Gastric Bypass: Surgical procedure in which the STOMACH is transected high on the body. The resulting small proximal gastric pouch is joined to any parts of the SMALL INTESTINE by an end-to-side SURGICAL ANASTOMOSIS, depending on the amounts of intestinal surface being bypasses. This procedure is used frequently in the treatment of MORBID OBESITY by limiting the size of functional STOMACH, food intake, and food absorption.Obesity, Morbid: The condition of weighing two, three, or more times the ideal weight, so called because it is associated with many serious and life-threatening disorders. In the BODY MASS INDEX, morbid obesity is defined as having a BMI greater than 40.0 kg/m2.Anastomosis, Roux-en-Y: A Y-shaped surgical anastomosis of any part of the digestive system which includes the small intestine as the eventual drainage site.Gastroplasty: Surgical procedures involving the STOMACH and sometimes the lower ESOPHAGUS to correct anatomical defects, or to treat MORBID OBESITY by reducing the size of the stomach. There are several subtypes of bariatric gastroplasty, such as vertical banded gastroplasty, silicone ring vertical gastroplasty, and horizontal banded gastroplasty.Weight Loss: Decrease in existing BODY WEIGHT.Bariatric Surgery: Surgical procedures aimed at affecting metabolism and producing major WEIGHT REDUCTION in patients with MORBID OBESITY.Laparoscopy: A procedure in which a laparoscope (LAPAROSCOPES) is inserted through a small incision near the navel to examine the abdominal and pelvic organs in the PERITONEAL CAVITY. If appropriate, biopsy or surgery can be performed during laparoscopy.Biliopancreatic Diversion: A surgical procedure which diverts pancreatobiliary secretions via the duodenum and the jejunum into the colon, the remaining small intestine being anastomosed to the stomach after antrectomy. The procedure produces less diarrhea than does jejunoileal bypass.Postoperative Complications: Pathologic processes that affect patients after a surgical procedure. They may or may not be related to the disease for which the surgery was done, and they may or may not be direct results of the surgery.Glucagon-Like Peptide 1: A peptide of 36 or 37 amino acids that is derived from PROGLUCAGON and mainly produced by the INTESTINAL L CELLS. GLP-1(1-37 or 1-36) is further N-terminally truncated resulting in GLP-1(7-37) or GLP-1-(7-36) which can be amidated. These GLP-1 peptides are known to enhance glucose-dependent INSULIN release, suppress GLUCAGON release and gastric emptying, lower BLOOD GLUCOSE, and reduce food intake.Obesity: A status with BODY WEIGHT that is grossly above the acceptable or desirable weight, usually due to accumulation of excess FATS in the body. The standards may vary with age, sex, genetic or cultural background. In the BODY MASS INDEX, a BMI greater than 30.0 kg/m2 is considered obese, and a BMI greater than 40.0 kg/m2 is considered morbidly obese (MORBID OBESITY).Jejunostomy: Surgical formation of an opening through the ABDOMINAL WALL into the JEJUNUM, usually for enteral hyperalimentation.Postoperative Period: The period following a surgical operation.Surgical Staplers: Fastening devices composed of steel-tantalum alloys used to close operative wounds, especially of the skin, which minimizes infection by not introducing a foreign body that would connect external and internal regions of the body. (From Segen, Current Med Talk, 1995)Peptide YY: A 36-amino acid peptide produced by the L cells of the distal small intestine and colon. Peptide YY inhibits gastric and pancreatic secretion.Steatorrhea: A condition that is characterized by chronic fatty DIARRHEA, a result of abnormal DIGESTION and/or INTESTINAL ABSORPTION of FATS.Gastric Fistula: Abnormal passage communicating with the STOMACH.Jejunum: The middle portion of the SMALL INTESTINE, between DUODENUM and ILEUM. It represents about 2/5 of the remaining portion of the small intestine below duodenum.Hyperoxaluria: Excretion of an excessive amount of OXALATES in the urine.Stomach: An organ of digestion situated in the left upper quadrant of the abdomen between the termination of the ESOPHAGUS and the beginning of the DUODENUM.Incretins: Peptides which stimulate INSULIN release from the PANCREATIC BETA CELLS following oral nutrient ingestion, or postprandially.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Body Mass Index: An indicator of body density as determined by the relationship of BODY WEIGHT to BODY HEIGHT. BMI=weight (kg)/height squared (m2). BMI correlates with body fat (ADIPOSE TISSUE). Their relationship varies with age and gender. For adults, BMI falls into these categories: below 18.5 (underweight); 18.5-24.9 (normal); 25.0-29.9 (overweight); 30.0 and above (obese). (National Center for Health Statistics, Centers for Disease Control and Prevention)Gastrostomy: Creation of an artificial external opening into the stomach for nutritional support or gastrointestinal compression.Follow-Up Studies: Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.Postoperative Care: The period of care beginning when the patient is removed from surgery and aimed at meeting the patient's psychological and physical needs directly after surgery. (From Dictionary of Health Services Management, 2d ed)Avitaminosis: A condition due to a deficiency of one or more essential vitamins. (Dorland, 27th ed)Gastric Inhibitory Polypeptide: A gastrointestinal peptide hormone of about 43-amino acids. It is found to be a potent stimulator of INSULIN secretion and a relatively poor inhibitor of GASTRIC ACID secretion.Food Preferences: The selection of one food over another.Coronary Artery Bypass, Off-Pump: Coronary artery bypass surgery on a beating HEART without a CARDIOPULMONARY BYPASS (diverting the flow of blood from the heart and lungs through an oxygenator).Diabetes Mellitus, Type 2: A subclass of DIABETES MELLITUS that is not INSULIN-responsive or dependent (NIDDM). It is characterized initially by INSULIN RESISTANCE and HYPERINSULINEMIA; and eventually by GLUCOSE INTOLERANCE; HYPERGLYCEMIA; and overt diabetes. Type II diabetes mellitus is no longer considered a disease exclusively found in adults. Patients seldom develop KETOSIS but often exhibit OBESITY.Prospective Studies: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.Appetite Regulation: Physiologic mechanisms which regulate or control the appetite and food intake.Hernia: Protrusion of tissue, structure, or part of an organ through the bone, muscular tissue, or the membrane by which it is normally contained. Hernia may involve tissues such as the ABDOMINAL WALL or the respiratory DIAPHRAGM. Hernias may be internal, external, congenital, or acquired.Reoperation: A repeat operation for the same condition in the same patient due to disease progression or recurrence, or as followup to failed previous surgery.Postprandial Period: The time frame after a meal or FOOD INTAKE.Surgical Stapling: A technique of closing incisions and wounds, or of joining and connecting tissues, in which staples are used as sutures.Omentum: A double-layered fold of peritoneum that attaches the STOMACH to other organs in the ABDOMINAL CAVITY.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Jejunal Diseases: Pathological development in the JEJUNUM region of the SMALL INTESTINE.Preoperative Period: The period before a surgical operation.Blood Glucose: Glucose in blood.Anastomosis, Surgical: Surgical union or shunt between ducts, tubes or vessels. It may be end-to-end, end-to-side, side-to-end, or side-to-side.Constriction, Pathologic: The condition of an anatomical structure's being constricted beyond normal dimensions.Ghrelin: A 28-amino acid, acylated, orexigenic peptide that is a ligand for GROWTH HORMONE SECRETAGOGUE RECEPTORS. Ghrelin is widely expressed but primarily in the stomach in the adults. Ghrelin acts centrally to stimulate growth hormone secretion and food intake, and peripherally to regulate energy homeostasis. Its large precursor protein, known as appetite-regulating hormone or motilin-related peptide, contains ghrelin and obestatin.Malabsorption Syndromes: General term for a group of MALNUTRITION syndromes caused by failure of normal INTESTINAL ABSORPTION of nutrients.Nesidioblastosis: An inherited autosomal recessive syndrome characterized by the disorganized formation of new islets in the PANCREAS and CONGENITAL HYPERINSULINISM. It is due to focal hyperplasia of pancreatic ISLET CELLS budding off from the ductal structures and forming new islets of Langerhans. Mutations in the islet cells involve the potassium channel gene KCNJ11 or the ATP-binding cassette transporter gene ABCC8, both on CHROMOSOME 11.Anastomotic Leak: Breakdown of the connection and subsequent leakage of effluent (fluids, secretions, air) from a SURGICAL ANASTOMOSIS of the digestive, respiratory, genitourinary, and cardiovascular systems. Most common leakages are from the breakdown of suture lines in gastrointestinal or bowel anastomosis.Candy: Sweet food products combining cane or beet sugars with other carbohydrates and chocolate, milk, eggs, and various flavorings. In the United States, candy refers to both sugar- and cocoa-based confections and is differentiated from sweetened baked goods; elsewhere the terms sugar confectionary, chocolate confectionary, and flour confectionary (meaning goods such as cakes and pastries) are used.Nephrolithiasis: Formation of stones in the KIDNEY.Satiety Response: Behavioral response associated with the achieving of gratification.Jejunoileal Bypass: A procedure consisting of the SURGICAL ANASTOMOSIS of the proximal part of the JEJUNUM to the distal portion of the ILEUM, so as to bypass the nutrient-absorptive segment of the SMALL INTESTINE. Due to the severe malnutrition and life-threatening metabolic complications, this method is no longer used to treat MORBID OBESITY.Gastrointestinal Hormones: HORMONES secreted by the gastrointestinal mucosa that affect the timing or the quality of secretion of digestive enzymes, and regulate the motor activity of the digestive system organs.Gastrectomy: Excision of the whole (total gastrectomy) or part (subtotal gastrectomy, partial gastrectomy, gastric resection) of the stomach. (Dorland, 28th ed)Hernia, Abdominal: A protrusion of abdominal structures through the retaining ABDOMINAL WALL. It involves two parts: an opening in the abdominal wall, and a hernia sac consisting of PERITONEUM and abdominal contents. Abdominal hernias include groin hernia (HERNIA, FEMORAL; HERNIA, INGUINAL) and VENTRAL HERNIA.Retrospective Studies: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.Caloric Restriction: Reduction in caloric intake without reduction in adequate nutrition. In experimental animals, caloric restriction has been shown to extend lifespan and enhance other physiological variables.Gastroenterostomy: A variety of surgical reconstructive procedures devised to restore gastrointestinal continuity, The two major classes of reconstruction are the Billroth I (gastroduodenostomy) and Billroth II (gastrojejunostomy) procedures.Vascular Patency: The degree to which BLOOD VESSELS are not blocked or obstructed.Calcium Citrate: A colorless crystalline or white powdery organic, tricarboxylic acid occurring in plants, especially citrus fruits, and used as a flavoring agent, as an antioxidant in foods, and as a sequestrating agent. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Saphenous Vein: The vein which drains the foot and leg.Pleasure: Sensation of enjoyment or gratification.Body Weight: The mass or quantity of heaviness of an individual. It is expressed by units of pounds or kilograms.Length of Stay: The period of confinement of a patient to a hospital or other health facility.UtahDumping Syndrome: Gastrointestinal symptoms resulting from an absent or nonfunctioning pylorus.