Myoelectric effects and histology after stapled occlusion of the small bowel

Braun enteroenterostomy with stapled occlusion of the afferent limb has been advocated to treat bile gastritis and to avoid the motility effects of Roux-en-Y gastrojejunostomy. However, the motility effects of stapled occlusion are unknown. Myoelectric activity and histologic features were studied after stapled occlusion of the small bowel in a canine model. A 35 cm "recirculating loop" was created with a side-to-side anastomosis, beginning 25 cm from the ligament of Treitz. Serosal electrodes were placed at 5 cm intervals on the loop; at a second operation in one dog and simultaneously in three dogs, the bowel was occluded midway between two electrodes with 4.8 mm staples. Fasting recordings were obtained at weekly intervals to 6 months after surgery and were analyzed for slow wave frequency proximal and distal to the staple line and for propagation time of phase 3 of the migrating myoelectric complex across the staple line. The side-to-side anastomosis did not alter myoelectric activity. However, after stapled occlusion of the small bowel, the slow wave frequency dropped from a mean of 18.2 +/- 0.4 cpm proximally to 15.4 +/- 1.0 cpm distally (p less than 0.05). This correlated with loss of myogenic continuity in three of four animals. Propagation of phase 3 slowed across the staple line (115 +/- 27 seconds versus 47 +/- 9 seconds) (p less than 0.02). The bowel lumen recannulated in all animals. Stapling across the small bowel alters myoelectric activity, and occlusion of the bowel lumen may not be permanent.