الفهرس 
Complications of obesityOnly 14 pages are availabe for public view
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Abstract
Obesity is simply defined as ”excessive amount of body fat” and should be considered a chronic disease, as it has definite mortality and morbidity.
The lack of direct methods has led to development of various models and indirect methods for estimation of fat and fat-free mass, all of which are imperfect and require a number of assumptions.
The most widely accepted measure of obesity is the body mass index (BMI) which equals patient weight in kilograms divided by the square of his or her height in meters. Morbid obesity is having a BMI greater than 40 kg/m2 or a BMI greater than 35 kg/m2 with concomitant obesity-related morbidity.
Appetite is influenced by many factors that are integrated by the brain, most importantly within hypothalamus. Signals that impinge on the hypothalamic centre include neural afferents, hormones and metabolites.
The incidence of obesity is steadily rising. Morbid obesity is associated with a large number of problems. Several of these problems are underlying causes for the earlier mortality associated with obesity and include; coronary artery disease, hypertension, impaired cardiac function, adult onset diabetes mellitus, venous stasis and hypercoagulability leading to an increased risk of pulmonary embolism, increased risk of uterine, breast and colon cancer and necrotizing panniculitis.
The primary goal of treatment is to improve obesity related co-morbid conditions and reduce the risk of developing future co-morbidities.
Treatment of morbid obesity should begin with simple lifestyle changes, including moderation of diet and initiation of regular exercise such as walking. The treatment of associated co-morbidities should be addressed expeditiously.
Adjuvant pharmacologic treatments should be considered for patients with a BMI >30 kg/m2 or with a BMI >27 kg/m2 who also have concomitant obesity-related diseases and for whom dietary and physical activity therapy has not been successful.
Two drugs are FDA-approved for long-term obesity treatment. Those are sibutramine (Meridia) and Xenical (Orbistat).
However, because the only effective treatment for morbid obesity is bariatric surgery, these are the initial steps to be taken in preparation for the more definitive treatment. Bariatric surgery offers the only means of delivering sustained weight loss.
Bariatric surgical techniques are divided into two groups: malabsorptive and restrictive procedures. In general, restrictive procedures are simpler to perform and are accompanied by less procedural complications than malabsorptive procedures.
The original purely malabsorptive procedures such as jejuno-ileal bypass are no longer performed due to their unacceptably high late complication rate. They have been replaced by restrictive or combined operations. Open surgery has largely been replaced by a laparoscopic approach. The most common operations performed are: vertical banded gastroplasty, adjustable gastric banding, biliopancreatic diversion and Roux-en-Y gastric bypass.
The sleeve gastrectomy is a new tool in the surgical treatment of the morbidly obese and the superobese patients. It was conceived as the restrictive part of a more complex procedure that combines malabsorptive and restrictive concepts: the biliopancreatic diversion with duodenal switch.
In recent years, laparoscopic sleeve gastrectomy (LSG) as a single-stage procedure for the treatment of morbid obesity is becoming increasingly popular. Of continuing concern are the rate of postoperative complications and the lack of consensus as to surgical technique.
Patients elected for SG should have complete clinical and multidisciplinary evaluation and preparation.
SG consists of creating a maximal gastric reservoir or tube of 150 to 200 ml but, as an isolated procedure, the gastric pouch size usually varies from 60 to 120 ml.
SG achieves weight loss by gastric restriction and decreasing the circulating level of ghrelin hormone which play a key role in the energy balance.
SG does not involve alterations in the small bowel anatomy and is therefore rarely associated with metabolic complications. It is also simpler to perform with less procedural risks when compared with malabsorptive operations and achieve good weight loss. This reduction in mortality and major complications has lead to their current popularity.