Biomedical subjects
Publications and source records attributed to G Arlt.
A method is described for gastroscopic examination of the rat using a flexible bronchoscope. Endoscopy is performed under ether anesthesia and endotracheal intubation. Gastroscopies of 400 animals demonstrated, that this method is simple, highly sensitive and specific, and carries a low risk. It seems to be well suited for use in experimental gastroenterology.
In an experimental study on 269 rats the influence of the size of gastric resection and the type of anastomosis on the intragastric acidity was analyzed. It could be demonstrated, that the intragastric pH after gastrectomy is as well related to the amount of postresectional reflux as to the size of gastric resection. After gastrectomy of the same size the pH value ranged between 2 and 5.2 according to different reflux exposition because of different types of anastomosis. With identical reflux exposition different resection size resulted in an intragastric acidity between pH 3 and 5.2. We conclude from our results that the intragastric acidity after resection depends on the antagonism of acid and reflux.
The ulcer risk of the Roux-Y anastomosis following gastric resection was analyzed experimentally in 82 rats. After 1/3 gastric resection a Roux-Y gastrojejunostomy with jejunal loops of 3, 6, 9 and 15 cm was performed. 10 months postoperatively a follow-up was performed consisting of endoscopy, measurement of pH-values, analysis of gastric secretion and serum gastrin, gastric emptying tests and histamine stimulation. Endoscopically there was a high rate of stomal ulceration related to the length of the jejunal loop. In long Roux-Y loops (9 and 15 cm), that means under reflux-free conditions, ulcer incidence ranged from 72% to 92%. In short loops with reflux-exposed stomachs the frequency of ulceration was only 9%. With additional histamine stimulation there were stomal ulcers in 100% of the reflux-free animals, but only in 60% of the rats with short Roux-Y loops. In spite of resection acidity was high (pH 1.8) in reflux-free stomachs. Only the volume of gastric secretion and the amount of acid-output was reduced. Gastric acid secretion unbuffered by duodenal content is discussed as the major factor in the etiology of stomal ulcer in reflux-free stomachs. So the Roux-Y anastomosis following gastric resection is a modification of the Mann-Williamson experiment. Therefore reflux-free operations are heavily ulcer prone.
The ulcer risk of jejunal interposition following gastric resection was analyzed experimentally and clinically. There was a strong correlation between the rate of ulcer and the length of the interposed segment. The longer the segment and the better the reflux preventive effect was the higher was the ulcer risk. By additional vagotomy a partial protective effect could be obtained.
In an experimental study on 376 rats the ulcer risk was analyzed after Roux-Y-gastrojejunostomy resp. jejunal interposition. The following results were obtained: 5 to 10 months postoperatively stomal ulcers were found in up to 90%. The longer the jejunal segment, i.e. the lesser the reflux, the higher was the ulcer risk. The interval of ulcer manifestation could be shortened to 7 resp. 10 days by continuous histamine stimulation, while the differences between the groups remained unchanged. An extended resection was of negligible influence on the elevated ulcer risk in long jejunal segments, that means refluxfree conditions. The gastric pH was influenced by the length of the jejunal segment, the longer the segment, the more acid was the pH. With long, refluxfree segments normal pH-values could be observed despite of an extended gastric resection. An additional vagotomy caused a reduction but not an elimination of the ulcer risk. We conclude from our results, that there is a protective role of the postresectional intestino-gastric reflux on the gastrojejunal anastomosis. A refluxpreventive procedure is therefore heavily ulcerprone.
The ulcer risk of duodenogastric antireflux operations following gastric resection was analyzed experimentally in 162 rats. After gastric resection a Roux-Y gastrojejunostomy or jejunal transposition of various length were done. 10 month postoperatively a follow-up was performed consisting of endoscopy, analysis of gastrin and gastric secretion, gastric emptying tests and histamine stimulation. A high incidence of stomal ulceration was found, which was directly related to the length of the interposed jejunal segment. The reflux free stomachs within 10 month developed stomal ulcerations in 72.7%, after additional 2 mg/kg histamine stimulation in 100%. The aetiology of these ulcers seems to be acid related, because all reflux-free stomachs showed a very low pH. Reflux preventive operations are demonstrated to be a modification of the Mann-Williamson experiment. They should be used carefully or avoided.