Hormonal and dietary influences on true fractional calcium absorption in women: role of obesity

The goal in this study was to examine the hormonal and dietary predictors of true fractional Ca absorption (TFCA) in adult women and to determine whether TFCA differs due to body weight. Results showed that TFCA is higher in obese individuals and dietary fat, estradiol, and 1,25-dihydroxy vitamin D are the most significant positive predictors of TFCA in adult women.

INTRODUCTION

Calcium absorption is an important determinant of calcium balance and is influenced by several factors. Previous studies have identified that age, intake of protein, fat and fiber, and hormones such as 1, 25-dihyroxyvitamin D (1,25(OH)(2)D(3)) influence absorption. The determinants of TFCA using the double isotope method, the gold standard estimate of absorption, have not been examined previously in adult women nor has the role of obesity been addressed.

METHODS

In this study, we examined the hormonal and dietary predictors of TFCA in adult women with a wide range of age, body weights, and nutrient intake. TFCA was measured using dual stable isotope ((42)Ca and (43)Ca) technique. Serum was analyzed for bone-regulating hormones, and dietary information was obtained through food records. The independent dietary factors and hormonal predictors (25-hydroxyvitamin D, 1,25(OH)(2)D(3), parathyroid hormone, and estradiol) of TFCA were analyzed using multiple regression analysis.

RESULTS

Two hundred twenty-nine women aged 54 ± 11 years old (24-75 years) and with BMI of 31 ± 7.0 kg/m(2) were eligible and were categorized into tertiles of body mass index (BMI) into leaner, overweight, and obese. In the entire group of women, total fat intake, estradiol, and 1,25(OH)(2)D(3) are significant positive predictors (p < 0.05). As expected, age is a significant negative predictor of TFCA (R (2) = 26%). TFCA is higher in obese women compared to non-obese women (p < 0.05).

CONCLUSION

Together, these data show that dietary fat is the most significant positive predictor of TFCA which may have implications for dietary intake for non-obese individuals who are more likely to have lower and potentially compromised Ca absorption.

Gastric bypass

Nearly all morbidly obese patients with satisfactory postoperative weight loss experience substantial improvement in the quality of their lives. Improved health status is characterized by increased exercise tolerance and improvement or resolution of obesity-related comorbidities. Improvement of obesity-related medical problems (discussed in the article by Klein elsewhere in this issue) is a primary goal of gastric bypass. The patient's ability to interact with others in social situations is also enhanced. At present, RYGB may be the only bariatric operation that has produced durable long-term weight loss at an acceptable level of risk.

Gastric bypass surgery in adolescents with morbid obesity

OBJECTIVE

The objective was to review retrospectively all patients undergoing bariatric surgery at a large university medical center.

METHODS

Ten adolescents 17 years or younger underwent gastric bypass surgery; 7 of 10 adolescents had severe obesity-related morbidities. Follow-up >1 year was present in 9 of 10 adolescents.

RESULTS

The average weight before surgery was 148 +/- 37 kg. Postoperative recovery was uneventful in all adolescents; 9 of 10 adolescents had weight loss in excess of 30 kg (mean weight loss was 53.6 +/- 25.6 kg). Obesity related morbidities resolved in all adolescents. Five adolescents had mild iron deficiency anemia, and 3 adolescents had transient folate deficiency. Late complications requiring operative treatment occurred in 4 of the adolescents.

CONCLUSION

Gastric bypass surgery was an effective method for weight reduction in morbidly obese adolescents. The procedure was well tolerated, with few unanticipated side effects. Gastric bypass remains a last resort option for severely obese adolescents for whom other dietary and behavioral approaches to weight loss have been unsuccessful.

Regulation of the leptin content of obese human adipose tissue

The objective of this study was to determine whether obese human adipose tissue contains preformed stores of leptin and their relationship to secreted leptin. Detergent increased detectable leptin by about twofold, suggesting that leptin is stored in a membrane-bound location. Subcutaneous tissue leptin was approximately 1.6-fold higher than omental, paralleling known differences in leptin secretion and expression. The amount of leptin secreted during a 3-h incubation was similar to that of extractable tissue leptin. Tissue leptin levels were maintained over the incubation. Inhibition of protein synthesis decreased tissue leptin content but did not decrease leptin secretion until after 3 h of incubation. Culture of adipose tissue for 2 days with the combination of insulin and dexamethasone, but not with either hormone alone, increased tissue leptin content about twofold in both depots. Although insulin did not affect tissue leptin content, it potentiated leptin secretion (as a % of tissue stores). These data suggest that adipose tissue leptin storage and secretion per se are regulated. Regulation of the release of preformed leptin may modulate serum leptin levels in obese humans.

Assessment of eating disorders in bariatric surgery candidates: self-report questionnaire versus interview

OBJECTIVE

To compare the Eating Disorder Examination (EDE), an investigator-based interview for the assessment of the specific psychopathology of eating disorders, with the EDE-Q, a self-report questionnaire based directly on it.

METHOD

Ninety-eight morbidly obese gastric bypass surgery candidates were administered both instruments.

RESULTS

The four subscale scores (Restraint, Eating Concern, Weight Concern, and Shape Concern) generated by the EDE and EDE-Q were significantly correlated, although the questionnaire scores were significantly higher. Eating Concern and Shape Concern exhibited the lowest levels of agreement. Frequency of binges (objective bulimic episodes) as rated by the EDE and EDE-Q was significantly correlated and was not significantly different. However, variability in ratings contributed to only modest agreement with respect to classification of patients as binge eaters.

DISCUSSION

Overall, there were lower levels of agreement between the EDE and EDE-Q than have been previously found in other samples.

Staphylococcal enterotoxin B induces potent cytotoxic activity by intraepithelial lymphocytes

In food poisoning, Staphylococcus aureus secretes staphylococcal enterotoxin B (SEB), a superantigen that causes intense T-cell proliferation and cytotoxicity. The effects of SEB on lytic activity by human intestinal intraepithelial lymphocytes (IEL) were investigated. Jejunal IEL, from morbidly obese individuals undergoing gastric bypass operations, were tested for SEB-induced cytotoxicity against C1R B-lymphoblastoid cells, HT-29 adenocarcinoma cells, or CD1d-transfected cells using the 51Cr-release assay. Fas and Fas ligand expression were detected by immunofluorescence and flow cytometry and soluble ligand by enzyme-linked immunosorbent assay (ELISA). In the presence of SEB, IEL became potently cytotoxic against C1R cells and interferon-gamma (IFN-gamma)-precultured HT-29 cells, causing 55+/-10% and 31+/-6% lysis, respectively, greater than that by phytohaemagglutinin (PHA)-, interleukin-2 (IL-2)-, or anti-T-cell receptor (TCR)-activated IEL. SEB-stimulated peripheral blood (PB) CD8+ T cells lysed similar numbers of C1R cells but fewer HT-29 cells (53+/-13% and 8+/-5%, respectively). IEL killing of C1R cells involved interaction of major histocompatibility complex (MHC) class II with TCR, CD2 with CD58, and CD11a with CD54, and was perforin mediated. SEB-induced IEL lysis of HT-29 cells, in contrast, was caused by an unknown target cell structure, not MHC class II or CD1d, and resulted from a combination of perforin and Fas-mediated events. The potent cytotoxic activities of IEL promoted by SEB utilize two different mechanisms, depending on the surface receptors expressed by the target cells.

Lipid risk profile and weight stability after gastric restrictive operations for morbid obesity

There are no longitudinal data that address weight loss stability and lipid levels in bariatric surgical patients. The goal of this study was to determine whether weight regain adversely affected reduction in lipid levels after gastric bariatric operations. Of 651 consecutive patients undergoing gastric restrictive surgery for morbid obesity, 227 (35%) had increased serum levels of total cholesterol (TC), triglycerides, or both preoperatively. High-density lipoprotein cholesterol (HDL-C) levels were subnormal (</=35 mg/dl) in 45 (20%) of the hyperlipidemic patients. Fasting lipid profiles were determined at 6-month intervals postoperatively. This series included the following three operations: gastroplasty (GP; N = 13), standard Roux-en-Y gastric bypass (RYGB; N = 205), and distal Roux-en-Y gastric bypass (DRY; N = 9). By 6 months postoperatively, patients had a >/=15% mean reduction in TC and a >/=50% mean reduction in triglycerides, both of which were significant in comparison with preoperative levels (P </=0.05). Mean HDL-C levels had increased significantly vs. preoperative levels by 12 months postoperative y (P <0.05) and continued to increase through 5 years. By 18 months both HDL-C and TC were significantly lower after DRY than after GP or RYGB. In 91 patients who were followed for 2 years or longer (mean 48 +/- 25 months), mean excess weight loss was 55% with mean body mass index reduced from 48 to 33 kg/m(2). This group was divided into patients whose weight remained stable (N = 54) and patients who regained >/=15% of their lost weight or lost less than 50% of excess weight (N = 37). Although mean excess weight loss and body mass index were significantly different between the two groups (P <0.0001) at 2 years, there was no difference in the lipid profile (TC/HDL) between the two groups at any interval through 5 years. These results show that abnormal lipid profiles can be permanently improved after gastric bariatric surgery and are not adversely affected by mediocre weight loss or regaining >/=15% of lost weight. DRY appears to be a superior operation for TC reduction in comparison with GP and RYGB.

Efficacy and safety of patient-controlled analgesia for morbidly obese patients following gastric bypass surgery

BACKGROUND

Adequate postoperative pain control is important to reduce potential cardiopulmonary complications. It is often difficult to determine dosages of narcotics for morbidly obese patients following Roux-en-Y gastric bypass (RYGBP) due to respiratory depression. Individualization of analgesic therapy, patient-controlled analgesia (PCA), can provide optimal dosage for pain control and minimize the side-effects.

METHOD

25 morbidly obese patients who received PCA with morphine sulfate following RYGBP. PCA settings we re as follows: morphine, 20 microg/kg of ideal body weight, 10-minute lock out interval and 80 % of a calculated amount for a 4-hour limit. W e measured arterial blood gas, heart rate, mean arterial pressure, arterial oxygen saturation, respiratory rate, opioid amount, patient satisfaction, visual analog pain scale (VAS), and the incidence of nausea, vomiting, pruritus and sedation.

RESULTS

Average morphine usage was 44.2+/-28.7 mg during the day of surgery (DOS); 49.1+/-27.4 mg during POD (postoperative day) #1; and 36.6+/-22.8 mg during POD#2 (p < 0.01). 24 patients were satisfied with their pain control on POD#1. VAS was 5.4+/-2.1 on the day of surgery, but remained below 4 thereafter. Arterial oxygen saturation and vital signs were maintained without significant changes. 5 patients experienced mild sedation on the day of surgery and 3 patients experienced mild sedation on POD#1. 1 patient experienced nausea and vomiting and 4 patients had pruritus; however, none required treatment.

CONCLUSION

PCA is safe and effective for morbidly obese patients following RYGBP.

Integrin alpha1beta1 (VLA-1) mediates adhesion of activated intraepithelial lymphocytes to collagen

Intraepithelial lymphocytes (IELs) from human intestinal epithelium are memory CD8+ T cells that bind to epithelial cells through human mycosal lymphocyte (HML)-1 and to mesenchymal cells through very late activation antigen-4 (VLA-4). Their binding of extracellular matrix proteins and the mechanism involved were tested. Activated 51Cr-labelled lymphocytes were incubated in protein-coated microwells with various additives. After washing, the adherent cells were detected by radioactivity. The percentages of activated IELs that bound to collagen types I and IV were 20 and 31%, respectively; fewer bound to fibronectin or laminin. Compared to interleukin-2-activated peripheral blood CD8+ T lymphocytes, more IELs bound collagen IV and fewer bound fibronectin. IEL adhesion to collagen (but not fibronectin or laminin) was up-regulated by antibody ligation of CD2 or by protein kinase C stimulation by phorbol ester; staurosporine reduced binding, while herbimycin, phytohaemagglutinin and CD3 ligation had no effect. Antibody-blocking of integrin VLA-1 subunits alpha1 (CD49a) and beta1 (CD18) inhibited adhesion to collagen type I by 82+/-6% and to type IV by 94+/-1% (P<0.001), implicating VLA-1 as the main collagen receptor for IELs. Cell adhesion was dependent on extracellular divalent cations, a characteristic event of VLA-1 never before shown for IELs: manganese and magnesium ions supported binding in a dose-dependent manner; calcium ions inhibited their effectiveness. Therefore, IELs bind collagen through integrin alpha1beta1 after protein kinase C activation. Adhesion is modulated by divalent cations.

Survey of vitamin and mineral supplementation after gastric bypass and biliopancreatic diversion for morbid obesity

BACKGROUND

The authors investigated whether practice patterns of bariatric surgeons correlate with published data regarding metabolic deficiencies after Roux-en-Y gastric bypass (RYGB) and biliopancreatic diversion (BPD).

METHODS

109 surgeons completed a questionnaire to determine use of supplements and frequency of lab tests.

RESULTS

Regarding supplements routinely prescribed after RYGB, 96% of surgeons gave multivitamins, 63% gave iron, and 49% gave vitamin B12. After BPD, 96% of surgeons gave multivitamins, 67% gave iron, 42% gave vitamin B12, 97% gave calcium, 63% gave fat-soluble vitamins, and 21% gave protein supplements. Regarding laboratory tests obtained routinely after RYGB, 95% of surgeons do complete blood counts, 56% do iron determinations, 66% do vitamin B12 determinations, 58% do folate determinations, 76% do electrolyte determinations, and 8% test for proteins. After BPD, 96% of surgeons do complete blood counts, 80% do iron determinations, 67% do vitamin B12 determinations, 71% do folate determinations, 88% do electrolyte determinations, 84% do protein determinations, and 46% test for fat-soluble vitamins. Regarding frequency of blood tests, after RYGB, 22% of surgeons obtain them after 3 months, 33% after 6 months, and 41% after 12 months; 4% do not routinely obtain postoperative laboratory tests. After BPD, 46% of surgeons obtain them after 3 months, 33% after 6 months, and 16% after 12 months; one does not obtain laboratory tests. Surgeons estimated these deficiencies after RYGB: 16% iron, 12% vitamin B12, 14% anemia, 5% protein, and 3% calcium. They estimated these deficiencies after BPD: 26% iron, 11% vitamin B12, 21% anemia, 18% protein, 16% calcium, and 6% fat-soluble vitamins. The estimated incidence of deficiencies after RYGB was considerably lower than the published incidence. Unnecessary tests were commonly performed (electrolytes after RYGB).

CONCLUSION

Despite wide variations in the performance of laboratory tests and the use of supplements, the practice patterns of most surgeons protect patients from developing severe metabolic deficiencies after RYGB and BPD.

Effects of bariatric surgery on binge eating and related psychopathology

The Beck Depression Inventory (BDI), the Three-Factor Eating Questionnaire (TFEQ), and the Eating Disorder Examination (EDE) were administered to 50 morbidly obese patients before and after gastric bypass surgery. Subjects were classified as non-binge or binge eaters prior to surgery. Though the two groups differed markedly before operation, they were largely indistinguishable 4 months afterward. All binge eating had ceased and mood had improved markedly. TFEQ Restraint scores increased, and Disinhibition and Hunger scores decreased. EDE Eating Concern, Shape Concern, and Weight Concern scores dropped. EDE Restraint scores decreased in non-binge eaters and increased in binge eaters. The overall findings indicate that gastric bypass surgery had a positive short-term impact on non-binge and binge eaters alike.

Effect of aging on intestinal ischemia and reperfusion injury

Intestinal ischemia/reperfusion (I/R) is a serious disorder that is prevalent in elderly patients. Reactive oxygen species are implicated in the pathogenesis of intestinal I/R injury. Reactive oxygen species are also implicated in cellular senescence and aging. To test the hypothesis that aging exacerbates intestinal I/R injury, the effects of intestinal I/R on tissue injury were compared between young (3 month old) and aged (12 month old) mice. Intestinal ischemia was induced by occluding the superior mesenteric artery with a microbulldog clamp. Reperfusion was initiated by removing the clamp. Mortality due to intestinal ischemia followed by reperfusion was significantly higher in aged mice. There were no differences in the baseline levels of malondialdehyde or myeloperoxidase activity (indicators of lipid peroxidation and neutrophil infiltration, respectively) between young and aged mice. Although intestinal I/R caused a significant increase in malondialdehyde levels and myeloperoxidase activity in aged mice, similar increases were also observed in young mice. There were no significant differences in the activities of antioxidant enzymes including superoxide dismutase, glutathione peroxidase and catalase between young and aged mice that underwent sham operation. Intestinal I/R caused a significant decrease in catalase activity only in aged mice. In conclusion, our results indicate that aged mice are more susceptible to mortality due to intestinal I/R and that an age-dependent decrease in catalase activity may contribute to the observed mortality.

Performance standards in bariatric surgery

A bariatric surgeon is a fully trained general or gastrointestinal surgeon who has demonstrated specialized knowledge in the management of patients who suffer from morbid obesity and its complications. In addition to appropriate formal surgical training, preceptorships with experienced surgeons, preferably members of international bariatric societies, are highly desirable. Active participation in meetings of these societies, continuing medical education and knowledge of the current literature are necessary to maintain the required skills to treat these complex patients. Bariatric surgery should be performed at institutions that provide the necessary equipment, facilities and support systems for this particular population. When analysing outcomes of obesity surgery, long-term weight loss reports should include the number of patients followed and the time period of follow-up. Complications and re-operations should be presented, as well as modifications of techniques when various operations are compared. Weight loss should not be the only criterion used to define success or failure. Objective assessment of improvement in medical conditions related to obesity, and reliable measurements of quality of life after surgery should also be included in the final outcome analysis.

Gastrointestinal surgery for obesity

Surgery is becoming an increasingly common method for treatment of morbid obesity in the United States. This text includes the presentation of a typical morbidly obese man with a number of obesity related comorbidities who was treated with a modification of Roux-en-Y gastric bypass. Subsequently, the gastrointestinal operations currently in use as treatment for morbid obesity are discussed. Preoperative and postoperative care for this patient population is discussed briefly. The results of the various procedures are also discussed in terms of both complications and improvement of medical comorbidities.

Leptin expression in adipose tissue from obese humans: depot-specific regulation by insulin and dexamethasone

We investigated the in vitro regulation of leptin expression in adipose tissue from severely obese women and men before and after culture with insulin (7 nM) and/or dexamethasone (25 nM). Leptin mRNA and leptin secretion were two- to threefold higher in subcutaneous vs. omental adipose tissue before culture. Dexamethasone transiently increased leptin mRNA approximately twofold in both depots after 1 day of culture [P < 0.01 vs. basal (no hormone control)], but leptin secretion was only increased in omental adipose tissue (P < 0.005 vs. basal). Insulin did not increase leptin mRNA in either depot but increased leptin secretion approximately 1.5- to 3-fold in subcutaneous tissue throughout 7 days of culture (P < 0.05 vs. basal). The combination of insulin and dexamethasone increased leptin mRNA and leptin secretion approximately two- to threefold in both depots at day 1 (P < 0.005 vs. basal or insulin) and maintained leptin expression throughout 7 days of culture. We conclude that insulin and glucocorticoid have depot-specific effects and function synergistically as long-term regulators of leptin expression in omental and subcutaneous adipose tissue from obese subjects.

Are vitamin B12 and folate deficiency clinically important after roux-en-Y gastric bypass?

Although iron, vitamin B12, and folate deficiency have been well documented after gastric bypass operations performed for morbid obesity, there is surprisingly little information on either the natural course or the treatment of these deficiencies in Roux-en-Y gastric bypass (RYGB) patients. During a 10-year period, a complete blood count and serum levels of iron, total iron-binding capacity, vitamin B12, and folate were obtained in 348 patients preoperatively and postoperatively at 6-month intervals for the first 2 years, then annually thereafter. The principal objectives of this study were to determine how readily patients who developed metabolic deficiencies after Roux-en-Y gastric bypass responded to postoperative supplements of the deficient micronutrient and to learn whether the risk of developing these deficiencies decreases over time. Hemoglobin and hematocrit levels were significantly decreased at all postoperative intervals in comparison to preoperative values. Moreover, at each successive interval through 5 years, hemoglobin and hematocrit were decreased significantly compared to the preceding interval. Folate levels were significantly increased compared to preoperative levels at all time intervals. Iron and vitamin B12 levels were lower than preoperative measurements and remained relatively stable postoperatively. Half of the low hemoglobin levels were not associated with iron deficiency. Taking multivitamin supplements resulted in a lower incidence of folate deficiency but did not prevent iron or vitamin B12 deficiency. Oral supplementation of iron and vitamin B12 corrected deficiencies in 43% and 81% of cases, respectively. Folate deficiency was almost always corrected with multivitamins alone. No patient had symptoms that could be attributed to either vitamin B12 or folate deficiency Conversely, many patients had symptoms of iron deficiency and anemia. Lack of symptoms of vitamin B12 and folate deficiency suggests that these deficiencies are not clinically important after RYGB. Conversely, iron deficiency and anemia are potentially serious problems after RYGB, particularly in younger women. Hence we recommend prophylactic oral iron supplements to premenopausal women who undergo RYGB.

Prophylactic iron supplementation after Roux-en-Y gastric bypass: a prospective, double-blind, randomized study

OBJECTIVE

To determine whether prophylactic oral iron supplements (320 mg twice daily) would protect women from iron deficiency and anemia after Roux-en-Y gastric bypass.

DESIGN

Prospective, double-blind, randomized study in which 29 patients received oral iron and 27 patients received a placebo beginning 1 month after Roux-en-Y gastric bypass.

SETTING

Tertiary care medical center.

PATIENTS AND INTERVENTIONS

Complete blood cell count and serum levels of iron, total iron binding capacity, ferritin, vitamin B12, and folate were determined preoperatively and at 6-month intervals postoperatively in 56 menstruating women who had Roux-en-Y gastric bypass.

MAIN OUTCOME MEASURE

Incidence of iron deficiency and other hematological abnormalities in each treatment group.

RESULTS

Hemoglobin, hematocrit, and vitamin B12 levels were significantly decreased compared with preoperative values in both groups. Conversely, folate levels increased significantly over time in both groups. Oral iron consistently prevented development of iron deficiency in the iron group. Ferritin levels did not change significantly in the iron group. However, in placebo-treated patients, ferritin levels 2 years postoperatively were significantly decreased compared with preoperative levels. There was no difference in the incidence of anemia between the 2 groups. However, the incidence of microcytosis was substantially greater (P=.07) in placebo-treated than iron-treated patients.

CONCLUSIONS

Prophylactic oral iron supplements successfully prevented iron deficiency in menstruating women after Roux-en-Y gastric bypass but did not consistently protect these women from developing anemia. On the basis of these results we now routinely recommend prophylactic iron supplements to menstruating women who have Roux-en-Y gastric bypass.

Binge eating in bariatric surgery patients

OBJECTIVE

Eating behavior, attitudes toward eating and body weight and shape, and depression were assessed in a sample of 64 morbidly obese gastric bypass surgery candidates.

METHOD

The Beck Depression Inventory (BDI), the Three-Factor Eating Questionnaire (TFEQ), and the Eating Disorder Examination (EDE) were administered at the first preoperative visit.

RESULTS

Twenty-five subjects (39%) reported at least one binge episode per week on average over the 3 months prior to seeking treatment. Binge eaters had significantly higher TFEQ Disinhibition and Hunger scores than nonbinge eaters. Binge eaters also differed from nonbinge eaters in terms of attitudes toward eating, shape, and weight.

DISCUSSION

A significant number of gastric bypass surgery candidates report binge eating. The findings are consistent with other studies showing binge eaters to be a distinctive subgroup of the obese.

Unsuspected cirrhosis discovered during elective obesity operations

OBJECTIVE

To determine the incidence and outcome of cirrhosis encountered unexpectedly during gastric bariatric operations.

DESIGN

A cohort study.

SETTING

A tertiary care center.

PATIENTS

One hundred twenty-five patients in whom cirrhosis was discovered during gastric bariatric operations. Cirrhosis may have been caused by severe obesity in 93 (74%) of the patients.

INTERVENTIONS

A questionnaire survey of bariatric surgeons worldwide, including one of us (R.E.B.).

RESULTS

One hundred twenty-six (52%) of the 243 surgeons responded to the survey. Planned bariatric operations were performed in 91 (73%) of the cases. Seventeen (14%) of the remaining cases were closed after the discovery of cirrhosis. There were no intraoperative deaths. However, the perioperative mortality rate was 4% and there were 7 late deaths, 6 due to complications of liver disease. Eleven other patients are described as alive with progressive hepatic dysfunction. The remaining 50 patients are "alive and well." The survey also included opinion questions. Regarding the appropriate operation to perform after discovering cirrhosis, 40% replied "perform liver biopsy only and close"; the remaining 60% would perform a bariatric procedure. Regarding bariatric operations that can be safely performed in patients with cirrhosis, 59% would perform banded gastroplasty, 39% would perform standard Roux-en-Y gastric bypass, 5% would perform biliopancreatic bypass, and 27% would perform none of the above.

CONCLUSION

Although operative mortality is higher in cirrhotic vs other bariatric patients, most surveyed surgeons believe that gastric restrictive operations can be performed safely in this group of patients.

Comparison of ischemic and reperfusion injury in canine bowel viability assessment

The purpose of these experiments was to evaluate two methods of bowel viability assessment in two distinct models of intestinal ischemia. Bowel viability was assessed in 32 dogs by means of three methods: (1) a probe that quantified the intestinal electromyographic (EMG) measurements in millivolts (mV), (2) Doppler ultrasonography, and (3) perfusion fluorometry, which quantified serosal blood flow in indexed dye fluorescence units (dfi). Ischemia was created using one of two methods: (1) a chronic model in which the blood supply to 40 cm of ileum was ligated and viability assessed 24 hours later, or (2) an acute model in which the main superior mesenteric artery was occluded for 3 1/2 hours and then released. Viability parameters were assessed every 5 minutes for 30 minutes after release. After viability assessment was completed, the ischemic bowel was resected and anastomosed at the site where the EMG measurements approximated 50% of the values obtained in normal bowel. In the chronic group 3 of 20 dogs died of necrosis in contrast to none of 12 dogs in the acute reperfusion group. In the acute model EMG values steadily increased after reperfusion, stabilizing by 15 minutes after release. Mean EMG values at 15 through 30 minutes after release were significantly greater than the 5- and 10-minute postrelease and prerelease values, suggesting that the electromyogram is affected by reperfusion. Conversely, postrelease fluorometry measurements rapidly increased to levels that exceeded measurements obtained in normal bowel. There was a significant difference in the number of audible Doppler signals in the marginal artery of survivors of the acute vs. the chronic model. Fluorometry measurements in survivors of the acute model (99+/-9 dfi) were significantly greater than measurements in the chronic model (54+/-4 dfi, P<or=0.004). Conversely, intermodel differences in the EMG measurements were not significant. These results show significant differences in the magnitude of ischemic damage induced by reperfusion vs. mesenteric ligation, which had a significant impact on the objective blood flow measurements that were used to predict bowel viability. The results also suggest that intestinal reperfusion injury in dogs has a negligible impact on bowel survival.

Evaluation of quantitative approaches to assessment of bowel viability

Predicting the survivability of intestine that has been made ischemic by impairment of blood flow is a major unsolved problem in gastrointestinal surgery. Currently, the surgeon must rely on qualitative, often subjective assessments that are known to have marginal reliability. This review describes various approaches to quantitatively assess the survivability of intestine compromised by ischemic disease. Much of the review centers on work done in the authors' laboratory to evaluate various approaches to predicting long-term survival and to develop new assessment parameters. Towards that end the authors have designed and developed techniques based on intestinal contractility and myoelectric activity (the intestinal EMG). Their evaluations of these and other methods of viability assessment utilize a highly representative canine model of intestinal ischemia that closely follows the development and treatment of ischemic intestinal disease in humans. Results to date suggest that the myoelectric measurements are more reliable than parameters based on blood flow or visual evaluation in terms of predicting bowel survival. However, improvements in instrumentation and technique are needed before this approach is suitable for clinical use.

Intestinal ischemia and reperfusion injury in transgenic mice overexpressing copper-zinc superoxide dismutase

Superoxide dismutase (SOD) scavenges oxygen radicals that are implicated in the pathogenesis of intestinal ischemia-reperfusion injury. The effect of intestinal ischemia and reperfusion was investigated in transgenic mice overexpressing human Cu-Zn SOD. Ischemia was induced by occluding the superior mesenteric artery. Myeloperoxidase activity was determined as an index of neutrophil infiltration, and malondialdehyde levels were measured as an indicator of lipid peroxidation. Forty-five minutes of intestinal ischemia followed by 4 h of reperfusion caused an increase in intestinal levels of malondialdehyde in both nontransgenic and transgenic mice, but the concentration of malondialdehyde was significantly greater in nontransgenic mice. Intestinal ischemia-reperfusion also caused an increase in intestinal and pulmonary myeloperoxidase activity in nontransgenic and transgenic mice, but the transgenic mice had significantly lower levels of myeloperoxidase activity than nontransgenic mice. Transgenic mice had higher levels of intestinal SOD activity than nontransgenic mice. There were no significant differences in the catalase or glutathione peroxidase activities. In conclusion, our study demonstrates that the overexpression of SOD protects tissues from neutrophil infiltration and lipid peroxidation during intestinal ischemia-reperfusion.

Prospective, randomized evaluation of midline fascial closure in gastric bariatric operations

BACKGROUND

Severe obesity is cited as a major risk factor for fascial wound dehisence and late incisional hernia after major abdominal surgery. The purpose of this study was to prospectively compare two methods of closure of the linea alba after gastric restrictive operations performed for treatment of morbid obesity.

METHODS

During a 6-year period 229 patients were randomized to have closure of the midline fascia using either a double-stranded #1 PDS suture placed in a continuous fashion or #1 Ethibond suture placed using an interrupted figure-eight technique.

RESULTS

Two of 109 patients who had closure with Ethibond suffered an acute dehiscence of the midline fascia vs no cases of fascial dehiscence in the PDS group. There were no wound infections in either group. There were 20 late incisional hernias (18%) in the Ethibond group vs 11 late hernias (10%) in the PDS group (P < or = 0.04). Mean postoperative follow-up time for all patients was 29.4 months. The cost of suture material and the time required to completely close the linea alba were also calculated for each group. The mean closure time in the Ethibond group was 13.3 vs 9.1 minutes in the PDS group (P < 0.0001). Although the cost per suture pack of #1 PDS was $4.63 vs $1.76 per pack for #1 Ethibond, the mean cost of sutures per patient was $4.81 for PDS vs $11.09 for Ethibond.

CONCLUSIONS

We conclude that #1 PDS placed in a continuous fashion provides a more secure and cost-effective closure of the midline fascia in morbidly obese patients than #1 Ethibond placed using an interrupted figure-eight technique.

Bacterial translocation after mesenteric ligation in dogs

These experiments were designed to determine the relationship between translocation of Escherichia coli and viability of ischemic small bowel. Twenty beagles were gavaged with 14C-labeled E. coli at two time intervals (3 and 24 h) prior to ligation of the blood supply to a 40-cm segment of ileum. Mesenteric lymph node (MLN) biopsies and bacterial cultures of the peritoneal fluid, peripheral arterial blood, and splanchnic venous blood were taken immediately prior to ligation and 24 h later both before and after the ischemic bowel was resected and anastomosed. Biopsies of each resection margin were taken to measure translocation of E. coli into the bowel wall. Several hemodynamic hemodynamic parameters were also measured before and 24 h after ligation. Seven of the 20 dogs died of further bowel necrosis. In survivors A-alpha DO2 was significantly decreased 24 h after mesenteric ligation vs. preligation, whereas in dogs that died DO2 was significantly increased after ligation vs. preligation. The incidence of mesenteric venous cultures positive for E. coli was significantly higher 24 h after ligation vs. preligation. However, there was no correlation between survival and the incidence of positive E. coli cultures in the blood or peritoneal fluid. Mean MLN counts were significantly higher in dogs gavaged at 3 h vs. those gavaged 24 h prior to laparotomy. However, there was no correlation between survival and translocation into either the bowel wall or MLN at either time interval. Viability of ischemic small bowel in this canine model was not affected by translocation of E. coli. Hemodynamic parameters that are altered during the course of sepsis also did not correlate with survival.

Update: NIH consensus conference. Gastrointestinal surgery for severe obesity

The 1991 Consensus Development Panel was instrumental both in establishing criteria for selection of patients for surgical treatment and in recognition of operations that have been shown to be safe and reasonably effective in the long term. The Panel may have been premature in endorsement of any form of banded gastroplasty because the long-term weight loss results of these procedures are frequently disappointing. It seems likely that a consensus panel on the same subject would be worthwhile in the next decade to carefully evaluate such procedures as biliopancreatic bypass and the various laparoscopic techniques for gastric banding. In 1996 surgery remains the only effective treatment for patients with medically severe (morbid) obesity.

A prospective, randomized trial of short versus long tubes in adhesive small-bowel obstruction

BACKGROUND

Many cases of acute adhesive small-bowel obstruction (SBO) can be successfully treated with intestinal tube decompression. There is considerable controversy, however, regarding whether a short nasogastric tube (NGT) or a long nasointestinal tube (LT) is the best method of intestinal tube decompression.

PATIENTS AND METHODS

A prospective, randomized trial was conducted to compare NGT and LT decompression with respect to the success of nonoperative treatment and morbidity of surgical intervention in 55 patients with acute adhesive SBO.

RESULTS

Twenty-eight patients were managed with NGT and 27 with LT. There were 44 cases of partial SBO (23 NGT, 21 LT) and 11 cases of complete SBO (5 NGT, 6 LT). Twenty-one patients ultimately required operation, including 13 managed with NGT (46%) and 8 with LT (30%) (P = 0.16). The mean period between admission and operation was 60 hours in the NGT group versus 65 hours in the LT group. At operation, 3 patients in the NGT group had ischemic bowel that required resection. Postoperative complications occurred in 23% of patients treated with NGT versus 38% of patients treated with LT (P = 0.89). Postoperative ileus averaged 6.1 days for NGT patients versus 4.6 days for LT patients (P = 0.44). There were no deaths.

CONCLUSIONS

Patients with adhesive SBO can safely be given a trial of tube decompression upon hospital admission. There was no advantage of one type of tube over the other in patients with adhesive SBO.

Interleukin-7 activates intestinal lymphocytes

Human intestinal lymphocytes, particularly intraepithelial lymphocytes, proliferate minimally to some agents, like mitogens and stimuli of the CD3 pathway. This in vitro finding may be due, in part, to a loss of factors found in vivo. Three T-cell growth factors, IL-7, IL-9, and IL-12, were tested for their ability to stimulate the proliferation of intestinal lymphocytes. Both intraepithelial lymphocytes and lamina propria lymphocytes proliferated more vigorously to IL-7 than to IL-9 or IL-12, and only IL-7 increased stimulation through the CD3 pathway. The IL-7-induced response was IL-2-dependent: IL-2 receptors appeared on both intestinal lymphocyte types, and antibody to the IL-2 receptor blocked IL-7-induced proliferation. Both CD4+ and CD8+ T-cell subsets responded to this cytokine as shown by phenotype-depletion experiments and constancy in the CD4/CD8 ratios after culture with IL-7. In addition, the T-cell receptor alpha beta and gamma delta subsets responded equally well to IL-7. This newly described selective proliferative response of intestinal lymphocytes to IL-7, but not to IL-9 or IL-12, requires no preactivation and may enhance growth in vivo.

The antiobstruction stitch in stapled Roux-en-Y enteroenterostomy

During the past 9 years, 393 Roux-en-Y gastric bypass operations for morbid obesity were performed by one surgeon at a university hospital. Twelve of the 393 patients subsequently developed mechanical small-bowel obstruction, and 7 of these 12 cases developed in the initial 38 patients in this series. There were 2 cases of small-bowel volvulus and 10 cases of postoperative adhesions. Three cases of adhesive obstruction occurred at the jejunojejunostomy. Two of the patients with anastomotic obstruction required operative treatment, whereas the remaining patient was successfully treated by nasogastric tube decompression. A simple technique is described that has successfully prevented this type of anastomotic obstruction in 355 subsequent Roux-en-Y gastric bypass operations. This technique should be useful in preventing anastomotic obstruction after any stapled end-to-side enteroenterostomy.

Comparison of blood flow and myoelectric measurements in two chronic models of mesenteric ligation

OBJECTIVE

To determine whether the predictive accuracy of intestinal motility and blood flow measurements is altered by the magnitude of ischemic damage.

DESIGN

Inception cohort study (dogs). Motility was measured using a probe that quantifies both the electromyographic (EMG) measurements and the magnitude of evoked contractile response (ECR). Intestinal blood flow was assessed using Doppler ultrasonography in the marginal artery and perfusion fluorometry, which quantifies fluorescein in the bowel wall in dye fluorescence units.

SETTING

Vivarium animal research facilities at a medical school.

INTERVENTIONS

The blood supply of a 40-cm length of ileum was ligated in 102 dogs: 52 in which the marginal artery was ligated at two points 8 cm apart (severe model), and 50 in which the marginal artery was ligated only once (moderate model). Twenty-four hours after ligation, the motility and blood flow parameters were measured in normal bowel and at 2-cm intervals within the 40-cm ischemic segment. Resection and anastomosis of ischemic bowel was then performed using either EMG, ECR, or fluorometry to determine the site of resection.

OUTCOME MEASURE

Anastomotic leak from progressive ischemia.

RESULTS

There were 26 fatal anastomotic leaks, all due to necrosis at the anastomosis. Perfusion fluorometry and ECR measurements did not correlate with survival in either model. An audible Doppler pulse in the marginal artery correlated with survival in the moderate (P < or = .02) but not the severe model (P = .59). The EMG measurements were significantly greater in survivors vs nonsurvivors in both models.

CONCLUSIONS

The EMG measurements may be useful in bowel viability assessment. Correlation of Doppler ultrasonographic findings with survival in the moderate model suggests that blood flow measurements may be more reliable in predicting viability in less ischemic bowel.

A multicenter, placebo-controlled, randomized, double-blind, prospective trial of prophylactic ursodiol for the prevention of gallstone formation following gastric-bypass-induced rapid weight loss

BACKGROUND

Previous studies have documented a high incidence of gallstone formation following gastric-bypass (GBP)-induced rapid weight loss in morbidly obese patients. This study was designed to determine if a 6-month regimen of prophylactic ursodiol might prevent the development of gallstones.

METHODS

A multicenter, randomized, double-blind, prospective trial evaluated 3 oral doses of ursodiol: 300, 600, and 1,200 mg versus placebo beginning within 10 days after surgery and continuing for 6 months or until gallstone development, for patients with a body mass index (BMI) > or = 40 kg/m2. All patients had normal intraoperative gallbladder sonography. Transabdominal sonography was obtained at 2, 4, and 6 months following surgery, or until gallstone formation.

RESULTS

Of 233 patients with at least one postoperative sonogram, 56 were randomized to placebo, 53 to 300 mg ursodiol, 61 to 600 mg ursodiol, and 63 to 1,200 mg ursodiol. Preoperative age, sex, race, weight, BMI, and postoperative weight loss were not significantly different between groups. Gallstone formation occurred at 6 months in 32%, 13%, 2%, and 6% of the patients on the respective doses. Gallstones were significantly (P < 0.001) less frequent with ursodiol 600 and 1,200 mg than with placebo.

CONCLUSION

A daily dose of 600 mg ursodiol is effective prophylaxis for gallstone formation following GBP-induced rapid weight loss.

Weight loss and dietary intake after vertical banded gastroplasty and Roux-en-Y gastric bypass

OBJECTIVE

The purpose of this study was to learn whether preoperative eating habits can be used to predict outcome after vertical banded gastroplasty (VBG) and Roux-en-Y gastric bypass (RYGB). BACKGROUND SUMMARY: Several independent randomized and sequential studies have reported significantly greater weight loss after RYGB in comparison with VBG. Although the mechanism responsible for weight loss after both procedures is restriction of intake rather than malabsorption, the relationships between calorie intake, food preferences, and postoperative weight loss are not well defined.

METHODS

During the past 5 years, 138 patients were prospectively selected for either VBG or RYGB, based on their preoperative eating habits. All patients were screened by a dietitian who determined total calorie intake and diet composition before recommending VBG or RYGB. Thirty patients were selected for VBG; the remaining 108 patients were classified as "sweets eaters" or "snackers" and had RYGB. Detailed recall diet histories also were performed at each postoperative visit.

RESULTS

Early morbidity rate was zero after VBG versus 3% after RYGB. There were no deaths. Mean follow-up was 39 +/- 11 months after VBG and 38 +/- 14 months after RYGB. Mean weight loss peaked at 74 +/- 23 lb at 12 months after VBG and 99 +/- 24 lb at 16 months after RYGB (p < or = 0.001). Twelve of 30 VBG patients lost > or = 50% of their excess weight versus 100 of 108 RYGB patients (p < or = 0.0001). Milk/ice cream intake was significantly greater postoperatively in patients who underwent VBG versus patients who underwent RYGB after 6 months (p < or = 0.003), whereas solid sweets intake was significantly greater after VBG during the first 18 months postoperatively (p < or = 0.004). Revision of VBG was performed in 6 of 30 patients (20%) for complications or poor weight loss, whereas only 2 of 108 patients who underwent RYGB required surgical revisions (p < or = 0.001).

CONCLUSIONS

These data show that VBG adversely alters postoperative eating behavior toward soft, high-calorie foods, resulting in problematic postoperative weight loss. Conversely, RYGB patients had significantly greater weight loss despite inferior preoperative eating habits. The high rate of surgical revision in conjunction with inconsistent postoperative weight loss has led us to no longer recommend VBG as treatment for morbid obesity.

The effect of gastric bypass surgery on hypertension in morbidly obese patients

BACKGROUND

Hypertension is the most common medical disorder associated with obesity. The relationship between dietary weight loss and the reduction of blood pressure is well established. However, the effect of gastric bypass surgery on blood pressure has not been well studied.

METHODS

We evaluated the relationship between weight loss and blood pressure in patients with diastolic hypertension who had gastric bypass surgery for morbid obesity. Patients were defined as hypertensive if taking antihypertensive medication or if both the preoperative office and mean hospital diastolic blood pressures were greater than 90 mmHg. Two of the authors (J.L.C., M.E.R.), blinded to all postoperative weights, classified the follow-up hypertensive status into one of four categories: resolved, improved, no change, or worse. The relationship between postoperative changes in blood pressure status and mean weight loss, percent excess weight loss, and body mass index were examined using a one-way analysis of variance. The relationship between postoperative weight loss and blood pressure was assessed in the baseline normotensive population using linear regression analysis.

RESULTS

There were 45 patients with diastolic hypertension; 91% were taking an antihypertensive medication. The mean follow-up was 39 months. The mean preoperative weight was 137 kg and the mean weight loss at 1, 12, and 24 months following surgery was 13, 21, and 45 kg, respectively. Twelve months after surgery, hypertension had resolved in 22 patients (54%) and had improved in six patients (15%). These findings persisted through 48 months postoperatively. There was a significant relationship between the percentage of excess weight lost and improvement of hypertension at the 6-month and 12-month follow-up visits. There was also a significant relationship between the body mass index and improvement of hypertension at the 1-month, 12-month, 24-month, and 48-month follow-up visits. In the baseline normotensive patients there was not a significant relationship between our weight loss measures and changes in blood pressure.

CONCLUSIONS

We conclude that postoperative weight loss in patients undergoing gastric bypass surgery was associated with resolution or improvement of diastolic hypertension in approximately 70% of cases. Resolution or improvement of hypertension occurred more often in patients with a lower postoperative body mass index.

Determination of small bowel viability using quantitative myoelectric and color analysis

Intraoperative assessment of viability in ischemic bowel remains a major unsolved problem in general surgery. Bowel viability was assessed in 31 dogs 24 hr after mesenteric arterial ligation in a 40-cm segment of ileum. The purpose of this study was to evaluate two new quantitative methods of viability assessment, electromyography (EMG) and reflection densitometry. These methods were compared with traditional methods of bowel viability assessment. EMG was measured using a specially designed probe which contains an electronic control unit for computer-assisted data acquisition. A computer algorithm quantified the EMG. Reflection densitometry quantified bowel color in the red and blue spectrum. Presence of visible peristalsis, Doppler ultrasound, and a visual color grading system were also used in viability assessment. Each parameter was measured at 2-cm intervals along the ischemic segment. Resection and anastomosis of ischemic bowel were then performed. There were nine deaths from anastomotic leak, all resulting from further bowel necrosis. EMG was the only viability assessment parameter that correlated with survival. EMG at the resection margin in survivors was 29 +/- 3% vs 23 +/- 4% at the resection site of nonsurvivors (P < or = 0.047 by unpaired Students t test). These results suggest that quantitative EMG measurements may be useful in assessment of viability in ischemic bowel.

Spontaneous cytotoxicity of intestinal intraepithelial lymphocytes: clues to the mechanism

Human intestinal intraepithelial lymphocytes (IEL) demonstrate target cell-restricted spontaneous cytotoxic (SC) activity that is due to CD2+CD3+CD8+CD16-CD56- effector cells; they kill epithelial cell (EC) tumours (such as DLD-1 colon cancer cells), but not natural killer (NK)-sensitive K-562 cells. The present study shows that the measured levels of SC activities by IEL correlated with those of autologous lamina propria lymphocytes (LPL), but not with those of peripheral blood lymphocytes (PBL). Also, the susceptibilities of DLD-1 cell clones to lysis by IEL and PBL effector cells did not correlate, suggesting different mechanisms of lysis. Antibody blocking experiments showed that the main surface molecules involved in lysis depended on the effector cell type: alpha E beta 7 (HML-1) on IEL and CD16 on PBL. No antibody-dependent cell-mediated cytotoxicity (ADCC) was demonstrated by IEL, even after stimulation with interferon-gamma (IFN-gamma). Few IEL expressed Fc receptors for IgG. This study describes further differences between the SC activities of IEL and PBL.

Lipoprotein lipase regulation by insulin and glucocorticoid in subcutaneous and omental adipose tissues of obese women and men

There are marked variations in the activity of lipoprotein lipase (LPL) among adipose depots, particularly in women. Consistent with data on LPL activity, the level of expression of LPL mRNA was lower in omental (OM) than subcutaneous (SQ) adipose tissue of women. To investigate the cellular basis of these differences, OM and SQ adipose tissues obtained at surgery from obese men and women were placed in organ culture for 7 d with varying concentrations of insulin and dexamethasone. Insulin increased levels of LPL mRNA and LPL activity in abdominal SQ but not OM adipose tissue. Dexamethasone also increased LPL mRNA and LPL activity, and these effects were more marked in the OM adipose tissue, particularly in men. When insulin and dexamethasone were added together, synergistic increases in LPL activity were seen in both depots, and this was in part explained at the level of LPL mRNA. The SQ depot was more sensitive to the effects of submaximal doses of dexamethasone in the presence of insulin. The maximum activity of LPL induced by insulin or insulin plus dexamethasone was higher in the SQ than in the OM depot of women, and this was associated with higher levels of LPL mRNA. Rates of LPL synthesis paralleled LPL mRNA levels. These data show that insulin and glucocorticoids influence human adipose tissue LPL activity at the level of LPL gene expression, as well as posttranslationally, and that responsiveness to these hormonal effects is dependent on adipose depot and gender.

Elective one-stage abdominal operations after percutaneous catheter drainage of pyogenic liver abscess

During the past 10 years, 15 patients have had percutaneous catheter drainage (PCD) of pyogenic liver abscesses (PLA) at a major teaching hospital. Five PLA were related to biliary tract disease, two were secondary to colonic diverticulitis, two developed after abdominal surgery, and the remaining were associated with hepatic trauma, gastric ulcer, Crohn's ileitis, and colon cancer. Two abscesses were cryptogenic. Mean diameter of PLA was 8 cm and ranged from 2-14 cm. Three patients had multiple PLA. All patients were initially treated by PCD without major complications. However, one patient required a second PCD after developing a recurrent abscess. Fever and leukocytosis defervesced at a mean 3.6 days and 7 days, respectively, after PCD. Seven of the 15 patients subsequently had one-stage elective abdominal operations for treatment of diseases underlying PLA including two cholecystectomies, two colon resections, one gastrectomy, one ileostomy closure, and one laparotomy for unresectable gall bladder cancer. There were no postoperative complications. These results demonstrate that PLA are best treated by using PCD as primary treatment with surgical drainage reserved for patients who do not respond clinically to PCD. The need for operative treatment in diseases underlying PLA should not deter use of PCD as primary treatment.

Operative tube versus percutaneous cholecystostomy for acute cholecystitis

The records of 26 patients who underwent cholecystostomy procedures for presumed acute cholecystitis during a 6-year period were reviewed. Nine patients had operative tube cholecystostomy (OC), and 17 patients had radiologic percutaneous cholecystostomy (PC). A correct diagnosis of acute cholecystitis was made in 22 of 26 patients (84%), including 14 of 17 PC patients and 8 of 9 in the OC group. The rate of resolution of cholecystitis was the same in each group (75% OC versus 78% PC). APACHE II scores prior to treatment were significantly higher in OC patients (20.9 OC versus 12.4 PC, p < 0.01). There were 5 deaths, including 3 in the OC groups and 2 in the PC group. Nonfatal complications were more frequent in the PC group. Two of the 14 correctly diagnosed PC patients (14%) subsequently required emergency cholecystectomy for persistent biliary sepsis, and 6 patients (43%) required at least 1 tube exchange for occlusion or dislodgement. Overall, only 5 of the 14 patients (36%) in the PC group were successfully treated without complications compared with 5 of 8 patients (63%) in the OC group. Despite its theoretical advantages, PC was no more effective than OC in the treatment of acute cholecystitis. These data suggest that OC remains a viable treatment option in critically ill patients with acute cholecystitis.

Healing of the stapled stomach in bariatric operations

Breakdown of the in-continuity gastric staple line after gastroplasty and gastric bypass is frequently associated with either complications or unsatisfactory weight loss. Although there is wide variation in the reported incidence of stale-line disruption after gastric bariatric operations, this complication is most frequently recognized by surgeons who routinely examine the integrity of the staple line at 12 months or more after operation. Upper gastrointestinal contrast studies are more sensitive than upper endoscopy in detecting small defects in the stapled gastric partition. The stomach should be routinely divided in patients who require reoperation for late staple-line disruption. This complication could be prevented by routine transection of the stomach at the initial gastric restrictive operation.

Intraoperative assessment of bowel viability

Viability of ischemic bowel was assessed in 30 dogs after mesenteric arterial ligation in a 40-cm length of ileum. Viability was evaluated using two gross features, color and peristalsis, and four objective methods including bowel wall surface oximetry (pO2), Doppler ultrasound, quantitative fluorescein fluorimetry, and myoelectric activity measured by a strain gauge probe. Each parameter was measured at 2-cm intervals within the 40-cm ischemic segment before resection and anastomosis was performed. There were seven fatal anastomotic leaks, all due to further bowel necrosis. Survival did not correlate with bowel color, presence of peristalsis, bowel wall pO2 Doppler ultrasound, or the myoelectric parameters. However, fluorescein fluorimetry was predictive of long-term viability. These results suggest that quantitative fluorescein fluorimetry may be a useful adjunct in intraoperative bowel viability assessment.

Long-limb gastric bypass in the superobese. A prospective randomized study

This study was designed to determine whether greater diversion of bile and pancreatic secretions away from the functional gastrointestinal tract would produce greater weight loss in superobese patients (greater than or equal to 200 pounds overweight) in comparison with conventional Roux-en-Y gastric bypass (RYGB). During the past 7 years, two modifications of RYGB were prospectively compared in 45 superobese patients: RYGB-1, in which the length of defunctionalized jejunum measured 75 cm, and RYGB-2, in which the defunctionalized jejunum measured 150 cm. Respective mean preoperative weight/body mass indexes were 393 pounds/63.4 for 22 RYGB-1 patients and 404 pounds/61.6 for 23 RYGB-2 patients. Two patients (5%) had nonfatal early complications. There were six late incisional hernias. There were no cases of protein deficiency, hepatic dysfunction, or diarrhea after operation. Mean follow-up was 43 +/- 17 months. Postoperative weight loss in pounds and daily calorie intake were compared at 6-month intervals. Weight loss stabilized by 24 months at a mean 50% excess weight lost in RYGB-1 patients and 64% excess weight lost in RYGB-2 patients. Nineteen of 23 RYGB-2 patients achieved at least 50% excess weight lost versus 11 of 22 RYGB-1 patients (p less than or equal to 0.03). Weight loss was significantly greater at 24 through 36 months in RYGB-2 versus RYGB-1 patients (p less than 0.02). There was no significant difference in either calorie intake or incidence of iron and vitamin B-12 deficiency between the two groups. These data show that gastric restriction and biliopancreatic diversion without intestinal exclusion resulted in significantly greater weight loss than conventional RYGB but did not cause additional metabolic sequelae or diarrhea. This long-limb modification of Roux-en-Y gastric bypass is a safe and effective procedure in patients who are 200 pounds or more overweight.

Critical analysis of results: weight loss and quality of data

Difficulties associated with outcome assessment of operations performed for treatment of morbid obesity include lack of uniform standards for reporting results, failure to account for the response of related medical problems to weight loss, and lack of actuarial data for patients greater than or equal to 45 kg overweight. The purpose of this report is to critically analyze various methods of outcome assessment including the 5-y postoperative weight loss results of vertical banded gastroplasty and Roux-en-Y gastric bypass. Weight loss after these procedures usually reaches a nadir between 18 and 24 mo postoperatively. Mean percent excess weight loss at greater than or equal to 5 y ranged from 48% to 74% after gastric bypass and from 50% to 60% after vertical banded gastroplasty. Medical problems are almost invariably improved with satisfactory weight loss. Surgery remains the mainstay in treatment of morbid obesity because of the nearly 100% failure rate of nonoperative treatment in these patients.

Multivitamin prophylaxis in prevention of post-gastric bypass vitamin and mineral deficiencies

One hundred forty patients were followed for a mean 24.2 months after gastric bypass. Postop multivitamin (MV) prophylaxis was recommended for all patients and 90 of 140 patients (64 percent) were regularly compliant. Deficiencies in iron, vitamin B-12 or folate were recognized in 88 of 140 patients (63 percent). Thirty of 45 patients (67 percent) with iron deficiency developed anemia. Forty-three of the 52 patients who did not have deficiencies were regularly taking MV vs 47 of 88 patients who developed deficiencies (P less than 0.001). MV prophylaxis was successful in preventing folate (P less than or equal to 0.05) and vitamin B-12 deficiencies (P less than or equal to 0.02) but did not prevent development of iron deficiency or subsequent anemia. There was no correlation between taking prescribed supplements and resolution of either iron deficiency of anemia. B-12 and folate supplements corrected deficiencies in 73 percent of cases. We conclude that oral MV prophylaxis is useful in preventing folate and B-12 deficiency after gastric bypass. Additional prophylactic iron supplements should be provided for women to prevent iron deficiency and associated anemia.

Limitations of percutaneous catheter drainage of abdominal abscesses

During the past eight years, 119 patients with abdominal abscesses underwent percutaneous catheter drainage (PCD), including 76 who had successful treatment by the initial PCD, 19 who had recurrent abscesses after removal of drainage catheters and 24 who were outright failures and either died of sepsis or required surgical drainage. This study was designed to identify outcome variables that might be used prospectively to assess the therapeutic efficacy of PCD. Outcome variables included abscess size, daily drainage volume and location, presence of a gastrointestinal fistula, age, bacteriologic factors and response of the pulse rate, body temperature and leukocyte count of the patient to PCD. Ninety of 119 patients (76 per cent) ultimately had successful drainage of abscesses by PCD alone. The over-all mortality rate was 16 per cent (19 of 119), with a 75 per cent mortality rate in the failure group. Neither abscess size, bacteriologic findings nor pulse rate correlated with outcome. PCD failure was significantly greater in patients greater than or equal to 60 years (p less than or equal to 0.01) and in patients with pancreatic abscesses versus other locations (p less than or equal to 0.04). Drainage volume was significantly greater in PCD failures than among PCD successes at greater than or equal to 3 days after PCD (p less than or equal to 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)

Human intraepithelial lymphocytes. Immunomodulation and receptor binding of vasoactive intestinal peptide

This study evaluates the immunomodulation and receptor binding of vasoactive intestinal peptide on human peripheral blood lymphocytes and intraepithelial lymphocytes. Vasoactive intestinal peptide (VIP, 10(-8) and 10(-12) M) had no effect on the concanavalin A-induced proliferation or the spontaneous cytotoxicity against K-562 targets by either lymphocyte type. Human peripheral blood lymphocytes had a mean of 927 vasoactive intestinal peptide receptors per cell with a Kd of 1.12 x 10(-10) M, as demonstrated by the competitive displacement of [125I]peptide by unlabeled peptide using Scatchard analysis. In contrast, intraepithelial lymphocytes had no high-affinity receptors as shown by the negligible binding of 50 pM [125I]VIP. Peptide binding by peripheral blood lymphocytes, although reduced by exposure to dithiothreitol and ethylenediamine tetraacetic acid, was still greater than binding by intraepithelial lymphocytes. As intraepithelial lymphocytes are mainly CD8+ T cells, the possibility that this phenotype may not bind VIP at all was tested by specifically depleting peripheral blood lymphocytes by antibody and complement lysis. Peripheral blood lymphocytes expressing CD8, CD4, and/or CD2 were responsible for most of the binding, indicating that CD8+ T lymphocytes in the peripheral blood and in the intestinal epithelium differ in their capacity to bind VIP.

Use of nutrition support in patients with AIDS: a four-year retrospective review

A series of 55 patients with AIDS and opportunistic infections were admitted a total of 75 times to Robert Wood Johnson University Hospital over a 4-year period, and supplemental nutrition support--intravenous (IV), enteral, or both--was given during 32 of these admissions. Use of nutrition support was correlated retrospectively with pretreatment nutritional status, length of hospital stay (LOS), and survival and was found to be positively correlated with weight loss greater than or equal to 10% or weight less than or equal to 90% of ideal body weight (p less than 0.001), admission hemoglobin less than or equal to 10g (p less than 0.001), and LOS less than or equal to 21 days (p less than or equal to 0.003). Nutrition support intervention did not correlate with survival, admission total lymphocyte count (TLC), or serum albumin level. Survival was negatively correlated with LOS (p less than or equal to 0.04) and continuous daily fever for greater than or equal to 6 days (p less than 0.001). Survival was also significantly lower in patients who received IV rather than enteral nutrition support (p less than or equal to 0.03). Weight loss, admission TLC, albumin, and hemoglobin levels did not correlate with survival. These results suggest that nutrition support generally was given to the sickest patients with AIDS. There was no measurable benefit associated with use of supplemental nutritional support in this series. Properly designed trials will be necessary to define the optimum route, timing, and type of nutritional support for patients with AIDS.

Serum lipids after gastric bypass surgery for morbid obesity

Thirty-eight of 151 consecutive patients (25 percent) undergoing bypass surgery for morbid obesity had increased serum levels of total cholesterol (TC), triglycerides (TG) or both preoperatively. Ten patients had isolated TC elevation, six had isolated TG elevation and 22 had both TC and TG elevation. High density lipoprotein-cholesterol (HDL-C) levels were subnormal in 28 of the 38 patients (74 percent). Fasting lipid profiles were determined in the 38 hyperlipidemic patients at 6-month intervals postoperatively. Mean follow-up period was 29 months. By 6 months postop, patients had a greater than or equal to 20 percent mean reduction in TC and greater than or equal to 50 percent mean reduction in TG which were significant in comparison with preop levels and correlated with weight loss (P less than or equal to 0.05). Mean HDL-C levels had increased significantly vs. preop levels by 12 months postop (P less than 0.05). Lipid profiles became normal in 32 of the 38 patients (84 percent). Improvements in lipid profile were sustained in all patients with satisfactory weight loss but regressed after 12 months in patients who did not lose greater than or equal to 50 percent of their excess weight. These results suggest that abnormal serum lipid profiles can be permanently improved with sustained weight loss after gastric restriction surgery for morbid obesity.