This work has tried to provide better insight in some pathophysiological factors involved in functional dyspepsia. We have identified several experimental evidences supporting the hypothesis that activation of transducers of wall tension at the level the proximal stomach might be the key to the genesis of at least some of the symptoms. One of the mechanisms by which this activation may be enhanced in patients is the presence of defective accommodation of the proximal stomach in response to a meal. This abnormality was present in a large subgroup of patients and was associated to the presence of early satiety. Pharmacological modulation of the gastric wall tension resulted in concomitant changes in symptom severity, both in health and in functional dyspepsia patients. Special attention has been given to provide the clinician with better tools to investigate his patient, in the perspective of the prescription of a treatment aimed at restoring a defective mechanism. / Ce travail a tenté d'améliorer la compréhension de certains mécanismes physiopathologiques de la dyspepsie fonctionnelle. Nous avons identifié plusieurs arguments expérimentaux soutenant l'hypothèse disant que c'est l'activation de mécanorécepteurs sensibles à la tension pariétale qui est reponsable d'au moins un des symptômes de l'affection. Un des mécanismes par lesquels cette activation peut accrue chez les patients est la présence d'un défaut de l'accommodation gastrique post-prandiale. Cette anomalie a été retrouvée dans une large proportion des patients et est associée à la présence de satiété précoce. Les modifications du tonus gastrique ont résulté dans de modifications concomitantes des symptômes aussi bien chez les volontaires que chez les patients atteints de dyspepsie fonctionnelle.Une attention particulière a été portée sur le développement de nouveaux outils permettant de caractériser les patients dans la perspective de la prescription d'un traitement visant à corriger un mécanisme défectueux.

This work has tried to provide better insight in some pathophysiological factors involved in functional dyspepsia. We have identified several experimental evidences supporting the hypothesis that activation of transducers of wall tension at the level the proximal stomach might be the key to the genesis of at least some of the symptoms. One of the mechanisms by which this activation may be enhanced in patients is the presence of defective accommodation of the proximal stomach in response to a meal. This abnormality was present in a large subgroup of patients and was associated to the presence of early satiety. Pharmacological modulation of the gastric wall tension resulted in concomitant changes in symptom severity, both in health and in functional dyspepsia patients. Special attention has been given to provide the clinician with better tools to investigate his patient, in the perspective of the prescription of a treatment aimed at restoring a defective mechanism. / Ce travail a tenté d'améliorer la compréhension de certains mécanismes physiopathologiques de la dyspepsie fonctionnelle. Nous avons identifié plusieurs arguments expérimentaux soutenant l'hypothèse disant que c'est l'activation de mécanorécepteurs sensibles à la tension pariétale qui est reponsable d'au moins un des symptômes de l'affection. Un des mécanismes par lesquels cette activation peut accrue chez les patients est la présence d'un défaut de l'accommodation gastrique post-prandiale. Cette anomalie a été retrouvée dans une large proportion des patients et est associée à la présence de satiété précoce. Les modifications du tonus gastrique ont résulté dans de modifications concomitantes des symptômes aussi bien chez les volontaires que chez les patients atteints de dyspepsie fonctionnelle.Une attention particulière a été portée sur le développement de nouveaux outils permettant de caractériser les patients dans la perspective de la prescription d'un traitement visant à corriger un mécanisme défectueux.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O tratamento cirÃrgico da doenÃa hemorroidÃria pela Anopexia MecÃnica (AM), utilizando grampeador circular PPH de 33mm (Ethicon EndoSurgery) pode estar relacionado a lesÃo esfincteriana perianal, com repercussÃo no padrÃo evacuatÃrio. O objetivo deste estudo à avaliar a sensibilidade e complacÃncia retal em pacientes submetidos a esta tÃcnica operatÃria. Foram estudados 10 pacientes portadores de hemorrÃidas grau III ou IV sintomÃticas. Todos os pacientes foram avaliados prÃ-operatoriamante utilizando-se um barostato (Visceral Stimulator; Synetics Medical), com base em dois protocolos de pesquisa da sensibilidade retal: um contÃnuo (Ramp Test) e outro aleatÃrio (Random test), nos quais foram aferidas as diferentes reaÃÃes dos pacientes frente à distensÃo volumÃtrica de um balÃo retal sob controle de um "software" (Polygram for Windows; Medtronic), o que permitiu a reprodutibilidade do mÃtodo no pÃs-operatÃrio. Foram observadas a sensaÃÃo retal inicial (1a. sensaÃÃo), a sensibilidade evacuatÃria (2a. sensaÃÃo) e a sensibilidade a dor (3a. sensaÃÃo). ApÃs cirurgia os pacientes foram reavaliados ao final de 2, 4 e 6 meses. Utilizou-se um grupo controle de 10 pacientes portadores de doenÃa pilonidal sacro-coccÃgea, submetidos ao mesmo protocolo de avaliaÃÃo no prà e pÃs-operatÃrio, diferenciando-os do grupo cirÃrgico pela nÃo realizaÃÃo da anopexia mecÃnica. Foram aplicados os testes estatÃsticos de Pearson e t-student para a anÃlise dos estatÃstica dos resultados. Observou-se diminuiÃÃo dos valores de complacÃncia e sensibilidade retal ao final de 2 meses de pÃs-operatÃrio no grupo submetido a AM, para todas as sensaÃÃes pesquisadas, em ambos os protocolos de insuflaÃÃo do barostato. NÃo se observou diferenÃa entre a complacÃncia e sensibilidade retal observada nas avaliaÃÃes prÃ-operatÃria e aos quatro e seis meses no grupo submetido a AM, bem como em nenhuma das avaliaÃÃes realizadas no grupo controle. Conclui-se que a Anopexia MecÃnica causa uma diminuiÃÃo transitÃria da complacÃncia e sensibilidade retal aos dois meses de pÃs-operatÃrio, valores estes que se recuperam a partir do quarto mÃs pÃs-operatÃrio. / Post-graduation Course in Surgery (Strictu Sensu), Departament of Surgery, Medicine School, Federal University of Cearà (Master in Surgery Degree). 2005, September. Professor: Prof. Dr. Lusmar Veras Rodrigues Surgical treatment of haemorrhoids by Stapled Anopexy (SA), using a circular stapler PPH - 33mm (Ethicon EndoSurgery) may damage perianal muscle fibers, with changes In defecation pattern. The aim of this study was to evaluate rectal compliance and sensitivity in patients treated by SA. Ten patients with grade III or IV sintomatic haemorrhoids were elegible for this study. All patients were studied before surgery with a barostat (Visceral Stimulator; Synetics Medical), using two research protocols for rectal sensitivity: a continuous one (Ramp Test) and another one in steps (Random test), that could record patient's perception to volumetric distention of a rectal baloon, controled by a software (Polygram for Windows, Medtronic). This software made the method reproductible to all patients in the post-operative period. The barostat was able to record the first rectal sensation (1st. sensation), urge to defecate (2nd. sensation) and rectal pain (3rd. sensation). Patients were studied following the same protocol at two, four and six months after surgery. A control group of ten patients with pilonidal sinus disease was submitted to the same protocol, except for stapled anopexy. Statistical analysis was acomplished using Pearson and Student's t test. The study found a decrease in retal compliance and sensitivity of patients treated by stapled anopexy, during the second post-operative month evaluation, for all recorded sensations, to all distension protocols. There was no difference in rectal compliance and sensitivity between pre-operative and post-operative at four and six months evaluations for patients treated by stapled anopexy. There was no difference in rectal compliance and sensitivity for any patient in control group, for any sensation recordered, using any distension protocol. The conclusion was that stapled anopexy caused a transient decrease in rectal compliance and sensitivity at the second postoperative month, that returned to normal values at the fourth post-operative month.

Recent studies suggest that patients identified by the Rome III criteria for functional constipation (FC) and irritable bowel syndrome with constipation (IBS-C) are not distinct groups. Previous studies have shown that patients with IBS-C exhibit no or limited 5-HT response to meal ingestion, with plasma concentrations remaining similar to those under fasting conditions. The aim of this study was to determine whether patients with FC show a similar 5-HT response to meal ingestion as patients with IBS-C, and to investigate any relationship to gastrointestinal transit and visceral sensitivity. 23 female IBS-C patients, 11 female FC patients and 23 healthy female volunteers (HV) were recruited. Platelet depleted plasma 5-HT concentrations were measured under fasting (2hrs) and fed (4hrs) conditions. Within 2 weeks, oro-caecal (hydrogen breath test) and colonic (radio-opaque markers followed by X-ray) transit, along with rectal sensitivity (barostat) were determined. The main findings of the study are: 1. The FC patients had no 5-HT response to meal ingestion, as previously seen in patients with IBS-C, compared with healthy volunteers. 2. Patients with FC had abdominal and bowel movement associated symptoms as well as delayed colonic transit (whole gut transit), similar to that seen in IBS-C compared with healthy volunteers. 3. The mean pain threshold in patients with FC was similar to that seen in healthy volunteers, with more patients with hyposensitivity or insensitivity in this group compared with IBS-C and no patients with hypersensitivity. 4. Patients with FC had a shift towards higher fasting and postprandial PDP 5-HT levels, unlike patients with IBS-C, compared to healthy volunteers.This study show that based on symptoms, IBS-C and FC patients have more similarities than differences. However, although patients with FC had a similar 5-HT response to a test meal, they had different fasting 5-HT levels and some different physiological findings on assessment of visceral sensitivity with barostat.