gerd following laparoscopic sleeve gastrectomy

Conditions: Morbid Obesity

Summary: laparoscopic sleeve gastrectomy (lsg) creates a vertical gastrectomy which results in a narrow and tubular shape of stomach. the line of resection starts at 3-6 cm. from pylorus (antrum) toward to the angle of his. the gastric antrum plays a major role in gastric emptying, particularly for solids. hence, depending upon the starting point of gastric sleeve resection in each center, this can result in difference of the remaining gastric antrum which may affect gastric emptying time after this procedure.

laparoscopic sleeve gastrectomy (lsg), a purely restrictive procedure, has become recently one of the most popular bariatric surgical procedures in this decade because its surgical technique is simple but outcomes in regards to weight loss and co-morbidities improvement are excellent comparable to other procedures. nevertheless, this procedure carries one potential drawback namely "gastroesophageal reflux disease (gerd). the impact on gerd following lsg are inconsistent . additionally, the recent literature can be divided into two categories: those that support an increase in gerd prevalence after lsg and those that demonstrate a decrease in gerd prevalence after lsg. postoperatively, one of the proposed mechanisms for either increased or decreased gerd prevalence is gastric emptying time. delayed gastric emptying time can contribute to increase intra-gastric volume and pressure resulting in an increase in prevalence of gerd after surgery. on the other hand, accelerated gastric emptying time can cause decrease in gerd prevalence because of decrease in stomach volume and interorgan pressure after operation. in addition, lsg creates a vertical gastrectomy which results in a narrow and tubular shape of stomach. the line of resection starts at 3-6 cm. from pylorus (antrum) toward to the angle of his. the gastric antrum plays a major role in gastric emptying, particularly for solids. hence, depending upon the starting point of gastric sleeve resection in each center, this can result in difference of the remaining gastric antrum which may affect gastric emptying time after this procedure. the investigators hypothesize that a larger amount of gastric antrum will result in accelerated gastric emptying time which leads to less gerd prevalence. on the contrary, the less the remaining gastric antrum would result in delayed gastric emptying which contribute to more gerd prevalence. the investigators plan on identifying the prevalence of gerd in the patients who undergo lsg comparing those who have the sleeve beginning either 3 cm. or 6 cm. from pylorus. we will utilize 24 hour esophageal ph monitoring, esophageal manometry, upper gastrointestinal scintigraphy and esophagogastroduodenoscopy at preoperatively, 3 and 6 month postoperatively. ultimately, this study will help further clarify the most proper starting resected point of lsg (3 versus 6 cm. from pylorus) which results in the least gerd prevalence after surgery.

Eligibility criteria:
inclusion criteria: * any subject who has already been already cleared for and scheduled to undergo laparoscopic sleeve gastrectomy for the treatment of morbid obesity(utilizing nih1991 guideline for bariatric surgery) exclusion criteria: 1. patients not meeting entry criteria to undergo bariatric surgery procedures. 2. refusal to give informed consent. 3. age \ 70. 4. prior small intestinal or gastric resective surgery 5. existing coagulopathy (inr\>2.0, platelet count\<100,000) 6. severe reflux esophagitis.( los angeles classification for erosive esophagitis grade c,d) 7. hiatal hernia \> 2 cm(according to esophageal manometry or egd) 8. acquired or congenital immunodeficiencies 9. white blood cell count below normal range. 10. azotemia - serum creatinine \> 2.0 mg/dl