Predictors of gallstone formation after bariatric surgery: a multivariate analysis of risk factors comparing gastric bypass, gastric banding, and sleeve gastrectomy.

BACKGROUND: Risk factors for gallstone formation in the general population have been well studied while those after weight reduction surgery are unknown. The aim of this study was to identify the risk factors for the development of symptomatic gallstones after bariatric surgery. METHOD: Retrospective review was performed for patients who underwent laparoscopic Roux-en-Y gastric bypass (RYGBP), adjustable gastric banding (LAGB) or sleeve gastrectomy (LSG) between 2004 and 2006. Statistical evaluation was performed using a univariate and multivariate analysis. Risk factors, including age, gender, preoperative body mass index (BMI), BMI > 45 kg/m(2), diabetes mellitus, hyperlipidemia, types of operation, and weight loss >25% of original weight, were analyzed for their association with postoperative symptomatic gallstones formation. RESULTS: 670 laparoscopic RYGBP, 47 LAGB, and 79 LSG were performed in our institute. Preoperative gallbladder disease, as indicated by presence of gallstones or sludge on preoperative transabdominal ultrasound, or previous cholecystectomy, were found in 25.3, 14.9, and 30.4% of patients who subsequently had RYGBP, LAGB, and LSG, respectively. A total of 586 patients were included for analysis. Mean follow-up was 25.9 (range 12-42) months. Overall rate of symptomatic gallstone formation was 7.8% and mean time for its development was 10.2 (range 2-37) months. Incidence of symptomatic gallstones with complications as initial presentation was found in 1.9% of the patients. Logistic regression analysis showed that only postoperative weight loss of more than 25% of original weight was associated with symptomatic gallstones formation [B = 1.482, SE = 0.533, odds ratio 4.44, 95% confidence interval (CI) 1.549-12.498, p = 0.005]. CONCLUSIONS: Traditional risk factors for gallstone formation in the general population are not predictive of symptomatic gallstone formation after bariatric surgery. Weight loss of more than 25% of original weight was the only postoperative factor that can help selecting patients for postoperative ultrasound surveillance and subsequent cholecystectomy once gallstones were identified.

Symptomatic gallstones after sleeve gastrectomy.

BACKGROUND: Cholelithiasis is a common complication after bariatric surgery. Pure restrictive procedures such as sleeve gastrectomy and gastric banding theoretically should result in less gallstone formation because the food continues to follow the normal gastrointestinal transit, maintaining the enteric-endocrine reflex intact. To the authors' knowledge, the literature has no studies that analyze the incidence of gallstone formation after sleeve gastrectomy. This study aimed to compare the rates of symptomatic gallstones between laparoscopic Roux-en-Y gastric bypass (RYGBP) and sleeve gastrectomy (SG). METHODS: A retrospective chart review of patients who underwent laparoscopic RYGBP and SG between 2004 and 2006 was performed. The patients with previous cholecystectomy, known gallstones with or without concomitant cholecystectomy, and previous weight-reduction operations were excluded from the analysis. The outcome measures were the numbers of patients who had experienced symptomatic and complicated gallstones. Using Cox regression analysis, comparisons was made between the patients with laparoscopic RYGBP (group A) and those with laparoscopic SG (group B). RESULTS: Groups A excluded 174 (26%) of 670 patients, and group B excluded 27 (34.2%) of 79 patients. The patients in group A had a significantly higher preoperative body mass index (BMI) than those in group B. Additionally, more group A than group B patients had a BMI exceeding 45 and more than a 25% loss of original weight. No significant difference in the development of symptomatic (8.7% vs. 3.8%; p = 0.296) or complicated (1.8% vs. 1.9%; p = 0.956) gallstones was noted between the two groups CONCLUSIONS: There was no significant difference in symptomatic or complicated gallstone disease between the patients treated with laparoscopic SG and those treated with laparoscopic RYGBP. Routine prophylactic cholecystectomy should not be recommended for weight reduction during laparoscopic SG.

Hemorrhagic and thromboembolic complications after bariatric surgery in patients receiving chronic anticoagulation therapy.

BACKGROUND: Perioperative management of bariatric surgical patients receiving chronic anticoagulation requires an understanding of potential hemorrhagic and thromboembolic risks. The aim of this study is to evaluate hemorrhagic and thromboembolic complications in morbidly obese patients who are on oral anticoagulation treatment and subsequently undergo laparoscopic bariatric surgery. METHODS: The medical records of all laparoscopic Roux-en-Y gastric bypass (LRYGB) patients from June 2001 to March 2006 were retrospectively reviewed. In addition, data of patients who received chronic anticoagulation therapy with Coumadin and underwent laparoscopic Roux-en-Y gastric bypass was analyzed. Clinical parameters included length of hospitalization, hemorrhagic complications, thromboembolic complications, conversion rate, reoperation, and blood transfusion. RESULTS: During the study period, 1,700 consecutive patients underwent bariatric surgery for the treatment of morbid obesity. Of these, 21 patients were treated with chronic oral anticoagulation; 3 of the 21 (14%) had hemorrhagic complications: one patient had intraluminal hemorrhage and two patients had intraabdominal hemorrhage. Two patients required blood transfusion, and one patient underwent surgical reintervention. None of the 21 laparoscopic operations were converted to open procedures. There were no postoperative mortalities, and there were no thromboembolic events in this series. CONCLUSIONS: Laparoscopic bariatric surgery can be performed relatively safely in morbidly obese patients who are treated with chronic oral anticoagulation. Even in the presence of bleeding, patients can be successfully treated without the need for reoperation.

Incidence of deep vein thrombosis in morbidly obese patients undergoing laparoscopic Roux-en-Y gastric bypass.

BACKGROUND: To define the incidence of deep vein thrombosis in morbidly obese patients undergoing laparoscopic Roux-en-Y gastric bypass. METHODS: A retrospective study was conducted for all patients undergoing laparoscopic Roux-en-Y gastric bypass from 2004 to 2006. The data collected included patient demographics, body mass index, operative time, conversion rate, thromboprophylaxis measures, hospital stay, and complications. RESULTS: Of the 618 patients included in the study, 451 (73%) were women and 167 (27%) were men, with a mean age of 44 years (range 18-78). The preoperative body mass index was 49 kg/m(2) (range 35-90). All patients received the same thromboprophylaxis regimen. All surgical procedures were performed and completed laparoscopically, with a mean operative time of 93 minutes (range 50-196). All patients underwent lower extremity color Doppler ultrasonography within the first 24 hours after the surgical procedure. The mean hospital stay was 4 days (range 2-21). The most common in-hospital complication was basal atelectasis in 52 patients (8.4%), followed by gastrointestinal bleeding in 10 (1.6%), and anastomotic leak in 6 (1%). The postoperative follow-up visits were done at 2, 8, 12, 24, and 52 weeks after surgery; no mortality occurred. The overall rate of deep vein thrombosis in the group of 500 consecutive patients was .2%, with no clinically significant pulmonary embolism; 9 patients presented with postoperative bleeding. CONCLUSION: The overall rate of deep vein thrombosis in this group of patients was low, most probably because of the use of thromboprophylaxis.

Multisite Image Data Collection and Management Using the RSNA Image Sharing Network.

The execution of a multisite trial frequently includes image collection. The Clinical Trials Processor (CTP) makes removal of protected health information highly reliable. It also provides reliable transfer of images to a central review site. Trials using central review of imaging should consider using CTP for handling image data when a multisite trial is being designed.