Ghislain Staumont

Evaluation of colonic sensory thresholds in IBS patients using a barostat. Definition of optimal conditions and comparison with healthy subjects.

To study the role of abnormal visceral perception in the pathophysiology of the irritable bowel syndrome (IBS), we evaluated colonic tone and visceral perception during intracolonic distension using a flaccid balloon connected to a computerized barostat and placed in the descending colon of IBS patients and healthy controls. In the first part of the study, basal colonic tone and response to pharmacological (neostigmine and glucagon) and physiological (1000-kcal meal) stimuli were recorded in nine IBS patients. Colonic tone increased by 72±27% after injection of neostigmine and decreased by 88±62% after glucagon. After the meal, the maximal increase in colonic tone was 76±31% with the total response to the meal lasting 109.7±32.0 min. In the second part of the study, symptomatic responses (discomfort and pain thresholds) and pressure variations were evaluated during two different methods of distension (stepwise and intermittent) in a randomized order in the nine IBS patients and six healthy controls. Each distension method was repeated twice in IBS patients to study reproducibility. In IBS patients, the mean discomfort threshold volume was 172±76 ml when using stepwise and 167±43 ml when using intermittent distension. The mean pain threshold volume was 250±25 ml when using stepwise and 211±22 ml when using intermittent distension, this difference being statistically significant (P<0.02). Discomfort and pain threshold volumes recorded during the first session of the same distension method were not different from those recorded during the second one. When comparing IBS patients to controls, the pain threshold was reached at a volume ≤300 ml in all IBS patients versus only one control when using stepwise distensions (P<0.001) and in all IBS patients versus no control when using intermittent distensions (P<0.001). Intracolonic pressure-volume curves were similar in patients and controls. In conclusion, isovolumic distension of the colon is a reproducible method of evaluating viscerosensitivity, which is significantly increased in IBS patients. This increased viscerosensitivity is not related to abnormal colonic compliance and may, alone or in combination with other colonic abnormalities, explain the symptoms of irritable bowel syndrome.

Octreotide increases thresholds of colonic visceral perception in IBS patients without modifying muscle tone.

Effects of octreotide (1.25 µg/kg subcutaneously) on colonic tone and visceral perception were evaluated in 10 IBS patients, using a barostat and compared to placebo in a double-blind crossover study. Colonic sensory thresholds were also studied in healthy controls for comparison with IBS patients. Colonic tone was reflected by variations in volume of the barostat balloon. Baseline volume was 117±38 ml and was not modified by placebo (122±40 ml) or octreotide (106±42 ml). After the meal, maximal decrease in balloon volume was 75±4% following placebo (P<0.001) beginning after 9±3 min and lasting 136±17 min. Following octreotide, the maximal decrease was 69±16% (NS vs placebo), after 10±3 min and lasting 140±22 min. In the second part, discomfort and pain thresholds were evaluated during isobaric distensions (4 mm Hg increments, 5-min duration, 5-min interval with return to pressure 0 between each). The pressure inducing discomfort was 21.2±5.9 mm Hg following placebo vs 29.6±6.6 mm Hg following octreotide (P<0.01). The pressure inducing pain was 24.8±7.3 mm Hg following placebo vs 33.2±7.3 mm Hg following octreotide (P<0.01). In healthy subjects, discomfort and pain were induced by colonic distensions at a mean intraballoon pressure of 32.7±5.8 mm Hg and 36.7±3.9 mm Hg, respectively. Compliance curves were not different following placebo and octreotide. Octreotide significantly increases thresholds for visceral perception in IBS patients without modifying compliance during distension nor colonic tone.

Effects of sennosides on colonic myoelectrical activity in man

The effects of sennosides on colonic myoelectrical activity were investigated in man. Spiking activity of the left and sigmoid colons was continuously recorded in seven constipated patients during two sessions from 5:00 PM to 9:00 am. Each patient received orally at 7:00pmon two consecutive days 30 mg of sennosides one day (sequence S) and placebo on the other (sequence P) in a random fashion. A significant (P<0.05) increase of peristaltic activity (migrating long spike bursts or MLSBs) after sennosides was observed between 1:00 and 7:00am,and a corresponding decrease between 7:00 and 9:00am.No change was noted in total short spike burst (SSB) activity or in SSBs characteristic of the rectosigmoid area. This study indicates that the main modification of colonic motility induced by sennosides was a stimulation of propulsive activity (MLSBs), which occurred between 6–12 hr after oral administration, the delay required for orocecal transit and metabolism of the drug.

Oral Prostaglandin E Analogues Induce Intestinal Migrating Motor Complexes After a Meal in Dogs Evidence for a Central Mechanism

The effects of oral, intravenous, and intracerebroventricular administration of synthetic derivatives of prostaglandins E1 (misoprostol) and E2 (enprostil) on postprandial gastrointestinal motility were investigated in dogs chronically fitted with strain gauge transducers on the antrum and the proximal and middle jejunum. Synthetic prostaglandin E analogues administered orally at a dose of 20-50 micrograms/kg 15 min before the meal did not modify the postprandial pattern of gastric contractions but suppressed the spontaneous postprandial irregular activity on the jejunum and induced a cyclic pattern of migrating motor complexes for 4-6 h after the meal. These postprandial migrating motor complexes induced by prostaglandin E were propagated between the two recording sites and had a period similar to that observed in the fasted state. However, the duration of phase 2 was significantly increased and the amplitude of the phase 3 decreased. This jejunal cyclic motor pattern was reproduced by administration of synthetic prostaglandin E derivatives either intravenously (4-10 micrograms/kg) 15 min before the meal or intracerebroventricularly (50 ng/kg) 1 h after the meal. The intestinal migrating motor complex activity observed after oral administration of synthetic prostaglandin E derivatives was abolished by the previous intracerebroventricular (40 micrograms/kg) but not intravenous (200 micrograms/kg) administration of SC-19220, a receptor antagonist of prostaglandin E. These results suggest that oral administration of synthetic prostaglandin E1 (misoprostol) or prostaglandin E2 (enprostil) analogues before a meal induces postprandial migrating motor complexes on the jejunum in dogs through a mechanism involving central prostaglandin receptors.

Sennosides and Human Colonic Motility

The effects of stimulant laxatives on colonic motility in man still remain controversial. Stimulation of peristalsis or a decrease of intraluminal pressure has been described manometrically after intraluminal administration of laxatives including senna. In contrast to manometry, electromyographic methods using an endoluminal probe enable continuous colonic motor recordings over a long colonic segment for at least 24 h, and consequently studies following the course of laxative effects after oral administration, the classical therapeutic route, are possible. Preliminary results using sennosides obtained with few subjects provide evidence for an increase in propulsive activity expressed as an increased number of migrating long-spike bursts in the left and sigmoid human colon. This motor colonic pattern seems to be a common feature in nonspecific or induced diarrhoea.

One-year outcome of haemorrhoidectomy: a prospective multicentre French study

An evaluation was performed of the 1‐year outcome of open haemorrhoidectomy (Milligan and Morgan alone or with posterior mucosal anoplasty [the Leopold Bellan procedure]).

Differences between jejunal myoelectric activity after a meal and during phase 2 of migrating motor complexes in healthy humans

Using an intraluminal probe with six pairs of annular electrodes, the myoelectric activity of the proximal jejunum was recorded during 48-hr sessions in 16 healthy volunteers receiving evening and noon meals (1000 kcal) and breakfast (400 kcal). In 10 subjects receiving no drug, the characteristics of the migrating motor complexes (period, duration of each phase, velocity of propagation of phase 3, duration of the postprandial disruption) varied markedly between subjects but were relatively constant from the first to the second day of recording. Single spike bursts propagated at a rate of 2–5 cm/sec, clusters of 3–10 spike bursts propagated at a rate of 0.5–1 cm/sec, and similar clusters recurring repetitively each 1.5–2 min were observed after the meals and very rarely in the fasted state during phase 2 of nocturnal migrating motor complexes. In six subjects, oral administration of codeine (50 mg) 1 hr before a meal induced migrating motor complexes in the postprandial state, with characteristics similar to that observed in the fasted state except a longer duration of phase 2. Single spike bursts and isolated and repetitive clusters of spike bursts were observed during phase 2 of the codeine-induced migrating motor complexes and after meals preceded by placebo, but very rarely during the phase 2 of nocturnal (fasted state) migrating motor complexes. It is concluded that the patterns of jejunal contractions consisting of propagated single spike bursts and isolated or repetitive spike bursts characterize the postprandial state in healthy humans and are dependent upon digesta flow.

Sphincter-sparing anal-fissure surgery: a 1-year prospective, observational, multicentre study of fissurectomy with anoplasty.

Aim  Internal sphincterotomy is the standard surgical treatment for chronic anal fissure, but is frequently complicated by anal incontinence. Fissurectomy is proposed as an alternative technique to avoid sphincter injury. We describe 1‐year outcomes of fissurectomy.

The outcome of fistulotomy for anal fistula at 1 year: a prospective multicentre French study

The study aimed to evaluate outcome at 1 year of one‐ and two‐stage fistulotomy for anal fistula in a large group of patients.

Recommandations pour la pratique clinique sur le traitement de la maladie hémorroïdaire

AVANT-PROPOS Ces recommandations pour la pratique clinique ont été élaborées conformément aux règles méthodologiques préconisées par l’Agence Nationale d’Accréditation et d’Evaluation en Santé, qui leur a attribué son label de qualité. Les conclusions et recommandations présentées dans ce document ont été rédigées, en toute indépendance, par le groupe de travail de ces recommandations pour la pratique clinique. Leur teneur n’engage en aucune manière la responsabilité de l’ANAES.