الفهرس 
Stomach AnatomyOnly 14 pages are availabe for public view
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Abstract
Obesity has become major health problem in both developed and developing nations, because of it’s high prevalence and causal relation- ship with serious medical and psychological complications (Sugerman, 2001).
Little is known about the aetiology of obesity. There are propably spectrum of different kinds of disorders as genetic, environmental or both which increase intake, decrease expendature of an obese individual (Pi-Sunyer, 1996).
Obesity may be defined as increase number and size of fat cells which lead to excess of body fat that frequently results in significant impairment of health (Myers, 1995).
Physical examination including measurement of weight and height is usually sufficient to diagnose obesity. The earlier method, involved tables of desirable weights at various heights. These tables based on illness and health rates. But currently, body mass index (BMI) is preffered formula that more closely correlates with body fat and metabolic complications of obesity. BMI is calculated as weight (W) in kg divided the square height (H) in meters = W/H2.According to BMI morbid obesity is approximately equavelent to > 40kg/m2 or 45kg above desirable weight (Gazet, 1996).
The risk of metabolic complications and comorbid factors is related to both BMI and waist circumference specifically the risks of hypertension (3.0 times higher) and risks of diabetes mellitus (2.9 Times higher) and risk of atherosclerosis (1.5 times higher) (Warner and Garret, 1999).
Reduction body weight can be achieved through medical treatment and/or surgical treatment. Medical treatment including therapeutic management and conservative management which including behavioral modification, dietary modification, exercise programs and appetite suppressant. All of these measures have not been effective in patient with marked obesity. Published scientific reports document that non operative methods are rarely successful especially in long term weight loss in severely obese adult only about 10% weight loss. It has been shown that majority of patients regain all weight loss over next 5 years (American society for Bariatric Surgery, 2001).
Surgical treatment is only proven method to achieve long term weight control for morbid obesity about 30% (Sugerman, 2001).
There are 2 types of surgical management of obesity:
1- Restrictive, to reduce food intake (e.g. vertical banded gastroplasty, gastric banding, and laparoscopic gastric banding (Lap. Band))
2- Combined restrictive and malabsorptive to reduce food absorption by gastric bypass in which stomach is connected to jejunum or ileum of small intestine bypassing the duodenum e.g. (jejunal bypass & billiary diversion) (Bethesda, 2005).
The surgical modalities used in bariatric surgery, initially used in treating other condition, and these modalities were found to cause weight loss postoperatively as a side effect
Trzebicky was the first to note nutritional in-balances in dogs following proximal and distal small bowel resection.
Von Eiselberg reported weight loss in humans after gastric or small intestinal resection in 1895. Kremen demonstrated a decade later that resection of 50% of the distal small intestine produced a profound interference with fat absorption and weight loss, where as resection of 50% to 70% of proximal small intestine resulted in normal nutritional balance. The first clinical trial of obesity surgery was performed by Payne and Dewind in 1955, but their end-to-side jejunal -transverse colon intestinal bypass procedure was restrected because of severe metabolic disturbances, liver failure, and protein-calorie malnutrition (Brunicardi et al., 2001).
In the late 1960s, a gastric bypass procedure was introduced by Mason and Ito that achieved weight loss through the production of a small gastric pouch that empties into a loop gastro-jejunostomy. Later, the transverse pouch was changed to a vertical lesser curvature pouch. Gastric pouch problems such as marginal ulcers and staple-line disruption led to the development of a transected gastric pouch (Schauer and Schirmer, 2005).
In 1981, Scopinaro and coworkers reported initial results with bilio-pancreatic bypass, which combines a subtotal gastrectormy with a Roux-en-Y gastro-ileal anastomosis and a jejuno-ileal anastomosis 50 cm proximal to the ileo-cecal valve to allow absorption of nutrients in the distal 50-cm common channel. Results reported by Scopinaro and coworkers have been excellent, with reduction in excess weight of nearly 75%. Marcean and associates modified the technique of Scopinaro and developed the bilio-pancreatic diversion with a duodenal switch (Brunicardi et al., 2001).
In the late 1970s, gastric banding was also introduced which used various banding materials to create a small upper gastric pouch. This is the least invasive bariatric procedure though complications like band migration and slippage (Schauer ad Schirmer, 2005).
In an attempt to restrict food intake, horizontal gastroplasty was developed. Its failure was due to proximal fundal pouch dilatation, outlet dilatation and staple - line breakdown.
In 1980, Mason began performing the vertical banded gastroplasty (VBG). It consists of a stapled vertical gastric channel along the lesser curvature, extending to the angle of His. Sufficient weight loss has been generally achieved (Schauer and Schirmer, 2005).
Following the introduction and rapid acceptance of laparoscopic cholecystectomy, surgeons began performing laparoscopic bariatric procedures. Chelala and Belachew and their colleagues reported performing laparoscopic adjustable gastric banding in 1992.
Laparoscopic Roux-en-Y gastric bypass and laparoscopic vertical banded gastroplasty were reported in 1993 by Wittgrove (Brunicardi et al., 2001)
In the late 1960s, a gastric bypass procedure was introduced by Mason and Ito.In this procedure, the jejunal loop was brought up to the proximal stomach often under tension which increased the likelihood of an anastomotic leak, which would be catastrophic because of agrees of copious caustic gastro-duodeno-bilio-pancreatic secretions.Thus, the configuration was changed to a Roux-en-Y (which decreased the stretch on the mesentery and eliminated bile reflux (Deitel, 2002).
With the availability of surgical staples, the ability to create a partition across the upper stomach using staples was increased without the need to remove any part of the stomach (Sugerman, 1997).
Some workers partitioned the stomach by application of a linear stapler. But staple-line disruption and development of an ulcer on the jejunal side of the anastomosis (marginal ulcer) (Sugerman and De Maria, 2003).
Thus, many surgeons divide the stomach, leaving an upper tiny pouch and the large lower gastric segment. Patients generally maintain a long-term loss of 50% of excess body weight. In order to increase the rapidity of weight loss, the bilio-pancratic or Roux limbs were moved more distally (Deitel, 2002).
But with the far distal Roux-en-Y configuration, excess protein malabsorption and hypo-albuminemia may be a complication (Rhode and Mac Lean, 2000).
**Complications of gastric bypass:It may be due to: * Intraoperative
1- Airway Management and General Anesthesia.
2- Upper Abdominal Surgery:It can be divided into three categories:
a- Hemorrhage in the surgical field (including splenic injury).
b- Injury to GI tract and adjacent organs; namely the: diaphragm, oesophagus, liver, spleen or pancreas.
c- Stapling misadventures (Podnos,et al.,2003).
**Postoperative Complications:
A) Early: (within one month)
DVT and pulmonary embolism.
Atelectasis, pneumonia and pleural effusion.
Gastrointestinal leaks.
Seroma and wound infection.
Dehiscence of abdominal wall.
Acute pancreatitis.
Acute gastric dilatation and vomiting.
B) Late: (after one month)
Incisional hernia.
Cholelithiasis.
Stomal ulceration.
Stomal stenosis (Persistant vomiting).
Staple line dehiscence.
Failure to lose weight.
Reflux oesophagitis.
Mechanical bowel obstruction.
Band erosion into the stomach.
Intolerance of the procedure.
Malnutrition and vitamin deficiencies (Marema, et al., 2005).