The purpose of this study is to evaluate whether creating a gastrotomy (hole in the stomach) during gastric surgery increases a patient's risk of intra-abdominal infection.

We hypothesize that a gastrotomy does not contaminate the abdomen with clinically significant bacterial pathogens.

We propose to investigate the bacterial load and contamination patients experience during laparoscopic roux-en-y gastric bypass while having their gastrotomy for gastrojejunostomy. In all patients who undergo laparoscopic roux-en-y gastric bypass, the stomach must be opened to the peritoneal cavity while placing an anvil for gastrojejunostomy.

Samples of gastric fluid will be collected and sent for analysis in all patients. Samples of peritoneal fluid will be collected prior to and after the creation of the gastrotomy, using intraperitoneal irrigation with approximately 500 cc of normal saline. Bacterial counts and identification will be recorded for each sample.

Inclusion Criteria:

• any patient undergoing roux-en-y gastric bypass

Exclusion Criteria:

• lack of consent

observational studies patients morbidly obese.