Leak Pressure After Reinforcement in Gastric Specimens

The purpose of this study is to evaluate the mechanical strength of various staple line reinforcement techniques using the resected portion of stomach in patients undergoing laparoscopic sleeve gastrectomy. The specimen will be collected at the time of surgery, the previous staple line will be excised, and a new staple line with one of the investigatory reinforcement procedures will be applied. The staple line techniques to be used in this study include non-buttressed and non-imbricated oversewing, non-buttressed and imbricated suture line, buttressed stapling, and no reinforcement (see protocol for description of each). The specimen will then be taken to the morgue where the experimental procedure will be performed within 6 hours of specimen procurement. The specimen will be attached to a catheter with a pressure monitor and blue dye will be instilled into the specimen until leakage is seen. The presence of leakage indicates failure of the staple line. Detailed measurements of all specimens will be performed as will leak pressure and location in the specimen where leak occurred. The specimen will then be turned over to pathology to undergo routine pathologic examination. This experimental procedure has been used previously in published literature with animal samples, but never with human tissue. A possible reason for the lack of testing in the stomach staple line in patients after sleeve gastrectomy is that the technical aspects of bariatric surgery were developed using gastric bypass; a procedure where the stomach is divided but not excised. The investigators hypothesize that the specimens treated with staple line buttressing material will fail at a higher pressure than those without reinforcement. The investigators will also explore the location of the failure to determine if there is a consistent site of weakness. Should this study yield consistent results, it would help determine a standard approach for staple line reinforcement after laparoscopic sleeve gastrectomy. Additionally, should the location of the leak be consistent, this information may help drive technical changes that could decrease leak rate, an infrequent but potentially devastating risk of this and other weight loss surgeries.