Experimental in vivo canine model for gastric prolapse of laparoscopic adjustable gastric band system

The most prevalent long-term complications in patients undergoing laparoscopic adjustable gastric band (LAGB) surgery are symmetric pouch dilation and gastric prolapse (slippage). However, no published data or a reliable model are available to evaluate the actual mechanism of band slippage or how to prevent it. The objective of the present study was to construct an animal model of anterior gastric band prolapse and to use this model to evaluate the effectiveness of various arrangements of gastrogastric sutures and gastric wraps in preventing prolapse.

The esophagus of male mongrel dogs was accessed through the left chest, and a pressure transducer and an insufflation catheter were introduced. An AP-S Lap-Band (Allergan, Irvine, CA) filled to 10 cm(3) was placed using the pars flaccida technique. A standardized cut of meat was placed into the esophagus to simulate food impaction at a tight LAGB. After the placement of multiple different gastrogastric suture configurations, air was insufflated into the gastric pouch by way of the esophagus.

Prolapse, identical to that seen in clinical practice, was reliably reproduced in this model by increased esophageal pressure acting on a LAGB outlet obstruction. In addition, prolapse was reproduced with all gastrogastric configurations that did not secure the anterior gastric wall to within 1.5 cm of the lesser curve.

The results of the present study support the theory that prolapse is caused by esophageal peristalsis against an occlusion at the level of the LAGB. In this canine model, gastrogastric sutures encompassing the anterior gastric wall were integral to preventing prolapse.