Does establishing a bariatric surgery fellowship training program influence operative outcomes?

BACKGROUND: Roux-en-Y gastric bypass (RYGB) has a long learning curve that may be reflected in operative outcomes. This study sought to assess whether training a fellow has an impact on the operative outcomes of the training program. METHODS: Prospectively collected data on 150 consecutive patients were compared before (group 1) and after (group 2) establishment of a fellowship-training program. RESULTS: A greater number of patients underwent laparoscopic RYGB (LRYGB) in group 2 than in group 1 (63% vs 46%; p = 0.01). The group 2 patients were similar to the group 1 patients in terms of age, gender, length of stay, and complication rate. However, they had a higher body mass index (BMI) (median 50 kg/m2; range, 39-64 kg/m2 vs median, 46 kg/m2; range, 38-56 kg/m2; p = 0.01) and a higher incidence of prior abdominal procedures (21% vs 7%; p = 0.006). In addition, operative time was significantly shorter for the patients who underwent open RYGB (ORYGB) (median, 150 min; range, 65-280 min vs median, 110 min; range, 50-210 min; p < 0.001) and LRYGB (median, 202 min; range, 105-450 min vs median, 134 min; range, 50-191 min; p < 0.001) in group 2 than for the patients in group 1. The patients who underwent ORYGB in groups 1 and 2 had similar characteristics and outcomes. Increasing experience with both ORYGB and LRYGB correlated with a decrease in operative times for group 2 (p < 0.001), but not for group 1. CONCLUSION: Establishment of a fellowship program shortens the operative times for both open and laparoscopic RYGB and expands the scope of bariatric practice by compounding the experience of the operating team without increasing complications.

Does experience preclude leaks in laparoscopic gastric bypass?

BACKGROUND: Improved outcomes of laparoscopic Roux-en-Y gastric bypass (LRYGB) have been demonstrated once pratice has moved beyond the learning curve. However, there is no evidence that experience has a favorable impact on the incidence of leaks. This study evaluated the incidence of staple-line leaks as experience accrued in a university-based bariatric surgery program. METHODS: Prospectively collected data on our first 200 patients undergoing LRYGB since July 1998 were analyzed. Linear staplers were used to divide the stomach and to create a side-to-side jejunojejunostomy. A side-to-side cardiojejunostomy was created using a 21-mm circular stapler. Patient characteristics, operative data, and outcomes were evaluated chronologically with comparison of outcomes between quartiles. RESULTS: Staple-line leaks developed in 9 (4.5%) of the first 200 patients undergoing LRYGB. Among the 200 patients were 190 women (95%). The median age of the patients was 48 years (ranges, 24-62 years), and their body mass index was 43 kg/m(2) (ranges, 32-59 kg/m(2)). As surgeons' experience increased over time, there was a significant increase in the weight of patients and the percentage of patients with previous abdominal operations. There also was a significant decrease in conversion rates and operative times. Leaks occurred in six patients at the cardiojejunostomy (3%), in two patients jejunojejunostomy (1%), and in one patient at the excluded stomach (0.5%). Of the 50 leaks that occurred in each quartile, there were in the 3 in the 1st quartile, 1 in the 2nd quartile, 2 in the 3rd quartile, 3 in the 4th quartile. The differences were not significant. There was no correlation between the number of LRYGBs, and the occurrence of a leak (p = 0.59 confidence interval -0.13-0.22). CONCLUSIONS: The incidence of staple-line leaks appears to be independent of the number of LRYGBs performed. These data suggest that surgeons' experience may not eliminate anastomotic complications experienced by patients undergoing LRYGB.

Location, not staging, of cholangiocarcinoma determines the role for adjuvant chemoradiation therapy.

The role of adjuvant chemoradiation therapy (CT/XRT) in the treatment of cholangiocarcinoma is controversial. We undertook this study to determine whether CT/XRT is appropriate after resection of cholangiocarcinomas. One hundred ninety-two patients with cholangiocarcinomas were treated from 1988 to 1999. After resection, patients were assigned a stage (TNM) and were stratified by location of the tumor as intrahepatic, perihilar, and distal tumors. Data are presented as mean +/- standard deviation. Of 192 patients 92 (48%) underwent resections of cholangiocarcinomas. Thirty-four patients had liver resections, 25 had bile duct resections, and 33 underwent pancreaticoduodenectomies. Thirty-four patients had adjuvant CT/XRT, three had adjuvant chemotherapy, four had neoadjuvant CT/XRT, and 50 had no radiation or chemotherapy. Mean survival of resected patients with adjuvant CT/XRT was 42 +/- 37.0 months and without CT/XRT it was 29 24.5 months (P = 0.07). Mean survival of patients with distal tumors receiving or not receiving CT/XRT was 41 +/- 21.8 versus 25 +/- 20.1 months, respectively, (P = 0.04). Adjuvant chemoradiation improves survival after resection for cholangiocarcinoma (P = 0.07) particularly in patients undergoing resection for distal tumors (P = 0.04). Benefits of adjuvant CT/XRT are apparent when stratified by location of cholangiocarcinomas rather than staging.

Delay in treatment of biliary disease during pregnancy increases morbidity and can be avoided with safe laparoscopic cholecystectomy.

Recent reports indicate that laparoscopic cholecystectomy in pregnancy is safe. The aim of this study was to evaluate whether delays in definitive treatment of symptomatic cholelithiasis increase morbidity. We reviewed the records of 16 women who underwent laparoscopic cholecystectomy during pregnancy between 1992 and 1999. Mean age was 24 +/- 5 years (mean +/- standard error). Symptom onset was during the first trimester in nine patients, second trimester in six patients, and third trimester in one patient. Patients had abdominal pain (93%), nausea (93%), emesis (80%), and fever (66%) for a median of 45 days (range 1-195 days) before cholecystectomy. Nine of 11 women who underwent cholecystectomy more than 5 weeks after onset of symptoms experienced recurrent attacks necessitating 15 hospital admissions and four emergency room visits. Moreover four women who developed symptoms in the first and second trimesters but whose operations were delayed to the third trimester had 11 hospital admissions and four emergency room visits; three of those four (75%) women developed premature contractions necessitating tocolytics. Cholecystectomy was completed laparoscopically in 14 women. There was no hospital infant or maternal mortality or morbidity. We recommend prompt laparoscopic cholecystectomy in pregnant women with symptomatic biliary disease because it is safe and it reduces hospital admissions and frequency of premature labor.

Clinical predictors of sleep apnea in patients undergoing bariatric surgery.

BACKGROUND: Sleep apnea is a frequent and unappreciated condition of morbidly obese patients. If unrecognized it could lead to significant postoperative complications. A clinical tool to assess the severity of sleep apnea is not available. We prospectively determined whether the Epworth Sleepiness Scale (ESS) or body mass index (BMI) predict the severity of sleep apnea in morbidly obese patients. METHODS: 66 consecutive patients evaluated for bariatric surgery from June to November 1999 were examined and prospectively administered a health questionnaire including the ESS. Patients with an ESS > or =6 were referred for polysomnography with calculation of Respiratory Disturbance Index (RDI). Sleep apnea was graded as mild (RDI 6-20), moderate (RDI 21-40) and severe (RDI>40). Clinical variables such as BMI and ESS score were compared using regression analysis. Data are mean +/- SEM. RESULTS: 4 men and 23 women (27/66) who scored >6 on the ESS completed a sleep study. Mean ESS was 13+/-4.5. Sleep apnea was mild in 13 patients, moderate in 7, severe in 6, and absent in 1. Mean age was 43+/-9.5 years. BMI was 52+/-10 kg/m2. Linear regression analysis did not demonstrate correlation between ESS score and severity of sleep apnea (r2=0.03, p>0.05). Multiple regression analysis demonstrated no correlation between BMI, patient snoring, and RDI score. CONCLUSIONS: Sleep apnea is frequent in candidates screened for bariatric surgery. ESS is a useful tool to investigate daytime sleepiness and other manifestations of sleep apnea. However, the ESS does not predict the severity of sleep apnea. Clinical suspicion of sleep apnea should prompt polysomnography.

An octakis-intercalating molecule.

Herein we report the synthesis and characterization of a polyintercalator with eight potential intercalating l,4,5,8-naphthalenetetracarboxylic diimide (NDI) units linked in a head-to-tail arrangement via a peptide linker. UV spectroscopy and viscometry measurements indicated the molecule binds to double-stranded DNA with all eight NDI units intercalated simultaneously. Competition dialysis and DNAse 1 footprinting studies revealed a preference for GC-rich regions of DNA, and circular dichroism studies revealed significant distortion of B-form DNA upon binding. Our so-called "octamer" represents, to the best of our knowledge, the first intercalator that binds as an octakis-intercalator, capable of spanning at least 16 base pairs of DNA.

Frequency with which surgeons undertake pancreaticoduodenectomy determines length of stay, hospital charges, and in-hospital mortality.

Others have suggested that in certain technically challenging operations, outcome and experience are related. Because pancreaticoduodenectomy is a technically complex procedure, this study was undertaken to evaluate mortality, length of hospital stay, and hospital charges when compared to volume of experience. The database of the State of Florida Agency for Health Care Administration was queried for pancreaticoduodenectomies undertaken during a recent 33-month period. Length of stay, hospital charges, and in-hospital mortality were stratified by the frequency of pancreaticoduodenectomy. A total of 282 surgeons performed 698 pancreaticoduodenectomies over 33 months. Eighty-nine percent of surgeons performed one pancreaticoduodenectomy per year or less and accounted for 52% of the procedures. Overall mortality rate was 5.1%. Average hospital charges were $72,171.64. The more frequently pancreaticoduodenectomy was undertaken, the shorter the hospital stay (P = 0.025, regression analysis) and the lower the hospital charges (P = 0.008, regression analysis) and in-hospital mortality (P = 0.036, log likelihood ratio test). Surgeons who undertake pancreaticoduodenectomy more frequently have patients with shorter hospital stays, lower hospital charges, and lower in-hospital mortality rates, independent of hospital volume. Variations exist among surgeons and among different areas of the state. Data regarding cost and mortality are available for use in programs of cost and quality improvement.

Medical school curricula do not address obesity as a disease.

BACKGROUND: Obesity and its associated comorbidities have become an epidemic. However, medical school curricula do not address obesity as a disease. We undertook this study to assess medical students' knowledge about obesity before and after exposure to bariatric surgery. METHODS: A 10-item questionnaire that assesses knowledge of etiology, comorbidities, diagnosis, and management of obesity was mailed to all 201 2nd and 3rd year medical students enrolled in USF between 1999-2000. Data are mean +/- sem. Means were compared using t-test; p < or = 0.05 was significant. RESULTS: The overall response rate was 80%. The 3rd yr students who rotated on bariatric surgery (n = 24) answered correctly more questions than 55 students who did not rotate (90 +/- 2% vs 79 +/- 2%, p = 0.048). These differences were mainly noted in questions related to clinical management of obesity (p = 0.04). There were no significant differences among responses from 2nd yr students (n = 81) and the subset of 3rd yr students (n = 55) who did not rotate through bariatric surgery. CONCLUSIONS: Medical students' knowledge about obesity is significantly improved by rotation on a bariatric surgery program and not during rotations on other clinical disciplines. Medical school curricula should be changed to reflect the growing epidemic of obesity and enhance students' knowledge about obesity as a disease.

What prognostic factors are important in duodenal adenocarcinoma?

HYPOTHESIS: Survival of patients with adenocarcinoma of the duodenum depends on the ability to perform a complete resection and the tumor stage DESIGN: Retrospective case series. SETTING: Tertiary care referral center. PATIENTS: A cohort of 101 consecutive patients (mean age, 62 years), undergoing surgery for duodenal adenocarcinoma from January 1, 1976, through December 31, 1996. Patients with ampullary carcinoma were specifically excluded. Mean duration of follow-up was 4 years. INTERVENTIONS: Surgery was curative in 68 patients (67%) and palliative in 33 patients (33%). Of the curative group, 50 patients (74%) underwent radical surgery, ie, 30 (60%), pancreaticoduodenectomy; 15 (30%), pylorus-preserving pancreaticoduodenectomy; and 5 (10%), total pancreatectomy. A more limited resection procedure was used in 18 patients (26%) involving a segmental duodenal resection in 15 (83%) and a transduodenal excision in 3 (17%). patient survival, and correlation with patient and tumor variables using univariate and multivariate analysis. RESULTS: Actuarial 5-year survival for the curative group was 54%. Only 1 patient in the unresected group survived beyond 3 years. Nodal metastasis (P = .002), advanced tumor stage (P<.001), positive resection margin (P = .02), and weight loss (P<.001) had a significant negative impact on survival in multivariate analysis. Tumor grade, size, and location within the duodenum had no impact on survival. Patient age and tumor depth of invasion influenced survival in univariate analysis, but lost their prognostic significance in multivariate analysis. CONCLUSIONS: Metastasis to lymph nodes, advanced tumor stage, and positive resection margins are associated with decreased survival in patients with duodenal adenocarcinoma. An aggressive surgical approach that achieves complete tumor resection with negative margins should be pursued. Pancreaticoduodenectomy is usually required for cancers of the first and second portion of the duodenum. Segmental resection may be appropriate for selected patients, especially for tumors of the distal duodenum.

Bariatric surgery. Surgery for weight control in patients with morbid obesity.

Morbid obesity has become a health crisis in the United States. Medical programs developed at nonoperative attempts to lose (and maintain) an adequate weight loss are largely unsuccessful. Bariatric surgery has been proven to be effective at inducing and maintaining a satisfactory weight loss to decrease weight-related comorbidity. Bariatric operations include procedures that decrease mechanically the volume capacitance of the proximal stomach (vertical banded gastroplasty, laparoscopic gastric banding) or decrease the proximal gastric capacitance and establish a partial selective malabsorption (gastric bypass and its modifications, partial biliopancreatic bypass, and duodenal switch with partial biliopancreatic bypass). These operations should induce a loss of at least 50% (or more) of excess body weight. Not all patients are candidates for these procedures, and the best results are obtained by a multidisciplinary team (including nutritionist, physician, dietitian, psychologist or psychiatrist interested in eating disorders, and surgeon).

Gastroesophageal reflux after intact vertical banded gastroplasty: correction by conversion to Roux-en-Y gastric bypass.

Symptomatic gastroesophageal reflux disease is common in our experience after vertical banded gastroplasty. Our aim was to determine the safety and efficacy of Roux-en-Y gastric bypass in the treatment of symptomatic gastroesophageal reflux disease complicating vertical banded gastroplasty. We evaluated prospectively collected data on 25 patients who underwent revisional bariatric surgery because of severe gastroesophageal reflux disease after vertical banded gastroplasty. Only 4 of 25 patients had gastroesophageal reflux disease symptoms prior to vertical banded gastroplasty. Endoscopic findings in 24 patients included esophagitis (58%), Barrett's esophagus (28%), pouchitis (29%), and gastritis (21%);7 (28%) of 25 patients had evidence of stenosis at the pouch outlet. Mean follow-up (complete in all 25) after Roux-en-Y gastric bypass was 37 +/- 7 months (range 3 to 102 months). There were no deaths. Postoperative complications occurred in six patients: pneumonia in two, wound infection in two, prolonged drainage of the defunctionalized stomach via gastrostomy in one, and fever in one. Median hospitalization was 7 days (range 5 to 43 days). At follow-up (37 +/- 7 months), 24 (96%) of 25 are completely or almost completely symptom free. Body mass index was 33 +/- 2 kg/m(2) before and 28 +/- 2 kg/m(2) after Roux-en-Y gastric bypass (P = 0. 001). Symptoms of gastroesophageal reflux disease are common after vertical banded gastroplasty. Conversion to Roux-en-Y gastric bypass is safe, relieves gastroesophageal reflux disease, and promotes further weight loss. Moreover, maladaptive eating (vomiting, and so forth) induced by vertical banded gastroplasty is relieved.

Malabsorptive procedures for severe obesity: comparison of pancreaticobiliary bypass and very very long limb Roux-en-Y gastric bypass.

The aim of this study was to determine the efficacy and safety of two malabsorptive procedures for severe obesity. Prospectively collected data from eight men and three women who underwent partial biliopancreatic bypass (PBB) and 19 men and seven women who underwent very very long limb Roux-en-Y gastric bypass (VVLGB) for superobesity (preoperative weight >225% above ideal body weight) were evaluated. Age (42 +/- 3 years and 40 +/- 2 years), body mass index (64 +/- 4 kg/m(2) and 67 +/- 3 kg/m(2)), and percentage of excess body weight (183% +/- 17% and 203% +/- 12%) were similar (mean +/- standard error of the mean). Median follow-up was 96 months (range 72 to 108 months) and 24 months (range 18 to 60 months) for the PBB and VVLGB groups, respectively. Weight loss expressed as percentage of excess body weight was 68% +/- 4% 2 years and 71% +/- 5% 4 years after PBB, and 53% +/- 7% 2 years and 57% +/- 5% 4 years after VVLGB. Current body mass indexes are 37 +/- 2 kg/m(2) and 42 +/- 2 kg/m(2) in the PBB and VVLGB groups, respectively. Hospital mortality was zero. Morbidity occurred in five patients after VVLGB (wound infection in four, wound seroma in one, and pulmonary embolus in one) and in two patients after PBB (abscess in two, anastomotic leak in one, and gastrointestinal bleeding in one). After PBB, one woman died of refractory liver failure 18 months postoperatively and two other patients developed metabolic bone disease. No such known complications have occurred to date after VVLGB. We conclude that VVLGB is safe and effective for clinically significant obesity, results in sustained weight loss, and improves quality of life.

Near-total completion gastrectomy for severe postvagotomy gastric stasis: analysis of early and long-term results in 62 patients.

The aim of this study was to evaluate results of completion gastrectomy for severe postgastrectomy gastric stasis. A total of 51 women and 11 men underwent completion gastrectomy for gastric stasis between 1985 and 1996; follow-up was complete in 98% at 5.4 +/- 5 years. All patients had modified Visick scores preoperatively of grade III (37%) or IV (63%). Presentation included combinations of nausea, vomiting, postprandial pain, chronic abdominal pain, and chronic narcotic use. All had undergone prior vagotomy and had a median of four previous gastric operations. Hospital mortality was zero. Complications occurred in 25 patients (40%) and included the following: narcotic withdrawal syndrome (18%), ileus (10%), wound infection (5%), intestinal obstruction (2%), and anastomotic leak (5%). All or most symptoms were relieved in 43% (Visick grade I or II), but 57% of the patients remained in Visick grade III or IV. Nausea, vomiting, and postprandial pain were reduced from 93% to 50%, 79% to 30%, and 58% to 30%, respectively (P<0.05), but chronic pain, diarrhea, and dumping syndrome were not significantly affected. Univariate analysis revealed no preoperative characteristic to be predictive of good outcome. Logistic regression analysis suggested that the combination of nausea, need for total parenteral nutrition, and retained food in the stomach predicted a poor outcome (P<0.05). Completion gastrectomy is successful in 43% of patients. The combination of nausea, need for total parenteral nutrition, and retained food at endoscopy are negative prognostic factors.

Long-term results of biliary reconstruction after laparoscopic bile duct injuries.

HYPOTHESIS: The Hepp-Couinaud approach to biliary enteric reconstruction for laparoscopic bile duct injuries provides a durable, long-term result in most patients. DESIGN: Retrospective study of patients who underwent operative repair of laparoscopic bile duct injuries from January 1990 through December 1997. SETTING: Academic tertiary referral center. MAIN OUTCOME MEASURES: Outcome was assessed using a grading system based on clinical symptoms, liver function tests, and need for reintervention for anastomotic stricture. The Kaplan-Meier method was employed to estimate stricture-free survival. RESULTS: Fifty-nine consecutive patients underwent operative repair of the following laparoscopic bile duct injuries (Strasberg classification): B: n = 2 (3%), C: n = 1 (1%), D: n= 2 (3%), E1: n= 5 (8%), E2: n= 16 (27%), E3: n= 25 (42%), E4: n = 5 (8%), and E5: n = 3 (5%). Forty-seven patients (80%) had 1 or more interventions prior to the index repair. The extrahepatic left bile duct (Hepp-Couinaud approach) was used in 46 of 53 patients who underwent a Roux-en-Y hepaticojejunostomy. Follow-up (mean+/-SEM, 3.7+/-0.3 years) was complete in 54 of the 57 patients still alive. Five patients developed subsequent anastomotic strictures and were treated with percutaneous transhepatic dilation (n = 3), endoscopic dilation (n = 1), and operative revision (n= 1). Excellent to good long-term results were achieved in the remaining 49 patients (91%). Life-table analysis yielded 95% and 88% chances of stricture-free survival at 2 and 5 years, respectively. CONCLUSIONS: Complex iatrogenic proximal bile duct injuries and strictures are amenable to operative repair using the extrahepatic left bile duct. The Hepp-Couinaud approach offers a durable result in more than 90% of patients, even after previous interventions have failed.

An end-to-end pancreaticojejunostomy using a mechanical purse-string device.

Pancreatic-jejunal anastomosis leaks are a major cause of morbidity and mortality after pancreaticoduodenectomy. We have used a mechanical purse-string device to secure the jejunum to the intussuscepted pancreatic stump in 17 patients. A major leak developed in 1 patient and minor leaks developed in 2 patients, all of which were managed nonoperatively. This technique is expeditious and safe.

Role of nitric oxide, vasoactive intestinal polypeptide, and ATP in inhibitory neurotransmission in human jejunum.

BACKGROUND: Inhibitory neurotransmission in the human intestine is poorly understood. This study was undertaken to determine the role of nitric oxide (NO), adenosine triphosphate (ATP), and vasoactive intestinal polypeptide (VIP) in inhibitory neurotransmission in human jejunal circular muscle strips. METHODS: In vitro response of precontracted (10(-5) M substance P) normal human jejunal muscle strips to electric field stimulation (EFS) under adrenergic and cholinergic receptor blockade was evaluated. Selective neural blockade was obtained by the NO synthase inhibitor l-NG-nitroarginine methyl ester (l-NAME, 10(-3) M), VIP receptor antagonist (4-Cl-d-Phe6Leu17-VIP, 10(-7) M), P2 purinergic receptor blocker suramin (3 x 10(14) M), or the calcium-dependent potassium channel blocker apamin (10(-6) M). Force generated in response to EFS was quantitated and analyzed statistically. RESULTS: Exogenous NO and ATP dose-dependently inhibited contractile activity and relaxed muscle strips with a concentration yielding a 50% effect (ED50) of 4.5 +/- 2.9 x 10(-6) M and 3.3 +/- 1.3 x 10(-4) M, respectively. EFS resulted in relaxation of precontracted muscle strips in all groups. When compared with controls, relaxation was decreased but not abolished by l-NAME (-0.12 +/- 0.03 vs -0.33 +/- 0. 05, -0.07 +/- 0.03 vs -0.34 +/- 0.05, and 0.04 +/- 0.03 vs -0.30 +/- 0.04 at 2, 5, and 10 Hz, respectively, P < 0.011). d-NAME (inactive stereoisomer of l-NAME), 4-Cl-d-Phe6Leu17-VIP, suramin, and apamin did not alter EFS-induced relaxation. CONCLUSIONS: Inhibition of NO synthesis by l-NAME reduced the inhibitory response to EFS, whereas blocking ATP and VIP receptors or other effector pathways had no effect. Our findings indicate that although NO plays a predominant role in inhibitory neurotransmission in human jejunal circular muscle, another neurotransmitter(s) appears to be involved as well. These data may impact on understanding mechanisms of disorders of gut dysmotility.

Financial status does not predict weight loss after bariatric surgery.

BACKGROUND: Lower socioeconomic status and poor funding are thought to be associated with suboptimal outcome after bariatric surgery. We undertook this study to determine if funding status is a predictor of outcome in patients undergoing bariatric surgery. METHODS: The medical records of 131 consecutive patients who underwent vertical banded gastroplasty (VBG) for clinically severe obesity (BMI >40 kg/m2) were reviewed. Patients were divided into three groups based on insurance status: (1) commercially insured/traditional indemnity programs; (2) entitlement programs (Medicare), and (3) medically indigent (Medicaid or no funding). Data is mean +/- SD. Data was analyzed using ANOVA and Student t-test. RESULTS: The three groups had similar preoperative weight. Mean BMI was 39 +/- 13, 42 +/- 15, 41 +/- 11 at 1 year, and 40 +/- 13, 43 +/- 16, 45 +/- 16 at 2 years postoperatively for the insured, entitlement, and indigent groups, respectively. CONCLUSION: After standard preoperative evaluation and screening, patients loss weight following VBG independent of insurance status. Source of funding should, therefore, not preclude patients from undergoing bariatric surgery. Patients with limited financial resources can expect similar outcomes as patients with commercial insurance.

Contractile activity of circular smooth muscle in rats one year after small bowel transplantation: differing adaptive response of the jejunum and ileum to denervation.

The aim of the present study was to determine the long-term effects of isogeneic small bowel transplantation (SBT) on jejunal and ileal circular smooth muscle contractile activity in the rat. Transmural strips of circular muscle were prepared from proximal jejunum and distal ileum of 1-year-old control rats and rats 1 year after SBT (SBT-1Y) to measure isometric force. Spontaneous contractile activity and the dose-responses to bethanechol and norepinephrine were studied. Electrical field stimulation (EFS) at varying frequencies (1 to 20 Hz) was evaluated under adrenergic and cholinergic blockade to investigate inhibitory nerves. Spontaneous activity both in the jejunum and ileum in SBT-1Y rats was not different compared to control rats. Sensitivity to bethanechol did not differ between control and SBT-1Y rats in the jejunum or ileum. Sensitivity to norepinephrine, however, was significantly increased after SBT in the ileum but not in the jejunum. During EFS, inhibition was seen at low frequencies, and contractions were induced at high frequencies in all groups. The degree of inhibition did not differ between control and SBT-1Y rats in the jejunum; however, it tended to be increased in the ileum after SBT. The long-term adaptive response of smooth muscle to the extrinsic denervation accompanying SBT differs between the jejunum and the ileum.

In situ neural isolation of the entire canine upper gut: effects on fasting and fed motility patterns.

BACKGROUND: Multiorgan upper gut transplantation is becoming clinically feasible; however, the effects of multivisceral transplantations on gastrointestinal motility are unknown. Our aim was to determine the neural and hormonal mechanisms controlling motility patterns after complete extrinsic denervation of the upper gut as a model of multivisceral upper gut autotransplantation. METHODS: Seven dogs successfully underwent in situ neural isolation of the stomach, entire small intestine, proximal colon, liver, and pancreas by transecting all connections (distal esophagus, midcolon, all nerves, lymphatics) to this multivisceral complex except the celiac artery, superior mesenteric artery, and the suprahepatic and infrahepatic vena cava; these vessels were meticulously stripped of adventitia under optical magnification. Blood flow was not disrupted to prevent confounding effects of ischemia-reperfusion injury. After 1- to 2-week recovery, myoelectric and manometric recordings of stomach and myoelectric recordings of small bowel were obtained from conscious animals. RESULTS: During fasting the characteristic cycling migrating motor complex (MMC) was observed in the stomach and small intestine. The gastric component of the MMC was absent in one of the seven dogs. Regular cycling of the MMC during fasting, however, was intermittently disrupted and replaced by a noncyclic pattern of intermittent contractions in two of seven dogs 43% of the recording time. A small meal (50 gm liver) did not abolish the MMC as occurs in normal dogs; in contrast, a large meal (500 gm liver) did abolish the MMC. CONCLUSIONS: Extrinsic innervation to the upper gut modulates but is not requisite for interdigestive and postprandial motility of the stomach. Because relatively normal global motility patterns are preserved, multivisceral upper gut transplantation should be a viable option in selected patients.