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81.
Background: The cottage cheese test was developed in an attempt to find a simple way to measure functional pouch volume and to better understand the fate of the tiny proximal pouch following the gastric bypass procedure. Methods: Our patients were asked to eat cottage cheese in a structured fashion before their return visits from 3 months to 2 years postoperatively. Results: We found there was a step-wise progression of increase in functional pouch volume with statistical significance between each time interval. Also, we compared the patients' excess weight loss at 1, 2, and 3 years postoperatively to their pouch size at 1 year postoperatively. Although there is a wide range (2.5-9.0 oz) of pouch sizes at 1 year, there is no significant difference in excess weight loss between the smaller and larger pouches. Conclusions: The pouches enlarge by the orderly process of hyperplasia. Within the 2.5-9 oz volume variation, the pouch volume alone is not a predictor of weight loss. Rather, how the patient uses the pouch/tool, in addition to the other behavior modifications, determines the degree of weight loss. This data strongly suggests that the surgeon's understanding of and teaching of the optimal use of the pouch/tool may be more important than previously thought.  相似文献   
82.
Background: The pharmacokinetic variables of drug clearance and volume of distribution are usually corrected for body weight or surface area. Only recently have the relationships which exist between body size, physiologic function and pharmacokinetic variables been evaluated in the obese population. These effects are not widely known, and data on this and the effects of bariatric surgical procedures are scantily documented in the surgical literature. Methods: Literature review. Results: Drugs with a low or moderate affinity for adipose tissue have a moderate increase in the volume of distribution (Vd), and this correlates with the increase in lean body mass (LBM). Highly lipophilic drugs, with some exceptions, show the expected increase in Vd and prolongation of elimination half-life, indicating a marked distribution into adipose tissue. Drug absorption, in general, is slowed by delayed gastric emptying and is normal when gastric emptying is normal or increased. Most drug absorption occurs in the small intestine where duration of drug/mucosal contact is the most important factor. Conclusions: Drugs whose distribution is restricted to LBM should utilize a loading dose based on ideal body weight (IBW). For those drugs which distribute freely into adipose tissue, the loading dose should be based on total body weight (TBW). Adjustment of the maintenance dose depends on clearance rates. In a few cases dosage adjustment depends on pharmacodynamic data, since drug clearance does not conform to these recommendations, for reasons which remain to be defined. Following bariatric surgery, in the absence of delayed gastric emptying or uncontrolled diarrhea, drug absorption rates are usually comparable to the non-operated patient.  相似文献   
83.
Mason EE 《Obesity surgery》1996,6(3):218-223
BACKGROUND: Have surgeons in North America accepted operations for the treatment of severe obesity? This question was posed by organizers of the Ninth International Symposium on Obesity Surgery that met in Stockholm in September, 1995. Study design: In order to obtain opinions which might help to answer the question posed, a 1-page questionnaire was sent to 151 chairmen of academic departments of surgery in North America in December 1994 asking about the acceptance and use of surgical operations for the treatment of severe obesity. RESULTS: Answers, received from 112 or 74%, indicated that operative treatment should be used (74%), was effective (77%) and safe (71 %). However, only 65% of departments provided such operations. Operative treatment for obesity was available outside the department in 53%. The operations most frequently used were Roux-en-Y gastric bypass (RGB) and vertical banded gastroplasty (VBG). A single operation was offered by 44 departments and a choice of two or more operations in 30 departments. RGB and VBG were equally in use. Gastric banding was used as an alternative to VBG in six departments. Other operations were in use in six departments either alone (three) or as alternatives to RGB and VBG (three). CONCLUSIONS: It appears that surgical treatment of obesity is accepted and available in the majority of academic departments of surgery.  相似文献   
84.
The Gastric Bypass for Failed Bariatric Surgical Procedures   总被引:1,自引:0,他引:1  
Fox SR  Fox KS  Oh KH 《Obesity surgery》1996,6(2):145-150
Background: Revision of failed bariatric surgical procedures is a significant challenge for every bariatric surgeon. Methods: Evaluated are surgical difficulties, management problems and weight loss in patients with distal gastric bypass as a revisionary procedure. Eighty patients were followed up to 3 years; four were lost to follow-up. Mean age was 43; mean prebariatric surgery weight 134 kg; height 1.65 meters; body mass index 40.1; ideal body weight 62.7 kg; excess weight 70.5 kg; per cent excess weight 214%. A 250 cm stomach-to-ileocecal valve segment of small bowel was used, and the biopancreatic secretions were brought into the terminal ileum 100 cm from the ileocecal valve. Mean pouch size was 63 cc; length of hospital stay 5 days; operative blood loss 616 cc; operative time 130 min. Results: Intraoperative complications included three splenic injuries (without splenectomy). Early complications included one deep vein thrombosis, two marginal ulcers, one GI hemorrhage, one wound dehiscence, one pouch outlet obstruction and one pancreatitis. Late complications included: one death from protein malnutrition/ARDS; 21 hypoproteinemia; six protein malnutrition, and of these, three had hyperalimentation; three cholecystitis; 27 anemia; 22 incisional hernia; two staple-line disruption (reoperated); 26 low serum iron; 11 prolonged (> 6 months) diarrhea; three prolonged frequent vomiting; and two unrelated deaths (chronic myelogenous leukemia and amyotrophic lateral sclerosis). Mean excess weight loss was 83% at 12 months; 89% at 24 months; and 94% at 36 months. Conclusion: The distal gastric bypass is fraught with the operative and immediate post-operative complications experienced in any revisionary bariatric surgery. Distal gastric bypass is very effective in producing long-term weight loss. Nutritional problems are common but usually easily corrected. The most serious nutritional complication is protein malnutrition, which must be identified and corrected early. Success of this procedure is dependent upon patient compliance with proper nutrition and supplements, and regular office follow-up with monitoring of laboratory data. Patients who are noncompliant are at significant risk for complications.  相似文献   
85.
Summary The effects of cocaine on the contractile response of isolated human nasal mucosal blood vessels to field stimulation and methoxamine were investigated. Results showed that cocaine antagonized methoxamine and inhibited field stimulation. The drug increased resting tension in human nasal mucosa in vitro through direct actions and potentiated mucosal contractions by norepinephrine and epinephrine. The study indicated that high concentrations of cocaine may actually antagonize -adrenoceptors, but these concentrations are not necessary in eliciting desired degrees of vasoconstriction in nasal blood vessels while being applied as a local anesthetic.  相似文献   
86.
Transepithelial pathways of macromolecule transport have been studied in vitro in rabbit nasal respiratory mucosa, maintained at 27° C. Transepithelial electrical potential difference, short-circuit current and resistance were 3.4±0.5mV (submucosa positive), 65.0±6.7 A cm–2 and 52.1±5.6 cm–2 respectively (n=15). These electrical characteristics are those of a leaky epithelium allowing macromolecules to permeate paracellularly. A detailed permeation study of a polypeptide (elcatonin, M w=3362) was also undertaken. Elcatonin mucosa-submucosa (J ms) and submucosa-mucosa (J sm) fluxes were measured by radioimmunoassay. With 10 g/ml elcatonin, J ms was significantly larger than J sm for the whole 120-min period of observation; net flux showed a maximum in the first 30 min (J ms=13.6±1.0 ng cm–2 h–1, J sm=1.4±0.1 ng cm–2 h–1, n=10). J ms fell towards the value of J sm if the temperature was reduced to 4°C or if the mucosa was simultaneously treated with 0.1 mM dinitrophenol and 3 mM monoiodoacetate. J ms and J net followed saturation kinetics with increasing elcatonin concentrations. Adrenocorticotropic hormone (M r=4500) produced a similar pattern to elcatonin. However, J ms and J sm were not significantly different from each other at any time either for [3H]sucrose (M w=342) or for [14C]polyethyleneglycol-4000 (M w=4000) when present in the bathing medium at 500 M concentration. The results show active transport of polypeptides in parallel with passive permeation (possibly through leaky intercellular junctions). Active transport does not appear to be related to nonspecific pinocytosis but to receptor-mediated endocytosis. The latter may be important for the sampling of potential antigens from the nasal lumen.  相似文献   
87.
From a total material of 184 Swedish users of loose packed moist snuff and 68 users of portion-bag packed moist snuff, cases were selected from subgroups based on a four-point clinical grading scale. The selected material for the study comprised 70 cases (ten from each clinical grade group, no Degree 4 lesion was found among portion-bag users). Features recognized in biopsies from these cases together with findings in previous studies correlated well with the use of a four-point scale for the grading of clinical changes, especially in the context of discriminating lesions for which special efforts should be undertaken to make the patient stop or change the snuff dipping habit and for selecting patients in whom regular clinical follow-up including a biopsy should be carried out. In this article is also discussed the labeling of the clinical oral mucosal changes seen at the site where a quid of snuff is regularly placed. The conceptual use of "snuff dippers' lesions" is recommended instead of e.g. snuff-induced leukoplakia.  相似文献   
88.
The fascia banded stoma Roux-en-Y gastric bypass (RYGBP) has been effective both as a primary and revision operation for severe obesity or failure of another operation. Since May 1984, 361 primary and 100 revisional fascia banded RYGBP operations have been reported. Weight loss achieved a mean body mass index of 30 for primary and 31 for revision patients at most recent follow-up of 3-6 years (mean 4.3 years) postoperatively. Mean overweight was 28% for primary, and 34% for revision patients. Eighty percent of primary and 79% of revision patients were within 50% of ideal weight. Revision rates for these patients were 0 for primary and 1% for revision patients. Operative mortality was 0 for primary and 1% for revision patients. Since morbidity and mortality, although low, are higher for revision than primary surgery, it is important to use an effective primary operation.  相似文献   
89.
A review of 150 charts revealed that 36 patients had pre-operative serum cholesterol greater than 200 mg% prior to Roux-Y gastric bypass. The average pre-operative weight was 266 lb (121 kg) and at 1 year post-operative 166 lb (75 kg), or 100 lb (45 kg) lost (77% excess weight loss). We compared the following pre- and post- operative data and found that: (1) cholesterol was decreased by 24% and triglycerides decreased by 40%; (2) post-operative cholesterol/HDL-C ratio of 3.31 put our patients in the half of average risk category for a clinical pathological coronary event according to the SmithKline Beecham Laboratories risk ratio chart. We conclude that Roux-Y gastric bypass and its ability to produce a significant weight loss and markedly affect cholesterol and triglyceride metabolism will also reduce a patient's risk of myocardial infarction.  相似文献   
90.
Many forms of gastric banding have been described and high reoperation rates reported. These can be mainly attributed to excess vomiting associated both with and without stenosis. Reflux oesophagitis and the ‘sump’ effect may be other causes. This paper examines the problems associated with banding leading to revisional surgery and introduces a new technique, ‘fundal supporting suture’, to correct these problems. Preliminary results on 126 bandings without the modification and 22 with the modification are presented.  相似文献   
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