This section is from the book "Diseases Of The Intestines", by Max Einhorn. Also available from Amazon: Diseases Of The Intestines A Text-Book For Practitioners And Students Of Medicine.
Lavage of the bowel in a similar manner as performed in the stomach has been recommended by Boas 1 for diagnostic purposes. It is best performed in the lateral posture of the patient after an evacuation of the bowels. The same apparatus as for gastric lavage may be used here. The rectal tube, which represents the stomach tube employed in gastric lavage, is attached to a long piece of rubber tubing provided with a big funnel. The rectal tube is inserted as high up in the bowel as possible and then the water is poured in until the patient begins to feel some discomfort. As soon as this is the case the funnel is lowered and thus the water returns. The latter is now subjected to a thorough examination. Normally the returning water appears pretty clear or slightly turbid by the admixture of small particles of mucus, epithelial cells, and fecal matter. In catarrh of the large bowel a considerable quantity of mucus is found. Ulcerative processes accompanied by hemorrhages or by suppuration are often recognized by the admixture of either pus or blood in the wash-water. Occasionally exfoliated pieces of intestinal mucosa are found in the wash-water, and a microscopical examination of them may be of diagnostic importance.
1 J. Boas: Deutsche Aerzte-Zeitung, l895. Nos 2 and 3.