[Intestinal motility after jejunum interposition and Roux-Y reconstruction--an animal experiment study].

An experimental study in animals was conducted to evaluate the motility patterns after total gastrectomy. Eight male beagle dogs (22.5-27.2 kg) had total gastrectomy with standardized designs of gastric substitution: (1) jejunal interposition (JI, n = 4); (2) Roux-en-Y reconstruction (RY, n = 4). Motility patterns were detected with perfused manometry (eight measuring ports), sequential scintigraphic emptying studies of the gastric substitute (caloric and acaloric medium viscosity test meals), and a hydrogen breath test with lactulose. The preoperative studies of the same individuals served as controls (CO). To detect postgastrectomy adaptation processes the postoperative studies were conducted 6-8, 12-14, and 24-30 weeks after total gastrectomy. The emptying of the gastric substitutes was markedly accelerated compared with CO after 6 months (T50: 5.8-8.1 min). In contrast to the preoperative studies, caloric test meals caused a trend to increase the velocity of the evacuation. The intestinal transit time was accelerated too in the weeks immediately, after the operation. In JI dogs intestinal transit was then markedly slowed and led to a highly significant difference after 6 months compared to RY animals (CO: 101 +/- 26min, JI: 104 +/- 18.2min, RY: 71.3 +/- 13.4min; p < 0.01). Pathologic motility patterns could be identified as the cause of this observations: RY dogs showed a marked increase of the intestinal motility index in the proximal jejunum (p < 0.0001) and a dissociation between the motility patterns of the duodenum and the gastric substitute. The observations gave rise for the supposition that this parts of the small bowel might generate two independent pacemarkers that both influence the lower intestinal parts after RY reconstruction. We conclude that the motility patterns of the entire small bowel highly influence the postoperative function of reconstruction procedures after total gastrectomy. The emptying velocity of the jejunal gastric substitute does not seem to have a major influence on the postoperative results. According to motility patterns jejunal interposition has a better outcome than Roux-en-Y reconstruction.