessary to maintain the clinical improvement.

Prognosis of constipation: clinical factors and colonic transit time

BACKGROUND

Measurement of colonic transit time (CTT) is sometimes used in the evaluation of patients with chronic constipation.

AIM

To investigate the relation between symptoms and CTT, and to assess the importance of symptoms and CTT in predicting outcome.

METHODS

Between 1995 and 2000, 169 consecutive patients (median age 8.4 years, 65% boys) fulfilling the criteria for constipation were enrolled. During the intervention and follow up period, all kept a diary to record symptoms. CTT was measured at entry to the study.

RESULTS

At entry, defecation frequency was lower in girls than in boys, while the frequency of encopresis episodes was higher in boys. CTT values were significantly higher in those with a low defecation frequency (< or =1/week) and a high frequency of encopresis (> or =2/day). However, 50% had CTT values within the normal range. Successful outcome occurred more often in those with a rectal impaction. CTT results <100 hours were not predictive of outcome. However, those with CTT >100 hours were less likely to have had a successful outcome.

CONCLUSION

The presence of a rectal impaction at presentation is associated with a better outcome at one year. A CTT >100 hours is associated with a poor outcome at one year.

Manometric techniques for the evaluation of colonic motor activity: current status

Colonic motility disorders are common conditions. However, our understanding of normal, and, consequently, pathological motor function of the colon remains limited, mainly due to the relative inaccessibility of this organ for study. Investigation of colonic motility may encompass one or more of the four separate components (myoelectric activity, phasic and tonic contractile activity and movement of intraluminal content) using electrophysiological, manometric or transit studies. Although transit studies provide the best 'functional' appreciation of colonic motor activity, and are the only techniques used in contemporary clinical practice, manometric methods are becoming increasingly popular, as they allow a direct study of colonic contractile activity over prolonged periods. To date, the majority of studies have been limited to the pelvic colon by a retrograde (per rectal) approach; however, recent technological advances have facilitated 'pan-colonic' investigation. This review concentrates on manometry of the human colon proximal to the sigmoid, and includes evaluation of both phasic and tonic motor activity, by utilization of perfused-tube and solid-state manometric catheters, and also the electronic barostat. Methodological techniques, experimental protocols and the analysis and interpretation of recorded data are critically explored, and a contemporary classification of colonic contractile activities is presented.

Rectal sensorimotor characteristics in female patients with idiopathic constipation with or without paradoxical sphincter contraction

Patients with chronic constipation fulfilling the Thompson criteria can show paradoxical sphincter contraction. Aim of this study was to evaluate rectal sensorimotor characteristics in patients with constipation with or without paradoxical sphincter contraction. Thirty female patients with chronic constipation and 22 female controls were investigated with anal manometry and rectal barostat. Paradoxical sphincter contraction was shown with manometry as a paradoxical increase of anal pressure during straining. Visceral sensitivity and compliance were tested by intermittent and continuous pressure-controlled distension. Patients were classified according to their sensations and compliance into normal, hypersensitive, reduced compliant, insensitive or excessive compliant rectum. Postprandial rectal response (PRR) and phasic volume events (PVEs) were registered for 1 h after a 600-kCal meal. Paradoxical sphincter contraction was found in 13 (43%) patients. In these patients, rectal sensitivity scores were higher (P = 0.045) than in patients without paradoxical contractions, but rectal compliance was not different. In 90% of patients an abnormal rectal sensitivity or compliance was found: excessively compliant in 35%, reduced compliant in 10%, hypersensitive in 27% and hyposensitive in 17%. Both patients with constipation (11%; P = 0.042) and controls (25%; P = 0.002) exhibited the presence of a postprandial rectal response. This response was not significantly different between idiopathic constipation, paradoxical sphincter contraction and controls. Patients with rectal hypersensitivity had lower response than other patients (P = 0.04). Patients with constipation had fewer basal PVEs compared controls (P = 0.03). Postprandial PVEs increased in both patients (P = 0.014) and controls (P < 0.001). Postprandial rectal response and PVE were not different in patients with or without paradoxical sphincter contraction. A total of 90% of female patients with idiopathic constipation show an abnormality in rectal sensation or compliance. The postprandial rectal response was comparable between patients with constipation and controls, however, PVEs were diminished. Patients with paradoxical sphincter contraction had higher rectal sensitivity but an unaltered compliance and postprandial rectal response. Future trials should investigate whether the classification of rectal abnormalities in patients with constipation has clinical importance.