الفهرس 
Fady Makram BenjamineOnly 14 pages are availabe for public view
 |  | from | 32 |  |  |
| | | from | 32 | | |
Abstract
توطئة للحصول على درجة الماجستير فى
O
besity has increased prevalence to the extent that it has reached epidemic proportions and became a major public health concern.
Morbid obesity is considered a disease of excess energy stores in the form of fat. Clinically severe obesity correlates with a Body Mass Index (BMI) of greater than or equal to 40 kg/m² or a BMI of greater than or equal to 35 kg/m² accompanied by comorbid conditions.
The cause of obesity is complex and multifactorial and includes genetic factors, microbiological factor, environmental factors, behavioral factors, psychological factors, eating disorders, endocrine causes and drug induced obesity. There are several factors that are sharing in pathogenesis of obesity including hormonal and enzymatic cause.
Obesity increases the risk of many physical and mental conditions, obesity complications are either directly caused by obesity or indirectly related as diabetes mellitus, hypertension, dyslipidaemia, cardiovascular disease, atherosclerosis, Cerebrovascular disease, Pulmonary dysfunction, gastro-esophageal reflux, cholelithiasis, non-alcoholic fatty liver disease, deep venous thrombosis, pulmonary embolism, degenerative Joint disease, genital disorders, gestational diabetes, pre-eclampsia, and delivery complications.
Effective weight loss therapy can reverse many of the adverse effects of severe obesity. Available therapies include lifestyle changes (diet and exercise), very-low-calorie diets, pharmacologic therapy, and surgery. Of these, bariatric surgery is documented as the most consistently effective therapeutic intervention for the severely obese.
Surgery is usually successful in inducing substantial weight loss in the majority of obese patients with improvement or reversal of obesity-related comorbidities and is achieved primarily by an inevitable reduction in energy intake.
Bariatric procedures are based on two primary principles to promote weight loss: gastric restriction and intestinal mal-absorption. Roux-en-Y Gastric Bypass (RYGB) is considered the gold standard for bariatric surgery and the most common restrictive and mal-absorption procedure that surgically alters the stomach capacity using surgical staples. Weight loss is promoted by the restriction of the amount of food and the limitation of the absorption of food.
Complications of bariatric surgery could be classified into surgical and nutritional complications; furthermore, the surgical complications could be subdivided into early (<2 months) and late complications and includes: Anastomotic or staple line leaks, postoperative hemorrhage, venous thrombo-embolism, acute gastric distension, small bowel obstruction, gastro-jejunostomy anastomotic stricture, Marginal ulceration, Internal hernia, gastro-gastric fistula, gall stone disease and weight gain plus nutritional complications which includes: vitamin B12 deficiency, Iron deficiency, calcium and vitamin D deficiency, vitamin B9 (folates) deficiency, protein and carbohydrates deficiency.
Leak rates of 0–5.6% have been reported after gastric bypass surgery. Anastomotic leaks have been reported in 13% of patients undergoing re-visional bariatric surgery. The most common site of anastomotic leaks after gastric bypass is the gastro-jejunostomy, accounting for 50% of all anastomotic leaks.
Anastomotic leaks are associated with high morbidity and mortality. It is one of the leading causes of death following gastric bypass surgery.
The possible causes of leakage includes: Insufficient staple height in the linear or circular stapler, Insufficient suture lines, tearing at the top staple line, ischemia caused by division of jejunal mesentery or gastric pouch vessels, leaking cautery currents causing diathermy effects around the staples and patient non adherence to postoperative nutritional guidelines (i.e., overeating during the critical first weeks) could also play a role.
Clinical signs of leakage include: tachycardia, pyrexia, abdominal pain, purulent drain output, oliguria and nausea or vomiting. A recent study concluded that sustained tachycardia with a heart rate in excess of 120 beats per minute was a good indicator of an ASL.
Routine postoperative upper GI contrast studies are performed by many surgeons to detect leaks after gastric bypass surgery. Computer tomography (CT) scans are another common technique used to examine the anatomy of the roux limb and the anastomoses. If both the contrast studies and CT scans are equivocal, then endoscopy may be considered to assess the gastro-jejunostomy.
Leakage can be classified according to the day of appearance, its severity and its location. Conservative or surgical treatment can be employed properly if these 3 parameters are carefully evaluated.
Early operative management is the mainstay of treatment for ASLs following LRYGB. The operative goals are to confirm and repair the ASL, remove GI contents from the abdominal cavity and place closed suction drains.
There are different conservative methods to treat leakage from gastric bypass surgery in hemodynamicaly stable patient as Inhibition of gastrointestinal secretions by use of Somatostatin and total parentral nutrition, and intervention options include suturing (in cases of early detection), drainage of the abdomen (either per-cutaneously or operative), and endoscopic measures (fibrin glue, clips, stents). Antibiotics, fasting, and suction through a nasogastric tube are possible adjuncts.
In hemodynamically unstable patients with significant compromise of the anastomosis, emergent laparotomy and repair to the defect may be considered appropriate option after resuscitation.
In a hemodynamically stable patient with contained anastomotic leak, treatment with antibiotics and percutaneous drainage of fluid collections with initiation of total parenteral nutrition may be appropriate. The over-the-scope-clip (OTSC) system and StomaphyX is a newly designed method for treatment of leakage.
Conservative treatment includes supportive measures to stabilize the patient. These include provision of adequate drainage plus cutaneous protection; fluid/electrolyte balance; nutritional replacement and bowel rest via enteral or parenteral nutrition; and wound care and antibacterial therapy in patients with signs of systemic sepsis or local inflammation with pain.