The purpose of this study is to determine the presence and characterization of stem cells in human peritoneal cavity. Peritoneal lavage fluid from patients who undergo elective open abdomen will be collected for this purpose. Peritoneal lavage is normally a routine part of abdominal surgical procedure and usually is discarded after surgery. The patient will undergo surgical procedure as usual and there will be no added procedures during surgery.

This study will collect and analyze peritoneal fluid for the existence and characteristics of stem cells from 15 patients undergoing scheduled elective intra-abdominal surgery by designated surgeons at Cedars-Sinai Medical Center. The types of abdominal surgery could be open abdominal surgery or laparoscopic surgery. Peritoneal washing is routinely done in abdominal surgeries. We will collect these fluids to analyze whether stem cells exist in human peritoneal cavity. The fluids will be collected in a sterile fashion. The collected fluid will be further processed in the laboratory for the purpose of the study.

Medical record review will be conducted. Information collected will include age, gender, past and current medical history, current indication for intra-abdominal surgery, substance exposure history, medication history which will be obtained from review of patients' medical records. The information will be maintained using coded entry and there will be no link between patient identifiers to the study codes.