Renal cell carcinoma following bariatric surgery.

BACKGROUND: Obesity, hypertension, smoking, and amphetamine diet pills increase the risk for renal cell carcinoma (RCC). Obesity causes a four-fold increase. We report our 11-year experience with RCC after bariatric operations. METHODS: 5 patients with RCC were identified out of 2,287 bariatric surgical patients since 1993 on retrospective chart review. RESULTS: 4 of the 5 patients were females. At time of their bariatric operation, patients were age 29-52 (43.4) years, weighed 109-158 (129.8) kg, and BMI was 43-60 (49.4). All tumors were incidentally discovered 8-66 (27.4) months postoperatively when the patients weighed 54-94 (71.4) kg, with BMI 21-34 (26.6). Preoperative renal ultrasound obtained within 3 months of the bariatric operation was normal in 4; the other did not have a preoperative study. The latter patient had a vertical banded gastroplasty 12 years before and the RCC was discovered 5 1/2 years later during work-up for a revision. 3 had a distal gastric bypass and 1 underwent adjustable gastric banding. 4 of the patients had a radical nephrectomy and 1 underwent a partial nephrectomy. Tumors were 2.0-8.7 (4.4) cm in size, and all were clear-cell RCC without vascular or extrarenal involvement. None has had recurrence at 3-67 (30.8) months follow-up. 1 patient died from a stroke 18 months later. CONCLUSION: Reversal of obesity following bariatric surgery does not eliminate risk for RCC. Preoperative and annual postoperative ultrasonography may be useful in identifying early stage RCC. Lesions that are not pure cysts must be evaluated with CT scans or MRI. Nephrectomy may be curative.

Topical benzocaine (Hurricaine) induced methemoglobinemia during endoscopic procedures in gastric bypass patients.

BACKGROUND: Methemoglobinemia results from oxidation of ferrous to ferric iron in hemoglobin. In addition to a functional anemia, methhemoglobinemia causes the O2-binding affinity of the remaining O2 sites in the hemoglobin tetramer to increase; essentially shifting the oxyhemoglobin dissociation curve to the left and decreasing O2 delivery. Patients develop profound cyanosis unresponsive to O2 when methemoglobin (MHb) levels exceed 10%. It can be lethal if levels exceed 70%. Benzocaine 20% (Hurricaine) spray, commonly used in endoscopy (EGD) can cause methemoglobinemia. We report our experience. METHODS: Two patients out of >1,000 EGDs in 4 yrs developed methemoglobinemia. RESULTS: Patient 1: 34 F, BMI 46, open distal gastric bypass. Patient 2: 26 F, BMI 49, laparoscopic proximal gastric bypass. Both had nausea and vomiting from stomal stenosis requiring EGD for which benzocaine 20% spray was used. Severe cyanosis (despite pulse oximetry readings of 86% and 89%), dyspnea and tachycardia, were seen within 13 and 7 minutes. They were unresponsive to O2, despite being awake and conversant after complete reversal of sedatives. MHb levels were 35.6% and 18.8% (normal <1%). Patients dramatically improved after 1% methylene blue at 1-2 mg/kg IV over 5 minutes. MHb levels dropped to 2.3% and 0.8 % within 150 and 110 minutes. Neither patient had any evidence of pulmonary embolism or DVT or G6PD deficiency. CONCLUSION: Topical benzocaine 20% (Hurricaine) spray used in EGDs gets absorbed and can cause methemoglobinemia. Sprays should be limited to 1 second. Prompt treatment with 1% methylene blue IV can be life-saving.

Critical extreme anterior slippage (paragastric Richter's hernia) of the stomach after laparoscopic adjustable gastric banding: early recognition and prevention of gastric strangulation.

BACKGROUND: We report an unusual complication after Lap-Band placement characterized by herniation of the anterior stomach through the band. METHODS: Group 1 - 105 patients: Operated elsewhere (prior to US FDA approval) and followed by us; perigastric technique was used in 74 and pars flaccida in 31. Group 2 - 218 patients: Operated by us since August 2001 using the pars flaccida approach only. 4 patients with this unusual problem were identified. RESULTS: Patients were all female, with age 37.5 (3343) yr, weight 143.7 (123-167) kg, and BMI 54 (45-65). Onset occurred at 9 (5-16) months, with weight loss: 38.5 (27-53) kg and %EWL 47.3 (31-54)%. All had sudden nausea, vomiting and epigastric abdominal pain that persisted despite emptying the band. None of these symptoms were related to a recent band adjustment. CT scan showed a paragastric Richter's hernia of the stomach underneath the band. At exploration, the band was in the normal location. 3 patients from Group 2 had Richter's hernia of the anterior stomach through the band; reduction of the stomach with closure of the defect was performed. One patient from group 1 had gangrene of the entrapped stomach, resulting in band removal and gastrectomy. CONCLUSION: Lap-Band patients with sudden nausea, vomiting and abdominal pain, when not relieved by emptying the band, should undergo a CT scan. If a traditional slippage is not confirmed, paragastric Richter's hernia of the stomach through the band should be suspected. Immediate exploration with reduction of the stomach and closure of the defect can salvage the stomach and the band. Gastro-gastric sutures must completely close the space underneath the band to prevent this complication.

Computed tomography patterns in small bowel obstruction after open distal gastric bypass.

BACKGROUND: Life-threatening small bowel obstruction (SBO) after Roux-en-Y gastric bypass can present with surprisingly minimal laboratory and plain x-ray findings. Based on a 10-year (1994-2003) experience of 1,409 open distal gastric bypasses, we present clinical and radiological findings in 29 patients with unusual forms of bowel obstruction. METHODS: A retrospective chart review was conducted. A radiologist experienced in reviewing these in gastric bypass patients reviewed all computed tomography (CT) scans. RESULTS: CT findings: The normal appearance and 7 recurring patterns of small bowel obstruction were identified. These include: 1) intussusception, 2) internal hernia through Petersen's space, 3) through Petersen's space and the mesenteric defect at enteroenterostomy, 4) through the mesenteric defect from the entero-enterostomy, 5) isolated biliary limb obstruction, 6) segmental non-anastomotic ischemia, and 7) internal hernia through bands. CLINICAL FINDINGS: 1 had peritonitis, and 1 had free air on plain film. WBC count was normal in 20/27 patients (74%) including 5/6 (83%) with dead bowel. 9/14 patients (62%) had "non-specific" findings on x-rays. 7 of these had an internal hernia (2 with volvulus and 2 with dead bowel), 1 had biliopancreatic limb obstruction, and 1 had peritonitis. CONCLUSION: Patients with SBO after distal gastric bypass may present with vague complaints and confusing laboratory and non-specific findings on x-rays. Delayed diagnosis can have catastrophic consequences. CT imaging with oral and intravenous contrast can be life-saving, and should be obtained in all gastric bypass patients with abdominal pain, particularly when all other parameters seem "normal". Unexplained abdominal pain should prompt exploration.

The Lap-Band system in a North American population.

BACKGROUND: European and Australian results with laparoscopic adjustable gastric banding (LAGB) using the Lap-Band (Inamed Health, Santa Barbara, CA) have been impressive, with over 100,000 procedures completed at this writing. However, prior to U.S. FDA approval in June 2001, U.S. patients had to travel out of the U.S. for this procedure. This study reports on a series of U.S. patients who requested off-shore referral for LAGB placement. METHODS: 105 U.S. patients were implanted with the Lap-Band System in Mexico by one surgeon in a private practice. 70% were implanted with the perigastric approach, while the final 30% were implanted using the pars flaccida approach. Routine postoperative visits, including band adjustments, were completed in a private U.S. clinic where medical staff performed frequent small adjustments as necessary to optimize results. Data were collected from concurrent and retrospective chart reviews and from telephone interviews. Summary statistics provided for baseline measures included mean +/- standard deviation. Postoperative measures of weight loss included mean +/- standard error. RESULTS: Weight loss results were comparable to international results: 61% EWL at 12 months (n=50), 75% EWL at 24 months (n=37), 72% EWL at 36 months (n=24), and 60% EWL at 48 months (n=7). There were few major complications. CONCLUSION: Attention to patient management is essential to success, and this study found that appropriately-managed U.S. LAGB patients can be as successful as their international counterparts. Frequent follow-up delivered by a bariatric team with easy access to band adjustments is essential.