Glucose Metabolism After Gastric Banding and Gastric Bypass in Individuals With Type 2 Diabetes: Weight Loss Effect

OBJECTIVE

The superior effect of Roux-en-Y gastric bypass (RYGB) on glucose control compared with laparoscopic adjustable gastric banding (LAGB) is confounded by the greater weight loss after RYGB. We therefore examined the effect of these two surgeries on metabolic parameters matched on small and large amounts of weight loss.

RESEARCH DESIGN AND METHODS

Severely obese individuals with type 2 diabetes were tested for glucose metabolism, β-cell function, and insulin sensitivity after oral and intravenous glucose stimuli, before and 1 year after RYGB and LAGB, and at 10% and 20% weight loss after each surgery.

RESULTS

RYGB resulted in greater glucagon-like peptide 1 release and incretin effect, compared with LAGB, at any level of weight loss. RYGB decreased glucose levels (120 min and area under the curve for glucose) more than LAGB at 10% weight loss. However, the improvement in glucose metabolism, the rate of diabetes remission and use of diabetes medications, insulin sensitivity, and β-cell function were similar after the two types of surgery after 20% equivalent weight loss.

CONCLUSIONS

Although RYGB retained its unique effect on incretins, the superiority of the effect of RYGB over that of LAGB on glucose metabolism, which is apparent after 10% weight loss, was attenuated after larger weight loss.

Treatment with Lavender Aromatherapy in the Post-Anesthesia Care Unit reduces Opioid Requirements of Morbidly Obese Patients Undergoing Laparoscopic Adjustable Gastric Banding

BACKGROUND

Parenteral administration of opioids and NSAIDs has been the mainstay for postoperative pain control in patients undergoing laparoscopic adjustable gastric banding (LAGB). Both classes of drugs, however, are associated with serious adverse effects. An addition of complimentary analgesic techniques may decrease requirement for traditional analgesics, thus reducing the incidence of side-effects. We designed the study to evaluate the effectiveness of Lavender aromatherapy in reducing opioid requirements after LAGB.

METHODS

A prospective randomized placebo controlled study was carried out on 54 patients undergoing LAGB. Upon arrival to the post-anesthesia care unit (PACU), patients in the study group were treated with lavender oil, which was applied to the oxygen face mask; the control group patients received nonscented baby oil. Postoperative pain was treated with morphine. Numerical rating scores (0-10) were used to measure the level of pain at 5, 30, and 60 min. Sedation was evaluated using the Observer Assessment of Alertness/Sedation scale (0-5). Data analyzed included the amount of opioids, NRS, OAA/S, PACU discharge time, as well as the incidence of side-effects.

RESULTS

The two groups were comparable with regard to patient characteristics, intraoperative drug use, and surgical time. Significantly more patients in the Placebo group (PL) required analgesics for postoperative pain (22/27, 82%) than patients in the Lavender group (LAV) (12/26, 46%) (P = .007). Moreover, the LAV patients required significantly less morphine postoperatively than PL patients: 2.38 mg vs 4.26 mg, respectively (P = .04). There were no differences in the requirements for post-operative antiemetics, antihypertensives, or PACU discharge time.

CONCLUSIONS

Our results suggest that lavender aromatherapy can be used to reduce the demand for opioids in the immediate postoperative period. Further studies are required to assess the effect of this therapy on clinically meaningful outcomes, such as the incidence of respiratory complications, delayed gastric emptying, length of hospital stay, or whether this therapy is applicable to other operations.

Fatal complications of bariatric surgery

BACKGROUND

Bariatric surgery is an increasingly used method to treat morbid obesity. The mortality rate among patients undergoing bariatric operations is generally quoted as between 0.05-2.0%. Our focus was not on mortality rates but rather on the reasons patients die following the procedures. In New York City, deaths that are due to predictable complications of appropriate therapy are certified as therapeutic complications.

METHODS

We retrospectively reviewed all deaths investigated by the Office of the Chief Medical Examiner in New York City between 1997 and 2005 in which bariatric surgery had been performed. We report the fatal complications, the interval between surgery and death, the type of procedure, and coexisting morbidities.

RESULTS

Autopsies were performed on 95% of these fatalities. There were 97 deaths due to therapeutic complications of the operations. The interval between the initial surgery and death ranged from several hours to years. The most common complication was an anastomotic leak with subsequent infection. A high percentage of deaths occurred after discharge (40%) and/or >30 days after surgery (37%). There were 8 deaths from complications of bariatric surgery that occurred >1 year after surgery.

CONCLUSIONS

Studies that report the mortality rate during hospitalization or within 30 days of surgery, underestimate the actual incidence. Bariatric surgery carries both short- and long-term risks.

Short-term results in 53 US obese pediatric patients treated with laparoscopic adjustable gastric banding

BACKGROUND

Obesity in the adolescent population has reached epidemic proportions. Although diet and behavior modification can help a minority of teenagers, most of these patients go on to become obese adults. Recently, surgical intervention for morbid obesity has gained increasing support. To date, this has only included gastric bypass procedures. However, this procedure carries at least a 1% mortality rate even in the hands of the most experienced surgeons. Therefore, our center has been using laparoscopic adjustable gastric banding (LAGB) to treat adolescents with morbid obesity. This analysis is a report of our short-term results in our first 53 patients.

METHODS

All adolescents aged 13 to 17 years who had undergone LAGB at our institution and had been entered into our prospectively collected database since 2001 were reviewed. Data collected preoperatively included age, sex, race, and body mass index (BMI). Postoperatively recorded data included length of stay, operative morbidity, need for reoperation, as well as percentage of excess weight loss (%EWL) and BMI at 3-month intervals.

RESULTS

Fifty-three teenagers aged 13 to 17 years (mean, 15.9 years) underwent LAGB at our institution since September 2001. Of these, 41 were female and 12 were male. The mean preoperative weight was 297 +/- 53 lb and the mean initial BMI was 47.6 +/- 6.7 kg/m2. The %EWL was 37.5 +/- 17.0 at 6 months, 62.7 +/- 27.6 at 1 year, and 48.5 +/- 15.6 at 18 months of follow-up. There were no intraoperative complications. Two patients had band slips that required laparoscopic repositioning, and 2 patients developed a symptomatic hiatal hernia that required laparoscopic repair. All of these procedures were performed as outpatient procedures. A fifth patient developed a wound infection requiring incision and drainage. Other complications included mild hair loss in 5 patients, iron deficiency in 4 patients, nephrolithiasis and cholelithiasis in 1 patient, and gastroesophageal reflux in 1 patient.

CONCLUSIONS

Laparoscopic adjustable gastric banding is not only a safe operation for morbidly obese pediatric patients, but also represents an effective treatment strategy with a %EWL of approximately 50% at both 1 year and 18 months of follow-up. Because of the minimal morbidity and complete absence of mortality of the LAGB, it is the optimal surgical option for pediatric patients with morbid obesity.

Objective Comparison of Complications Resulting from Laparoscopic Bariatric Procedures

BACKGROUND

Several surgical treatment options for morbid obesity exist. Currently, there are no studies that objectively compare complication rates after laparoscopic bariatric operations performed at a single institution. We objectively classify and compare complications resulting from laparoscopic adjustable gastric banding (LABG), Roux-en-Y gastric bypass (RYGB), and biliopancreatic diversion (BPD) with duodenal switch (DS).

STUDY DESIGN

A retrospective review of a prospective database of all patients undergoing laparoscopic bariatric operation was performed. Complications were categorized according to severity score using a well-described classification system and compared between procedures.

RESULTS

From September 2000 to July 2003, 780 laparoscopic bariatric operations were performed: 480 LAGB, 235 RYGB, and 65 BPD+/-DS. There was one late death. Total complication rates were: 9% for LAGB, 23% for RYGB, and 25% for BPD+/-DS. Complications resulting in organ resection, irreversible deficits, and death (grades III and IV) occurred at rates of 0.2% for LAGB, 2% for RYGB, and 5% for BPD+/-DS. LAGB group had a statistically significant lower overall complication rate, both by incidence and severity, as compared with other groups (p < 0.001). After controlling for differences of admission body mass index, gender, and race, the LAGB group had an almost three and a half times lower likelihood of a complication compared with the RYGB group (odds ratio, 3.4; 95% CI, 2.2-5.3, p < 0.001) and had an over three and a half times lower likelihood of a complication compared with the BPD with DS group (odds ratio, 3.6; 95% CI, 1.8-7.1, p < 0.001). There was no statistically significant difference between complication rates of RYGB and BPD+/-DS.

CONCLUSIONS

Bariatric operation complication rates range from 9% to 25%; very few complications are serious. Laparoscopic adjustable gastric banding is the safest operation in terms of complication rate and severity when compared with laparoscopic Roux-en-Y gastric bypass or laparoscopic malabsorptive operations.

U.S. experience with 749 laparoscopic adjustable gastric bands: intermediate outcomes

BACKGROUND

Laparoscopic adjustable gastric band (LAGB) has consistently been shown to be a safe and effective treatment for morbid obesity, especially in Europe and Australia. Data from the U.S. regarding the LAGB has been insufficient. This study reveals our experience with 749 primary LAGB over a 3-year period in a U.S. university teaching hospital.

METHODS

All data was prospectively collected and entered into an electronic registry. Characteristics evaluated for this study include preoperative age, BMI, gender, race, conversion rate, operative time, hospital stay, percent excess weight loss (%EWL) and postoperative complications. Annual esophagrams were performed

RESULTS

From July 2001 through September 2004, 749 patients (531 females, 218 males) underwent LAGB for the treatment of morbid obesity. There were 630 Caucasians, 61 African-Americans, and 49 Latin Americans, with a mean age of 42.3 (range 18, 72 years) and mean BMI of 46.0 +/- 7.0 (range 35, 91.5 kg/m(2)). There was one conversion to open (0.1%). Median operative time and hospital stay were 60 minutes and 23 hours, respectively. The mean %EWL at 1 year, 2 years, and 3 years was 44.4 (+/-17.8), 51.8 (+/-20.9), and 52.0 (+/-19.6), respectively. There were no mortalities. Postoperative complications occurred in 12.8% of patients: 1.5% acute postoperative band obstruction, 0.9% wound infection, 2.9% gastric prolapse ("slip"), 2.0% concentric pouch dilatation (without slip), 0.8% aspiration pneumonia, 2.4% port/tubing problems, 0.3% severe esophageal dilatation/dysmotility (reversible), and 1.5% overall band removal.

CONCLUSION

These American results substantiate the data from abroad that LAGB is a safe and effective treatment for morbid obesity.

Laparoscopic Bariatric Surgery in Super-obese Patients (BMI>50) is Safe and Effective: A Review of 332 Patients

BACKGROUND

Bariatric surgery in super-obese patients (BMI >50 kg/m(2)) can be challenging because of difficulties in exposure of visceral fat, retracting the fatty liver, and strong torque applied to instruments, as well as existing co-morbidities.

METHODS

A retrospective review of super-obese patients who underwent laparoscopic adjustable gastric banding (LAGB n=192), Roux-en-Y gastric bypass (RYGBP n=97), and biliopancreatic diversion with/without duodenal switch (BPD n= 43), was performed. 30 day peri-operative morbidity and mortality were evaluated to determine relative safety of the 3 operations.

RESULTS

From October 2000 through June 2004, 331 super-obese patients underwent laparoscopic bariatric surgery, with mean BMI 55.3 kg/m(2). Patients were aged 42 years (13-72), and 75% were female. When categorized by operation (LAGB, RYGBP, BPD), the mean age, BMI and gender were comparable. 6 patients were converted to open (1.8%). LAGB had a 0.5%, RYGBP 2.1% and BPD 7.0% conversion rate (P=0.02, all groups). Median operative time was 60 min for LAGB, 130 min for RYGBP and 255 min for BPD (P<0.001, all groups). Median length of stay was 24 hours for LAGB, 72 hours for RYGBP, and 96 hours for BPD (P <0.001). Mean %EWL for the LAGB was 35.3+/-12.6, 45.8+/-19.4, and 49.5+/-18.6 with follow-up of 87%, 76% and 72% at 1, 2 and 3 years, respectively. Mean %EWL for the RYGBP was 57.7+/-15.4, 54.7+/-21.2, and 56.8+/-21.1 with follow-up of 76%, 33% and 54% at 1, 2 and 3 years, respectively. Mean %EWL for the BPD was 60.6+/-15.9, 69.4+/-13.0 and 77.4+/-11.9 with follow-up of 79%, 43% and 47% at 1, 2 and 3 years, respectively. The difference in %EWL was significant at all time intervals between the LAGB and BPD (P<0.004). However, there was no significant difference in %EWL between LAGB and RYGBP at 2 and 3 years. Overall perioperative morbidity occurred in 27 patients (8.1%). LAGB had 4.7% morbidity rate, RYGBP 11.3%, and BPD 16.3% (P=0.02, all groups). There were no deaths.

CONCLUSION

Laparoscopic bariatric surgery is safe in super-obese patients. LAGB, the least invasive procedure, resulted in the lowest operative times, the lowest conversion rate, the shortest hospital stay and the lowest morbidity in this high-risk cohort of patients. Rates of all parameters studied increased with increasing procedural complexity. However, the difference in %EWL between RYGBP and LAGB at 2 and 3 years was not statistically significant.

Factors influencing patient choice for bariatric operation

BACKGROUND

No study has surveyed the factors that influence morbidly obese patients' preference for a particular bariatric operation.

METHOD

469 consecutive patients in 2 major bariatric surgery centers in the United States (US, 124) and Australia (AU, 345) were prospectively studied to determine referral pattern and reason for their choice of operation.

RESULTS

The predominant operation was laparoscopic adjustable gastric banding (LAGB) in both US (75%) and AU (83%) centers. Gender (70% female), BMI (45 kg/m2) and age (42.5 years) were similar in both cohorts. In Australia, 53% had referral initiated by primary doctors and 25% by another patient, while in the US, 43% by another patient and 27% by the Internet. Safety of the operation (43%) was the highest-rated factor in choosing LAGB. LAGB being "least invasive" was most significant in the US (46%), and "surgical safety" in Australia (45%). In the US, Rouxen-Y gastric bypass was preferred due to "lack of a foreign body" (31%) and "inability to cheat" (28%), while in Australia, "dumping" was the most significant reason (50%). Duodenal switch (BPD/DS) was selected in 11% of patients, primarily because of "durability of the weight loss" (51%). Surprisingly, only 1 patient in the US group selected BPD/DS because the pylorus remains intact.

CONCLUSION

Safety and invasiveness had the greatest impact on patient choice for bariatric operation in two different countries. This information may help clinicians better understand their patients' concerns, and their treatment choices.

Endoscopy plays an important preoperative role in bariatric surgery

BACKGROUND

The role of upper endoscopy (EGD) in obese patients prior to bariatric surgery is controversial. The aim of this study was to evaluate the diagnostic yield and cost of routine EGD before bariatric surgery.

METHODS

The medical records of consecutive obese patients who underwent EGD prior to bariatric surgery between May 2000 and September 2002 were reviewed. Two experienced endoscopists reviewed all EGD reports, and findings were divided into 4 groups based on predetermined criteria: group 0 (normal study), group 1 (abnormal findings that neither changed the surgical approach nor postponed surgery), group 2 (abnormal findings that changed the surgical approach or postponed surgery), and group 3 (results that were an absolute contraindication to surgery). Clinically important findings included lesions in groups 2 and 3. The cost of EGD (430.72 US dollars) was estimated using the endoscopist fee under Medicare reimbursement.

RESULTS

During the 28-month study period, 195 patients were evaluated by EGD prior to bariatric surgery. One or more lesions were identified in 89.7% of patients, with 61.5% having a clinically important finding. The prevalence of endoscopic findings using the classification system above was as follows: group 0 (10.3%), group 1 (28.2%), group 2 (61.5%), and group 3 (0.0%). Overall, the most common lesions identified were hiatal hernia (40.0%), gastritis (28.7%), esophagitis (9.2%), gastric ulcer (3.6%), Barrett's esophagus (3.1%), and esophageal ulcer (3.1%). The cost of performing routine endoscopy on all patients prior to bariatric surgery was 699.92 US dollars per clinically important lesion detected.

CONCLUSIONS

Routine upper endoscopy before bariatric surgery has a high diagnostic yield and has a low cost per clinically important lesion detected.

Laparoscopic adjustable gastric band

Only a fraction of morbidly obese patients have come forward for bariatric surgery. This article confirms that the laparoscopic adjustable gastric band (LAGB) is a safe, effective, primary weight-loss operation for morbidly obese patients. The LAGB offers a simple, genuinely minimally invasive approach, with the potential to be attractive to many more patients. The key questions are whether it is effective in the longterm and whether it is safe. The midterm data confirm that, so far, LAGB is living up to its early promise as an effective tool. LAGB surgery is safe, and the change to the pars-flaccida approach will lead to even higher patient satisfaction and lower incidence of band removal.

Impact of patient follow-up on weight loss after bariatric surgery

BACKGROUND

Postoperative follow-up after bariatric surgery is important. Because of the need for adjustments, follow-up after gastric banding may have a greater impact on weight loss than after Roux-en-Y gastric bypass. We reviewed all patients at 1 year after these two operations.

METHODS

During the first year after surgery, laparoscopic adjustable gastric banding (LAGB) patients were followed every 4 weeks and Roux-en-Y gastric bypass (RYGBP) patients were followed at 3 weeks postoperatively and then every 3 months. The number of follow-up visits for each patient was calculated, and 50% compliance for follow-up and weight loss was compared.

RESULTS

Between October 2000 and September 2002, 216 LAGB and 139 RYGBP operations were performed. Of these patients, 186 LAGB patients and 115 RYGBP patients were available for 1-year follow-up. Age and BMI were similar for each group. Overall excess weight loss (EWL) after LAGB was 44.5%. 130 (70%) returned 6 or less times in the first year and achieved 42% EWL. 56 patients (30%) returned more than 6 times and had 50% EWL (P=0.005). Overall %EWL after RYGBP was 66.1%. 53 patients (46%) returned 3 or less times in the first year, achieving 66.1% EWL. 62 patients (54%) returned more than 3 times after surgery and achieved 67.6% EWL (P=NS).

CONCLUSION

Patient follow-up plays a significant role in the amount of weight lost after LAGB, but not after RYGBP. Patient motivation and surgeon commitment for long-term follow-up is critical for successful weight loss after LAGB surgery.

Radiologic assessment of the upper gastrointestinal tract: does it play an important preoperative role in bariatric surgery?

BACKGROUND

The role of upper GI series (UGIS) before bariatric surgery is controversial. The aim of this study was to evaluate the diagnostic yield and cost of routine UGIS prior to bariatric surgery.

METHODS

The medical records of consecutive obese patients who underwent UGIS before bariatric surgery between April 2001 and October 2002 were reviewed. UGIS reports were reviewed by 2 experienced gastroenterologists, and the findings were divided into 4 groups based on predetermined criteria: group 0 (normal study), group 1 (abnormal findings that neither changed the surgical approach nor postponed surgery), group 2 (abnormal findings that changed the surgical approach or postponed surgery), and group 3 (results which were an absolute contraindication to surgery). Clinically important findings included lesions in groups 2 and 3. The cost of an upper GI series (154.80 USD) was estimated from the published 2002 New York State Medicare reimbursement schedule.

RESULTS

During the 18-month study period, 171 patients were evaluated by UGIS prior to bariatric surgery. One or more lesions were identified in 48.0% of patients, with only 5.3% having clinically important findings. The prevalence of radiologic findings using the classification system above was as follows: group 0 (52.0%), group 1 (42.7%), group 2 (5.3%), and group 3 (0.0%). The most common findings identified were esophageal reflux (21.6%) and hiatal hernias (18.7%). The cost of performing routine UGIS on all patients before bariatric surgery was 2,941.20 USD per clinically important finding detected.

CONCLUSIONS

Routine preoperative upper GI series before bariatric surgery had a low diagnostic yield, rarely revealing pathology that changed the surgical approach or postponed surgery.

Controversies in bariatric surgery: evidence-based discussions on laparoscopic adjustable gastric banding

Laparoscopic adjustable gastric banding (LAGB) is a surgical option that involves placing a silicone band circumferentially around the uppermost aspect of the stomach. The band creates a small proximal pouch that empties slowly resulting in early satiety and a decreased appetite. The band is attached to an access port that is secured to the rectus muscle and can be accessed percutaneously in the office with a needle. Injection of saline into the port results in tightening of the band. This is performed on an individual basis according to weight loss and appetite. Band adjustments are required approximately 5-6 times in the first year and 2-3 times in the second year. Weight loss is gradual, averaging 1-2 lb/week during the first 2 years after surgery.

Favorable early results of gastric banding for morbid obesity: the American experience

BACKGROUND

In 2001 a new device for surgical weight loss was approved by the Food and Drug Administration (Lap-Band, Inamed Health). We describe initial results of laparoscopic gastric banding for morbid obesity in two American academic centers.

METHODS

Prospective data was collected on consecutive morbidly obese patients undergoing laparoscopic adjustable gastric banding, and evaluated retrospectively.

RESULTS

Four hundred forty-five consecutive patients underwent Lap-Band from May 2001 through December 2002. The 103 men and 341 women had an average age of 42.1 years (range 17-72 years) and an average body mass index (BMI) of 49.6 kg/m2 (range 35.2-92.2 kg/m2). One operation required conversion to laparotomy due to bleeding; the rest were completed laparoscopically. Mean length of stay was 1.1 days (range 1-10 days). There was one death. Additional complications included band slippage in 14 patients (3.1%), gastric obstruction without slip in 12 (2.7%), port migration in 2 (0.4%), tubing disconnections in 3 (0.7%), and port infection in 5 (1.1%). Two bands (0.4%) were removed due to intraabdominal abscess 2 months after placement. There was one band erosion (0.2%) and no clinically significant esophageal dilation. Ninety-nine patients have 1-year follow-up and have lost an average of 44.3% excess body weight.

CONCLUSION

Laparoscopic gastric banding has much to offer the morbidly obese. We present data showing weight loss rivaling gastric bypass and acceptably low complications. These results parallel success with this device outside America.

Laparoscopic adjustable gastric banding: surgical technique

Laparoscopic adjustable gastric banding is an effective and safe surgical treatment for morbid obesity. Initial experience with the Lap-Band system (Inamed Health, Santa Barbara, California) in the United States and Australia has demonstrated that surgical technique can affect outcomes in terms of weight loss, quality of life, and complication rates. Placement of the gastric band by means of the perigastric technique is associated with high rates of gastric prolapse, food intolerance, and weight loss failure that frequently lead to band explantation. In the pars flaccida technique, band placement higher on the stomach results in the formation of a smaller pouch and lower rates of gastric prolapse, which may contribute to greater weight loss and improved quality of life. This article describes the technical aspects of the pars flaccida approach in the laparoscopic placement of adjustable gastric bands.

Removal of Peri-Gastric Fat Prevents Acute Obstruction after Lap-Band® Surgery

BACKGROUND

Acute postoperative gastroesophageal obstruction is a potential complication after laparoscopic adjustable gastric banding (LAGB). Utilizing the pars flaccida technique may increase the incidence due to the incorporation of perigastric fat, particularly in patients with greater visceral obesity. Removal of peri-gastric fat pads may be necessary to avoid postoperative obstruction. We present our experience of 267 LAGB operations using the LapBand System and the incidence of postoperative obstruction, before and after incorporating routine removal of peri-gastric fat pads.

METHODS

A retrospective review of a prospective database of 267 consecutive Lap-Band placements between July 2001 and November 2002 was conducted.

RESULTS

All operations were completed laparoscopically using the pars flaccida technique, and all patients underwent esophagogram the morning after surgery. From July 2001 to May 2002, 143 Lap-Band placements were performed, with 11 patients (8%) having abnormal postoperative esophagograms. There were 43 males/100 females with mean BMI 48.3 (range 35 to 78.9). Complete esophageal obstruction was seen in 5 of these patients, all of whom underwent laparoscopic revision. Significantly delayed emptying was seen in the 6 remaining patients, who were managed conservatively with intravenous fluids from 2-7 days. In these 11 patients, there were 6 males/5 females with mean BMI 47.1 (range 37.3-57.9). Subsequently, removal of peri-gastric fat pads was routinely performed during Lap-Band placement. From June 2002 to November 2002, there were 43 males/81 females with mean BMI 48 (range 35-79); these 124 Lap-Band placements were performed with no abnormal postoperative esophagograms.

CONCLUSION

Routine removal of peri-gastric fat pads when using the pars flaccida technique for Lap Band surgery appears to prevent postoperative esophageal obstruction.

Serum fat-soluble vitamin deficiency and abnormal calcium metabolism after malabsorptive bariatric surgery

Weight loss after biliopancreatic diversion or duodenal switch is due to decreased calorie absorption secondary to fat malabsorption. Fat malabsorption may also cause essential fat-soluble vitamin deficiencies, which may have severe clinical consequences and alter calcium metabolism. Serum vitamins A, D, E, and K, zinc, parathyroid hormone, corrected calcium, and alkaline phosphatase levels were measured in a cohort of patients who had previously undergone biliopancreatic diversion. Two bariatric surgery units were involved in the study: New York University School of Medicine (New York, NY), and the Wesley Medical Center (Brisbane, Australia). A total of 170 patients completed the study. The incidence of vitamin A deficiency was 69%, vitamin K deficiency 68%, and vitamin D deficiency 63% by the fourth year after surgery. The incidence of vitamin E and zinc deficiency did not increase with time after surgery. The incidence of hypocalcemia increased from 15% to 48% over the study period with a corresponding increase in serum parathyroid hormone values in 69% of patients in the fourth postoperative year. There is a progressive increase in the incidence and severity of hypovitaminemia A, D, and K with time after biliopancreatic diversion and duodenal switch. Calcium metabolism is affected with an increasing incidence of secondary hyperparathyrodisim and evidence of increased bone resorption in 3% of patients. Long-term nutritional monitoring is necessary after malabsorptive operations for morbid obesity.

US experience with the LAP-BAND system

Laparoscopic adjustable gastric banding is the most commonly performed operation for morbid obesity in Europe and Australia and has been shown to result in significant long-term weight loss. The US Food and Drug Administration (FDA)-monitored clinical trial results with the LAP-BAND system (INAMED Health, Santa Barbara, CA) did not reproduce the results of studies performed elsewhere in the world. This article reviews data from the first and second FDA clinical trials as well as data from continuing US clinical experience. Four American surgeons at 4 centers have performed more than 500 LAP-BAND procedures not included in the first 2 FDA clinical trials. Of these patients, 115 have been followed for at least 9 months, and 43 have been followed for at least 12 months. A retrospective analysis of prospective data gathered from these patients is presented. The percent excess weight loss was 35.6% at 9 months and 41.6% at 12 months. The average body mass index decreased from 47.5 to 38.8 in 9 months and from 47.5 to 37.3 in 12 months. There were no deaths related to the insertion of the device. Of 15 complications requiring operative management (13%) in 12 patients, there were 8 port displacements or tubing breaks (7%), 2 elective explantations (2%), 2 cases of gastric prolapse (2%), 1 gastric pouch dilatation (<1%), 1 port abscess (<1%), and 1 hemorrhage (<1%). Clinical experience with the LAP-BAND system in the United States shows the device to be a safe and effective treatment for morbid obesity, with results comparable to the international data. The combination of proper surgical technique and close patient follow-up with frequent band adjustments, performed in a comprehensive bariatric program setting, may make the LAP-BAND system a powerful surgical tool in the treatment of morbid obesity.

Hand-assisted laparoscopic splenectomy for ruptured spleen

Although the laparoscopic technique is an accepted method for elective splenectomy, it is controversial in the setting of trauma. A few reports have described laparoscopic splenorrhaphy for trauma, but none have performed laparoscopic splenectomy for splenic rupture. When the spleen is injured, vascular control and poor visibility due to bleeding present obstacles to laparoscopy. The development of the hand-assist device has helped surgeons make the transition from laparotomy to laparoscopy because of the advantages it provides, such as tactile sensation and immediate vascular control. We utilized these benefits of the hand-assist device to convert a laparoscopic operation to a hand-assisted laparoscopic operation and were thus able to avoid a laparotomy. We report a case in which the hand-assist device was used as an alternative to conversion during a laparoscopic splenectomy for ruptured spleen.

Early results of laparoscopic biliopancreatic diversion with duodenal switch: a case series of 40 consecutive patients

BACKGROUND

Biliopancreatic diversion with duodenal switch (BPD-DS) is an operation which provides one of the greatest maintained weight losses of any bariatric procedure. We looked at the safety and efficacy of laparoscopic BPD-DS for morbid obesity.

METHODS

A 150-200 ml sleeve gastrectomy was created and anastomosed to the distal 250 cm of divided ileum. The median length of the common channel was 100 cm. All patients were prospectively followed up to 12 months.

RESULTS

40 consecutive patients underwent laparoscopic BPD-DS as a primary procedure for morbid obesity. Median patient body mass index (BMI) was 60 kg/m2 (range 42-85 kg/m2). Mean age was 43 +/- 1 years (+/- SEM), with 12 males and 28 females. One patient was converted to open laparotomy (2.5%). Median operative time was 210 +/- 9 minutes (range 110-360 minutes) with a significant correlation between BMI and operative time (p = 0.04). Median length of stay was 4 days (range 3-210 days). There was one 30-day mortality (2.5%). Major morbidities occurred in 6 patients (15%), including 1 anastomotic leak (2.5%), 1 venous thrombosis (2.5%), 4 staple-line hemorrhages (10%) and 1 subphrenic abscess (2.5%). Median follow-up at 6 months (range 1-12 months) resulted in 46% +/- 2% excess weight loss (EWL) and at 9 months 58% +/- 3% EWL.

CONCLUSION

Laparoscopic BPD-DS is a complex, yet feasible, procedure resulting in effective weight loss with an acceptable morbidity. A BMI >65 was associated with increased morbidity and mortality. A long-term study is needed to confirm efficacy and proper patient selection.

Antiangiogenic effects of camptothecin analogues 9-amino-20(S)-camptothecin, topotecan, and CPT-11 studied in the mouse cornea model

Angiogenesis has been correlated with increased invasion and metastases in a variety of human neoplasms. Inadequate inhibition of the growth of tumor microvessels by anticancer agents may result in treatment failure, rated clinically as progressive or stable disease. We have investigated the antiangiogenic properties of three camptothecin analogues, 9-amino-20(S)-camptothecin, topotecan, and camptosar (CPT-11), currently under investigation in clinical settings. Angiogenesis was induced by basic fibroblast growth factor in the cornea of inbred Swiss-Webster mice, with the aim of exploring the suppression of neovascularization by the analogues injected into the mice daily over a period of 6 days. The dose range chosen is known to inhibit, in the mouse model, the growth of various human tumor xenografts or murine tumors. The statistical analysis evaluated the association between the area of neoangiogenesis and the dose of the drugs tested and correlated the effects with observed drug toxicity. It was established that, as the drug doses increased, the area of neovascularization decreased, appearing to approximate a negative exponential curve. 9-Amino-20(S)-camptothecin at 6.89 and 8.26 micromol/kg (2.5 and 3.0 mg/kg) and topotecan at 8.31 micromol/kg (3.5 mg/kg), both drugs being delivered over a 6-day period, had statistically significant reduction (47.2-72.5%) of neoangiogenesis and acceptable toxicity. At higher doses of the two analogues, toxic body-weight losses and deaths were observed. CPT-11 showed statistically significant reduction of neoangiogenesis at a dose of 359 micromol/kg (210 mg/kg) delivered over a 6-day course. Unlike camptothecin analogues, the nontoxic dose of vincristine did not induce a statistically significant inhibition of angiogenesis, and there was no dose-dependent escalation of antiangiogenic effects. The results indicate that camptothecins are most likely cytotoxic against two tumor compartments: in addition to tumor cells of epithelial origin, the drugs act against endothelial cells and prevent the growth of the tumor microvessels. We have hypothesized that treatment failure in some patients is due to incomplete or inadequate inhibition of the microvessel growth by camptothecins. Presumably, an intensive inhibition of the remaining tumor microvasculature in such patients could be achieved by combining a camptothecin with another antiangiogenic anticancer agent or with a highly selective angiogenic inhibitor exerting minimal dose-limiting toxicity. Such treatment by a camptothecin plus a less toxic inhibitor of angiogenesis can improve antitumor efficacy. To validate this concept, preclinical studies followed by clinical trials are planned.

Irsogladine maleate inhibits angiogenesis in wild-type and plasminogen activator-deficient mice

BACKGROUND

The activation of the zymogen plasminogen to the serine protease plasmin by urokinase-type (uPA) and tissue-type (tPA) plasminogen activators (PA) is an important event in a variety of physiologic and pathophysiologic processes in mammals. Enhanced PA activity occurs during angiogenesis and has been correlated in vitro and in vivo with increased tumor aggressiveness and is an indicator of poor prognosis in a variety of tumors in humans. Preliminary studies suggest that the antiulcer drug irsogladine maleate (IM) diminishes PA activity in vitro and may inhibit angiogenesis in vivo. To define the precise mechanism of angiogenesis inhibition by IM in vivo, we tested the ability of IM to blunt angiogenesis in a mouse cornea neovascularization model performed in wild-type and PA-knockout mice.

METHODS

Three days prior to pellet implantation, groups of C57Bl/6 wild-type, uPA-deficient (upA-/-), and tPA-deficient (tPA-/-) mice received IM (300 mg/kg), IM (500 mg/kg), or vehicle (0.5% carboxymethylcellulose) via oral gavage. After 3 days of treatment, hydron polymer-coated pellets of sucrose aluminum sulfate containing 100 ng of basic fibroblast growth factor (bFGF) were inserted into surgically created pockets in the cornea of each mouse. On postoperative day 6, the neovascularization of each cornea was evaluated by a blinded observer using slit lamp microscopy and photographed. Angiogenesis was quantified by calculating vascular area (mm2) +/- SEM using a modified formula for a half ellipse that incorporates calibrated vessel measurements [Vessel length (mm) x Clock hours x pi x 0.2].

RESULTS

IM treatment (300 and 500 mg/kg/day) resulted in a dose-dependent reduction of angiogenesis in wild-type mice by 21 and 45.3% (P < 0.02, P < 0.001), in tPA-deficient mice by 42.6 and 46% (P < 0.001, P < 0.001), and in uPA-deficient mice by 27.2 and 46% (P < 0.05, p < 0.001), respectively. No quantitative differences in neovascularization were observed in either treatment group between transgenic mouse strains. No toxicity was noted in any group.

CONCLUSION

IM inhibits bFGF-induced angiogenesis in wild-type, tPA-knockout, and uPA-knockout mice. The observation that IM significantly diminishes angiogenesis in both PA-deficient mice and wild-type mice suggests that the mechanism of action of IM may be independent of plasminogen activation.

Fibroblast growth factor-2 (FGF-2) induces vascular endothelial growth factor (VEGF) expression in the endothelial cells of forming capillaries: an autocrine mechanism contributing to angiogenesis

FGF-2 and VEGF are potent angiogenesis inducers in vivo and in vitro. Here we show that FGF-2 induces VEGF expression in vascular endothelial cells through autocrine and paracrine mechanisms. Addition of recombinant FGF-2 to cultured endothelial cells or upregulation of endogenous FGF-2 results in increased VEGF expression. Neutralizing monoclonal antibody to VEGF inhibits FGF-2-induced endothelial cell proliferation. Endogenous 18-kD FGF-2 production upregulates VEGF expression through extracellular interaction with cell membrane receptors; high-Mr FGF-2 (22-24-kD) acts via intracellular mechanism(s). During angiogenesis induced by FGF-2 in the mouse cornea, the endothelial cells of forming capillaries express VEGF mRNA and protein. Systemic administration of neutralizing VEGF antibody dramatically reduces FGF-2-induced angiogenesis. Because occasional fibroblasts or other cell types present in the corneal stroma show no significant expression of VEGF mRNA, these findings demonstrate that endothelial cell-derived VEGF is an important autocrine mediator of FGF-2-induced angiogenesis. Thus, angiogenesis in vivo can be modulated by a novel mechanism that involves the autocrine action of vascular endothelial cell-derived FGF-2 and VEGF.

Contribution of vasopressin to blood pressure regulation during hypovolemic hypotension in humans

In animals subjected to hemorrhage, plasma arginine vasopressin concentrations increase to levels sufficient to cause vasoconstriction, thus attenuating the hypotensive response. The purpose of this study was to examine the contribution of vasopressin to blood pressure regulation during hypotension in humans. Hypotension was induced in twelve normal subjects by lower body negative pressure (LBNP) before and after intravenous administration of vasopressin V1 receptor antagonist. Before drug administration, LBNP reduced systolic blood pressure from 125 +/- 4 to 78 +/- 12 mmHg (P < 0.01) as vasopressin concentration increased from 2.9 +/- 0.6 to 17 +/- 6 pg/ml (P < 0.05). After administration of the vasopressin antagonist, LBNP reduced systolic blood pressure from 128 +/- 3 to 89 +/- 11 mmHg (P < 0.01). The hypotensive response to LBNP was not potentiated by inhibiting vasopressin's vasoconstrictive effects (P = NS). Thus hypotension causes marked increases in plasma vasopressin concentration. In contrast to findings in animal studies, however, vasopressin does not contribute to the maintenance of blood pressure during hypotension in humans.

Limb vascular responsiveness to beta-adrenergic receptor stimulation in patients with congestive heart failure

BACKGROUND

In patients with congestive heart failure, the chronotropic and inotropic responses to beta-adrenergic agonists are reduced. It is not known whether desensitization of peripheral beta-adrenoceptors accounts for impaired limb vasodilation in these patients. Accordingly, we studied 14 normal subjects and 13 age-matched patients with congestive heart failure.

METHODS AND RESULTS

To distinguish vasodilation mediated by beta-adrenoceptors and adenylate cyclase from that mediated by stimulation of guanylate cyclase, each subject received intrabrachial artery infusions of isoproterenol (1-100 ng/min) and sodium nitroprusside (0.3-10 micrograms/min), respectively. Forearm blood flow was determined by venous occlusion plethysmography. Maximal vasodilative potential, determined during reactive hyperemia, was reduced in the patients with congestive heart failure. The maximal forearm blood flow response to isoproterenol was comparable in patients with heart failure and in normal subjects (8.0 +/- 1.1 versus 9.2 +/- 1.2 ml/100 ml of tissue/min, respectively, p = NS). Furthermore, the dose-response relation to isoproterenol was similar in both groups. Likewise, the forearm vasodilative response to sodium nitroprusside was preserved in the heart failure group. Plasma concentration of norepinephrine was higher in the patients with heart failure (436 +/- 34 versus 201 +/- 74 pg/ml, p less than 0.01). When both groups were considered, there was no correlation between norepinephrine levels and the maximal forearm blood flow response to isoproterenol (r = 0.10, p = NS).

CONCLUSIONS

We conclude that beta-adrenoceptor desensitization does not occur in the limb vessels of patients with congestive heart failure.