Defecation mechanisms after proctocolectomy and ileal pouch-anal anastomosis in dogs

• Published in: International journal of colorectal disease Vol. 19; no. 3; pp. 228 - 233
• Main Authors: WILLIS, S, HÖLZL, F, WEIN, B, VON FELBERT, V, FACKELDEY, V, SCHUMPELICK, V
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01-05-2004; Berlin Springer Nature B.V
• Subjects: Anal Canal - diagnostic imaging; Animals; Biological and medical sciences; Defecation - physiology; Dogs; Electromyography; Gastroenterology. Liver. Pancreas. Abdomen; Gastrointestinal Motility; Manometry; Medical sciences; Motility; Proctocolectomy, Restorative; Radiography; Ileal pouch anal anastomosis; Fissipedia; Carnivora; Motility; Mechanism; Ileal pouch-anal anastomosis; Vertebrata; Mammalia; Treatment; Surgery; Animal; Gastroenterology; Rectum; Proctocolectomy; Colon; Dog; Defecation
• ISSN: 0179-1958; 1432-1262
• DOI: 10.1007/s00384-003-0540-x

The role of intrinsic pouch motility after ileal pouch-anal anastomosis (IPAA) during defecation is still speculative.
IPAA was performed in 12 dogs. Defecation mechanisms were evaluated by motility recordings during spontaneous defecation and during expulsion of an endoluminal balloon and by radiography with sequential sector-related gray scale analysis.
Spontaneous defecations appeared without significant changes in electrical or mechanical activity of the pouch. Sequential filling of the pouch led to defecation in only seven dogs while the others did not succeed in emptying their pouch even with maximal balloon inflation. Neither strain gauge measurements nor electromyography demonstrated peristaltic contractions of the pouch during defecation while sector-related gray scale analysis revealed strong contractions of the abdominal wall during pouch emptying.
Pouch emptying is independent of intrinsic pouch motility. The ileoanal pouch acts as a functionally passive reservoir, and its evacuation is initiated by a rise of the intra-abdominal pressure.