Effect of PGG-glucan on the rate of serious postoperative infection or death observed after high-risk gastrointestinal operations. Betafectin Gastrointestinal Study Group.

BACKGROUND: Postoperative infections remain common after high-risk gastrointestinal procedures. PGG-glucan (Betafectin; Alpha Beta Technology Inc, Worcester, Mass), derived from yeast cell walls, promotes phagocytosis and intracellular killing of bacterial pathogens by leukocytes, prevents infection in an animal model of wound infection, and acts synergistically with antibiotics to reduce mortality in rat peritonitis. HYPOTHESIS: We hypothesized that infectious complications in these patients might be reduced by the administration of a nonspecific immune-enhancing agent. DESIGN: Multicenter, prospective, randomized, double-blind, placebo-controlled trial of 1249 patients prospectively stratified into colorectal or noncolorectal strata. SETTING: Thirty-nine medical centers throughout the United States. PATIENTS: Aged 18 years or older, scheduled for gastrointestinal procedure lasting 2 to 8 hours, with 2 or more defined risk factors. INTERVENTIONS: PGG-glucan, 0.5 mg/kg or 1.0 mg/kg, or placebo once preoperatively and 3 times postoperatively. All patients received standardized antibiotic prophylaxis. MAIN OUTCOME MEASURES: Serious infection or death within 30 days. RESULTS: All randomized patients revealed no difference in serious infections and deaths in the treated groups compared with placebo groups (15% vs 14%, P>.90). In the prospectively defined noncolorectal stratum (n = 391), PGG-glucan administration was associated with a statistically significant relative reduction (39%) in serious infections and death (placebo, 46 [36%] of 129 vs either PGG-glucan group, 29 [21%] of 132 and 28 [22%] of 130, P<.02). PGG-glucan reduced postoperative infection or death in malnourished patients having noncolorectal procedures (31 [44%] of 70, placebo group; 16 [24%] of 68, 0.5-mg/kg PGG-glucan group; 12 [17%] of 72, 1.0-mg/kg PGG-glucan group; P<.001). Study drug was stopped owing to adverse effects more frequently for patients receiving PGG-glucan than placebo (2%, 4%, and 7% for the placebo group, 0.5-mg/kg PGG-glucan group, and 1.0-mg/kg PGG-glucan group, respectively, P<.003). CONCLUSION: Perioperative administration of PGG-glucan reduced serious postoperative infections or death by 39% after high-risk noncolorectal operations.

Carcinoma of the extrahepatic biliary tract: surgery and radiotherapy for curative and palliative intent.

Forty-seven patients were treated for carcinoma of the extrahepatic biliary tract between 1962 and 1993: 17 by surgery alone, 20 by surgery and postoperative radiotherapy, and 10 with radiotherapy alone. Initial operations included gross total resection (17 patients), simple cholecystectomy (6 patients), subtotal resection (11 patients), biopsy (3 patients), and percutaneous decompression (10 patients). External-beam radiotherapy (30-60 Gy) was administered to 30 patients: 10 after gross total resection or simple cholecystectomy, 10 after subtotal resection or surgical biopsy, and 10 after percutaneous decompression. Overall survival was 26% at 3 years and 15% at 5 years. The 5-year survival rate was 15% for 17 patients treated by surgery alone and 14% for 30 patients treated with radiotherapy alone or following surgery. After gross total resection, median survival time was 26.1 months for 9 patients treated by surgery alone vs. 43.4 months for 8 patients who received postoperative radiotherapy. After gross total resection or cholecystectomy, 5-year survival rates were 19% for surgery alone and 35% for surgery and postoperative radiotherapy (P=.07). Median survival for 10 patients treated by radiation therapy alone after percutaneous decompression was 6.4 months. Postoperative adjuvant radiotherapy was well tolerated and may improve local-regional control after gross total resection.

A randomized, double-blind clinical trial comparing cefepime plus metronidazole with imipenem-cilastatin in the treatment of complicated intra-abdominal infections. Cefepime Intra-abdominal Infection Study Group.

OBJECTIVE: To evaluate the safety and efficacy of cefepime hydrochloride plus metronidazole vs the combination of imipenem and cilastatin sodium in the treatment of complicated intra-abdominal infections in adult patients. DESIGN: Prospective, randomized, double-blind multicenter study. SETTING: University-affiliated hospitals in the United States and Canada. PATIENTS: Three hundred twenty-three patients with complicated intra-abdominal infections in whom an operative procedure or percutaneous drainage was required for diagnosis and management. INTERVENTION: Cefepime, 2 g, was administered intravenously every 12 hours (n= 164) in addition to metronidazole, 500 mg (or 7.5 mg/kg) intravenously every 6 hours. Imipenen-cilastatin sodium, 500 mg, was administered intravenously every 6 hours (n= 159). Surgical infection management was determined by the patients' surgeons. MAIN OUTCOME ASSESSMENTS: Clinical cure, defined as elimination of all signs and symptoms relevant to the original infection; and treatment failure, defined as persistence, increase or worsening of signs and symptoms resulting in an antibiotic change, requirement of an additional surgical procedure to cure the infection, or a wound infection with fever. RESULTS: Of the initial isolates, 84% were susceptible to cefepime and 92% were susceptible to imipenem-cilastatin. Among the 217 protocol-valid patients, those treated with cefepime+metronidizole were deemed clinical cures (88%) more frequently than were imipenem-cilastatin-treated patients (76%) (P=.02). Using multivariate analysis to adjust for identified clinical risk factors for an adverse outcome (severity of presenting illness, isolation of enterococcus, type of infection, and duration of prestudy hospitalization), there was a trend (P=.06) toward a higher cure rate favoring cefepime+metronidazole. Pathogens were eradicated in significantly (P=.01) more patients treated with combined cefepime and metronidazole (89%) than with imipenem-cilastatin (76%). CONCLUSION: The combination of cefepime plus metronidazole is safe and effective therapy for patients with severe intra-abdominal infections.

Results of a randomized trial comparing sequential intravenous/oral treatment with ciprofloxacin plus metronidazole to imipenem/cilastatin for intra-abdominal infections. The Intra-Abdominal Infection Study Group.

OBJECTIVE: In a randomized, double-blind, multicenter trial, ciprofloxacin/metronidazole was compared with imipenem/cilastatin for treatment of complicated intra-abdominal infections. A secondary objective was to demonstrate the ability to switch responding patients from intravenous (IV) to oral (PO) therapy. SUMMARY BACKGROUND DATA: Intra-abdominal infections result in substantial morbidity, mortality, and cost. Antimicrobial therapy often includes a 7- to 10-day intravenous course. The use of oral antimicrobials is a recent advance due to the availability of agents with good tissue pharmacokinetics and potent aerobic gram-negative activity. METHODS: Patients were randomized to either ciprofloxacin plus metronidazole intravenously (CIP/MTZ IV) or imipenem intravenously (IMI IV) throughout their treatment course, or ciprofloxacin plus metronidazole intravenously and treatment with oral ciprofloxacin plus metronidazole when oral feeding was resumed (CIP/MTZ IV/PO). RESULTS: Among 671 patients who constituted the intent-to-treat population, overall success rates were as follows: 82% for the group treated with CIP/MTZ IV; 84% for the CIP/MTZ IV/PO group; and 82% for the IMI IV group. For 330 valid patients, treatment success occurred in 84% of patients treated with CIP/MTZ IV, 86% of those treated with CIP/MTZ IV/PO, and 81% of the patients treated with IMI IV. Analysis of microbiology in the 30 patients undergoing intervention after treatment failure suggested that persistence of gram-negative organisms was more common in the IMI IV-treated patients who subsequently failed. Of 46 CIP/MTZ IV/PO patients (active oral arm), treatment success occurred in 96%, compared with 89% for those treated with CIP/MTZ IV and 89% for those receiving IMI IV. Patients who received intravenous/oral therapy were treated, overall, for an average of 8.6 +/- 3.6 days, with an average of 4.0 +/- 3.0 days of oral treatment. CONCLUSIONS: These results demonstrate statistical equivalence between CIP/MTZ IV and IMI IV in both the intent-to-treat and valid populations. Conversion to oral therapy with CIP/MTZ appears as effective as continued intravenous therapy in patients able to tolerate oral feedings.

Salsalate, morphine, and postoperative ileus.

BACKGROUND: Previously, we demonstrated that ketorolac, a nonsteroidal antiinflammatory drug (NSAID), prevented postoperative small bowel ileus in a rodent model. The aim of this study was to evaluate the effect of salsalate, an NSAID without antiplatelet effect, on postoperative ileus alone or in combination with morphine. METHODS: Forty-eight rats underwent placement of duodenal catheters and were then randomly assigned to one of eight groups (n = 6). Four groups had standardized laparotomy following drug administration, whereas 4 groups underwent the same treatment without laparotomy: control and morphine animals received 0.1 mL alcohol via the catheter, whereas salsalate and salsalate-plus-morphine animals received salsalate (15 mg/kg) dissolved in 0.1 mL alcohol. The animals also received 0.5 mg/kg morphine (morphine and salsalate plus morphine) or the same volume of saline (control and salsalate) subcutaneously. Transit was measured following the injection of a nonabsorbed marker via the duodenal catheter and is defined as the geometric center (GC) of distribution. An additional 20 rats had serosal electrodes placed on the jejunum, and were assigned to one of four treatment groups (control, salsalate, morphine, and salsalate plus morphine; n = 5 each group). Myoelectric activity was recorded until the reappearance of the migrating myoelectric complex (MMC) following laparotomy. RESULTS: Laparotomy and morphine independently reduced small bowel transit (P = 0.0006 and 0.006, respectively, by three-way analysis of variance [ANOVA]; GC 4.3 +/- 0.2 control versus 2.2 +/- 0.3 laparotomy versus 3.6 +/- 0.4 morphine), but morphine did not further worsen postoperative transit (GC 2.4 +/- 0.4; P = 0.42). Although salsalate did not alter baseline transit, pretreatment improved postoperative transit (P = 0.0002; GC 3.6 +/- 0.4). This effect was lost with the addition of morphine (GC 2.7 +/- 0.2; P = 0.21). The MMCs returned earlier after laparotomy in salsalate-pretreated rats (63 +/- 18 minutes salsalate versus 160 +/- 12 minutes laparotomy; P < 0.01, one-way ANOVA). However, this effect was also lost in animals receiving morphine (106 +/- 16 min; P > 0.05). CONCLUSION: Salsalate improves postoperative small bowel motility in a rodent model; however, this effect is masked by morphine.

Definition of the role of enterococcus in intraabdominal infection: analysis of a prospective randomized trial.

BACKGROUND: The role of enterococcus in intraabdominal infection is controversial. This study examines the contribution of enterococcus to adverse outcome in a large intraabdominal infection trial. METHODS: A randomized prospective double-blind trial was performed to compare two different antimicrobial regimens in combination with surgical or percutaneous drainage in the treatment of complicated intraabdominal infections. A total of 330 valid patients was enrolled from 22 centers in North America. RESULTS: In 330 valid patients, 71 had enterococcus isolated from the initial drainage of an intraabdominal focus of infection. This finding was associated with a significantly higher treatment failure rate than that of patients without enterococcus (28% versus 14%, p < 0.01). In addition, only Acute Physiology and Chronic Health Evaluation II score and presence of enterococcus were significant independent predictors of treatment failure when stepwise logistic regression was performed (p < 0.01 and < 0.03). Risk factors for the presence of enterococcus include age, Acute Physiology and Chronic Health Evaluation II, preinfection hospital length of stay, postoperative infections, and anatomic source of infection. There was no difference between the clinical trial treatment regimens with regard to overall failure, failure associated with enterococcus, or frequency of enterococcal isolation. CONCLUSIONS: This study is the first to report enterococcus as a predictor of treatment failure in complicated intraabdominal infections. This trial also identifies several significant risk factors for the presence of enterococcus in such infections.

The effect of Roux-en-Y diversion on gastric and Roux-limb emptying in a rodent model.

BACKGROUND: The "Roux stasis syndrome" is characterized by symptoms of upper gut stasis following Roux-en-Y gastrojejunostomy (RG). Whether symptoms result from delayed gastric emptying, altered Roux-limb transit, or both has never been settled, partly because of the difficulty of measuring Roux-limb transit. The aim of this study was to develop a model to simultaneously quantitate Roux-limb transit and gastric emptying. METHODS: Rats underwent vagotomy and antrectomy with RG or Billroth II reconstruction (B-II). Gastrointestinal transit of a solid meal (Technetium-99m sulfur colloid-labelled egg white) was assessed 0.5, 1, and 1.5 hours postprandial (pp). Transit of a liquid marker (Na51-CrO4 injected through an efferent-limb catheter) was measured at 25 minutes pp. RESULTS: Solid gastric emptying was slower in RG than in B-II rats at 60 and 90 minutes pp. More of the solid meal and of the liquid marker was retained in the Roux limb than the efferent limb of the B-II at all time points (P < 0.05). CONCLUSIONS: In a rodent model, Roux-en-Y gastrojejunostomy is associated with delayed gastric emptying and slowed efferent-limb transit of solids and liquids.

Vasoactive intestinal peptide and substance P receptor antagonists improve postoperative ileus.

Octreotide, a somatostatin analogue that inhibits the release of most gut peptides, hastens the resolution of experimental postoperative ileus, suggesting that gut peptides mediate this process. We studied the role of two gut peptides involved in the control of normal gut motility, vasoactive intestinal peptide (VIP), and substance P (SP), in the initiation and maintenance of postoperative small bowel ileus in rats by preoperative administration of VIP and SP receptor antagonists, (VIP-ra and SP-ra). Thirty male Sprague-Dawley rats (300-350 g) underwent laparotomy. One half underwent placement of a duodenal catheter for transit studies while the other half had serosal electrodes placed on the proximal jejunum for myoelectric recordings. Six days later, animals were separated into three treatment groups of five each. Control animals were pretreated with ip saline, while the others received either VIP-ra or SP-ra prior to standardized laparotomy. Following abdominal closure, [Na51]CrO4 was injected into the duodenum and the animals were sacrificed 25 min later. The small bowel was then excised and divided into 10 equal segments. Small bowel transit was calculated as the geometric center of [Na51]CrO4 distribution. The interval until the return of migrating myoelectric complexes (MMCs) was determined in animals with intestinal electrodes. VIP-ra-treated rats demonstrated a 67% improvement in the geometric center of radiolabel relative to controls and SP-ra-treated rats had a 23% improvement (3.67 +/- 0.06 VIP-ra vs 2.69 +/- 0.09 SP-ra vs 2.20 +/- 0.09 control, P < 0.01). MMCs returned 180 +/- 17 min in controls vs 99 +/- 14 min in VIP-ra-treated rats (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Downstaging of esophageal cancer after preoperative radiation and chemotherapy.

OBJECTIVE: This retrospective, nonrandomized review evaluates 125 patients with esophageal carcinoma (adenocarcinoma and squamous cell) who underwent either surgery only or preoperative chemotherapy and/or radiation therapy followed by surgery. Major end points were survival and postchemoradiation downstaging. METHODS: Forty-four patients underwent radiation therapy of 4500 cGy over 5 weeks. Fluorouracil and cisplatin were administered on the first and fifth week of radiotherapy. Ninety-eight patients underwent "potentially curative" resections-transhiatal esophagectomy (70), Lewis esophagogastrectomy (25), and left esophagogastrectomy (3). All patients with preoperative adjuvant therapy underwent endoscopy and biopsy before surgery. RESULTS: There were no differences in overall mortality (5%) or surgical complications in either group. Fourteen of 44 patients (32%) downstaged to complete pathologic response, with 5-year survival of 57%. Fifteen of 44 patients (34%) downstaged to microscopic residual tumor, with 1- and 3-year survival of 77% and 31%, respectively. Twenty-eight of 29 patients in the two downstaged groups were lymph node negative. Overall, 5-year survival in the adjuvant therapy plus surgery group versus surgery only was 36% and 11% (p = 0.04). Five-year survival in lymph node-negative adjuvant therapy and surgery patients was 49% (p = 0.005). Positive nodes in the surgery only group was 48% versus 23% in the adjuvant therapy and surgery group (p = 0.02). CONCLUSION: Although retrospective and nonrandomized, these results suggest that preoperative chemoradiation results in significant clinical and pathologic downstaging, increases survival, and may sterilize local and regional lymph nodes, accounting for both downstaging and survival statistics.

Efferent limb myoneural and luminal continuity and postgastrectomy gastric emptying.

Delayed gastric emptying and altered upper gut transit or both are common following Roux-en-Y gastrojejunostomy and are thought to be due to altered efferent limb transit secondary to isolation of the Roux limb from the duodenal pacemaker. We postulated that preservation of myoneural continuity of the Roux limb with the duodenal pacemaker would enhance solid gastric emptying, while division of the afferent limb of a Billroth II gastrojejunostomy (B-II), isolating the efferent jejunal limb from the duodenal pacemaker, would slow gastric emptying. Solid gastric emptying was measured in 14 dogs, who then underwent gastric vagotomy and antrectomy. Eight animals were reconstructed with a Roux-en-Y gastrojejunostomy, preserving myoneural but not luminal continuity of the Roux limb with the afferent limb via a muscularis bridge, while six dogs underwent standard B-II gastrojejunostomy. Serosal electrodes were placed on the afferent and efferent jejunal limbs. Gastric emptying was restudied, with fed and fasted myoelectric recordings. The bridge was then divided to create a standard Roux, while the afferent limb was transected and reanastomosed just proximal to the gastrojejunostomy in the B-II dogs to isolate the efferent limb from the duodenal pacemaker, with repeat studies. Bridge dogs had delayed solid gastric emptying compared to their preoperative state, despite normal efferent limb motility.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnosis of pancreatic cancer and prediction of unresectability using the tumor-associated antigen CA19-9.

Marked elevations of the tumor-associated antigen CA19-9 are relatively specific for pancreatic carcinoma and are associated with more advanced malignancies. We retrospectively reviewed 53 patients with CA19-9 values > 90 U/ml in whom the test had been done because of clinical suspicion of pancreatic malignancy. Pancreatic cancer was found in 45 patients (85%). If a cutoff value of CA19-9 > 200 U/ml is used, 36 of 37 (97%) patients had pancreatic cancer. Thirty patients with pancreatic cancer and no radiographic criteria of unresectability underwent attempted resection; five of these patients were judged to be potentially resectable and four of them underwent attempted resection. In only one patient with a CA19-9 value > 300 U/ml was resection possible; this patient had advanced carcinoma. Our results suggest that, in patients in whom the clinician suspects pancreatic carcinoma, CA19-9 > 90 U/ml is highly suggestive of pancreatic malignancy, while CA19-9 > 200 U/ml is virtually diagnostic of pancreatic malignancy. In similar patients with CA19-9 > 300 U/ml, resection is rarely possible and tumors are advanced.

Clinical and radionuclide evaluation of bile diversion by Braun enteroenterostomy: prevention and treatment of alkaline reflux gastritis. An alternative to Roux-en-Y diversion.

UNLABELLED: OBJECTIVE AND SUMMARY BACKGROUND: Symptomatic, medically resistant postgastrectomy patients with alkaline reflux gastritis (ARG) have increased enterogastric reflux (EGR) documented by quantitative radionuclide biliary scanning. Even asymptomatic patients after gastrectomy have increased EGR compared with nonoperated control patients. Roux-en-Y biliary diversion, although successfully treats the clinical syndrome of ARG, has a high incidence of early and late postoperative severe gastroparesis, Roux limb retention (the Roux syndrome), or both, which often requires further remedial surgery. As an alternative to Roux-en-Y diversion, this review evaluates the efficacy of the Braun enteroenterostomy (BEE) in diverting bile away from the stomach in patients having gastric operations. Based on previous pilot studies, the BEE is positioned 30 cm from the gastroenterostomy. METHODS: Thirty patients had the following operations and were evaluated: standard pancreatoduodenectomy (8), vagotomy and Billroth II (BII) gastrectomy (6), BII gastrectomy only (10), and palliative gastroenterostomy to an intact stomach (6). All anastomoses were antecolic BII with a long afferent limb and a 30-cm BEE. Four symptomatic patients with medically intractable ARG and chronic gastroparesis had subtotal BII gastric resection with BEE rather than Roux-en-Y diversion. Eight control symptomatic patients and six asymptomatic patients with previous BII gastrectomy and no BEE were evaluated. Radionuclide biliary scanning was performed within 30 days in all patients and at 4 to 6 months in 14 patients. Bile reflux was expressed as an EGR index (%). RESULTS: After operation, 18 of 34 patients (53%) had no demonstrable EGR while in the fasting state for as long as 90 minutes. The range of demonstrable bile reflux (EGR) in the remaining 16 patients was from 2% to 17% (mean, 4.5%). Enterogastric reflux in the 14 control patients (with no BEE) ranged from 5% to 82% (mean, 42%). The four patients with ARG and chronic gastroparesis treated by subtotal gastrectomy and BEE had postoperative EGR of 0%, 2%, 2%, and 4%, respectively. They are asymptomatic with no evidence of bile reflux gastritis. In the 14 patients who had late evaluation, EGR ranged from 0% to 16% (mean, 5.5%). No patient had signs or symptoms of ARG after operation. CONCLUSIONS: Braun enteroenterostomy successfully diverts a substantial amount of bile from the stomach. The ARG syndrome might be prevented by performing BEE during gastric resection or bypass in a variety of operations. Conversion to a BII with BEE may be an alternative to Roux-en-Y diversion in treating medically resistant ARG and subsequent may avoid the Roux syndrome.

Prediction of surgical resectability in patients with hepatic colorectal metastases.

OBJECTIVE: To evaluate the efficacy of two distinct imaging techniques to predict, before operation, unresectability compared with standard computed tomographic scan (CT). SUMMARY BACKGROUND: Accurate preoperative identification of the number, size, and location of hepatic lesions is crucial in planning hepatic resection for colorectal hepatic metastases. Although infusion-enhanced CT is the standard, its limitations are the imaging of relatively isodense and/or small (< 1 cm) lesions. The increased sensitivity of CT arterial portography (CTAP) may be offset by false-positive results caused by benign lesions and flow artifacts. METHODS: Fifty-eight selected patients considered to be eligible for resection by standard CT had laparotomy. Before operation and in addition to CT, all patients had CT arterial portography and hepatic artery perfusion scintigraphy (HAPS) using radiolabeled macroaggregated albumin. Early studies showed an increased sensitivity for detecting small lesions using the invasive CTAP. Similarly, the HAPS study has detected malignant lesions not observed by standard CT. RESULTS: Of 58 patients having laparotomy, 40 were resectable by either lobectomy (22) or trisegmentectomy (1) and the rest by single or multiple wedge resections. Eighteen patients could not be resected because of combined intra- and extrahepatic disease or the number and location of metastases. Standard CT detected 64% of all lesions (12% of lesions less than 1 cm). Unresectability was accurately predicted by CTAP and HAPS in 16 (88%) and 15 (83%), respectively, of the 18 patients considered ineligible for resection at laparotomy. Of the 40 patients who had resection for possible cure, CTAP and HAPS falsely predicted unresectability in 6 of 40 patients (15%) and in 10 of 40 patients (25%), respectively. The positive predictive value for unresectability of CTAP and HAPS was 73% and 60%, respectively. False-positive lesions after CTAP included hemangiomas, cysts, granulomas, and flow artifacts. False-positive HAPS lesions included patients in whom no tumor was found at surgery but with some identified by intraoperative ultrasound, blind biopsy, and blind resection. CONCLUSIONS: False-positive results by HAPS and CTAP may limit the ability of these tests to accurately predict unresectability before operation and may deny patients the chance for surgical resection. The HAPS study does, however, detect small lesions not seen by CT or CTAP. Standard CT, although less sensitive, followed by surgery and intraoperative ultrasound, does not necessarily preclude patients who could be resected.

Human gastric myoelectric activity and gastric emptying following gastric surgery and with pacing.

Postoperative gastric myoelectric activity, gastric emptying, and clinical course were correlated in 17 patients at high risk of developing gastroparesis after gastric surgery. In addition, an attempt was made to pace the stomach with an electrical stimulus and determine the effect of pacing on early postoperative gastric emptying. Gastric dysrhythmias (bradygastria, slow wave frequency < 2 cycles/min; tachygastria, slow wave frequency > 4 cycles/min) persisted beyond the first postoperative day in 6 patients (35%). Delayed gastric emptying was identified by a radionuclide meal in 15 patients (88%), but symptoms of gastroparesis developed in only 6 of 15 (40%). Patients with postoperative gastroparesis had more frequent dysrhythmias than asymptomatic patients (67% vs. 18%), but these differences were not significant, although we cannot exclude a type II statistical error. Gastric rhythm was entrained in 10 of 16 patients (63%). Pacing increased the gastric slow wave frequency (3.1 vs. 4.1 cycles/min; P < 0.01) but did not improve gastric emptying (gastric retention at 60 minutes, 86% +/- 6% for control and 90% +/- 2% for paced). In conclusion, gastric dysrhythmias do not appear to play a major role in the development of postsurgical gastroparesis. Although gastric rhythm could be entrained in the majority of patients, pacing did not improve gastric emptying overall.

Does selective vagotomy prevent delayed gastric emptying and altered myoelectric activity following Roux-en-Y gastrojejunostomy?

Delayed gastric emptying occurs frequently following Roux-en-Y gastrojejunostomy. The role of vagal denervation in the etiology of this "Roux-stasis syndrome" is controversial. This study evaluates the effect of selective vagotomy on gastric emptying and motility following Roux-en-Y. Four dogs underwent control gastric emptying studies. The animals then underwent selective vagotomy, antrectomy, and Billroth II gastrojejunostomy, with placement of serosal electrodes. Gastric emptying was assessed with simultaneous myoelectric recordings, and the animals were converted to Roux-en-Y, followed by repeat studies. Gastric emptying was unchanged following selective vagotomy, antrectomy, and Billroth II gastrojejunostomy (T 1/2: 132 +/- 18 min [SEM] versus 118 +/- 14 min control) but was markedly delayed following Roux-en-Y diversion (T 1/2: 286 +/- 44 min; p less than 0.01). All animals went into the fed pattern following Billroth II gastrojejunostomy (migrating myoelectric complex [MMC] interval: 326 +/- 6 min postprandial versus 92 +/- 5 min fasting; p less than 0.01), but no fed pattern was recognized in three of four animals following Roux-en-Y diversion (MMC interval: 68 +/- 12 min postprandial versus 62 +/- 1.5 min fasting; p = NS). In a canine model, selective vagotomy does not prevent delayed gastric emptying or myoelectric alterations following Roux-en-Y.

Antiperistaltic and isoperistaltic intussusception associated with abnormal motility after Roux-en-Y gastric bypass: a case report.

Antiperistaltic and recurrent intussusceptions are extremely rare in the adult. We report a patient with both. The patient developed an antiperistaltic intussusception distal to her Roux enteroenterostomy years after a Roux-en-Y gastric bypass for morbid obesity. The diagnosis was made preoperatively with gastrointestinal contrast radiography and ultrasonography. At surgery, the intussusception was reduced, and 12 inches of nonviable bowel was resected, with a functional end-to-end anastomosis. An isoperistaltic intussusception occurred in the early postoperative period just distal to the anastomosis. Manometric evaluation of the Roux limb after the second operation showed altered gastrointestinal motility, consisting of orad-propagated and aboard-propagated migrating motor complexes, minimal phase 2 activity, and lack of conversion to the fed pattern with a liquid meal. Although manometry was not performed before the development of the intussusception, our findings are consistent with the hypothesis that altered intestinal motility may contribute to the development of intussusception.

Erythromycin acts through a cholinergic pathway to improve canine-delayed gastric emptying following vagotomy and Roux-Y antrectomy.

We have demonstrated that erythromycin improves gastric emptying in dogs following truncal vagotomy and Roux-en-Y antrectomy (VRYA). To explore its mechanism of action we studied gastric emptying and myoelectric activity in a canine Roux model and administered atropine simultaneously with erythromycin. Tachyphylaxis was evaluated following short-term administration. Four dogs with delayed gastric emptying following VRYA were studied. Radionuclide solid gastric emptying was measured, with simultaneous myoelectric recordings obtained from the duodenum and Roux limb. Study groups were: (1) saline control (VRYA dogs); (2) erythromycin 1 mg/kg iv over 1 hr; (3) erythromycin 3 mg/kg po tid for 1 week, with repeat studies using erythromycin 1 mg/kg iv over 1 hr; and (4) atropine 0.5 mg/kg iv bolus, followed by a 1-hr infusion of atropine 0.05 mg/kg and erythromycin 1 mg/kg. Control Roux animals had severe gastric retention (73 +/- 5% at 2 hr, compared to 27 +/- 6% following iv erythromycin (P less than 0.01). Clustered spike bursts were observed in the Roux limb following erythromycin. Atropine abolished the gastrokinetic response and suppressed the myoelectric response to erythromycin (81 +/- 3% retention at 2 hr, P less than 0.01 compared to erythromycin alone). The response to erythromycin was unchanged after 1 week of tid administration (40 +/- 14% retention at 2 hr postprandial, P = NS). Erythromycin improves gastric emptying in VRYA dogs via a cholinergic pathway and does not exhibit tachyphylaxis following short-term administration.

Erythromycin enhances delayed gastric emptying in dogs after Roux-Y antrectomy.

Delayed gastric emptying occurs in up to 50% of patients after truncal vagotomy and Roux-Y antrectomy and is often resistant to nonsurgical therapy. This study evaluates the effect of erythromycin, metoclopramide, and motilin on delayed gastric emptying in four dogs after Roux-Y antrectomy. Solid food gastric emptying was measured using a radionuclide technique. Study groups were: (1) saline control; (2) erythromycin 1 mg/kg intravenously over 1 hour; (3) erythromycin 3 mg/kg by mouth 45 minutes prior to feeding; (4) metoclopramide 0.6 mg/kg intravenously over 1 hour; and (5) motilin 500 ng/kg intravenously over 1 hour. After Roux-Y antrectomy, saline control dogs had 73% +/- 5% (SEM) gastric retention at 2 hours. After intravenous and oral erythromycin, gastric emptying improved at 2 hours to 27% +/- 6% and 39% +/- 5% (p less than 0.01 compared with control). Erythromycin intravenously and by mouth improved gastric emptying compared with metoclopramide (64% +/- 8%, p less than 0.05). Motilin enhanced gastric emptying to a similar degree as erythromycin, with a 2-hour gastric retention of 37% +/- 4% (NS). Erythromycin improved gastric emptying in dogs with severe Roux-Y gastroparesis and may have clinical application.

Gastric emptying and myoelectric activity following Roux-en-Y gastrojejunostomy.

The purpose of this study was to compare gastric emptying and Roux myoelectric activity in a canine model. Four dogs underwent truncal vagotomy, antrectomy, and 40 cm Roux-en-Y gastrojejunostomy, with placement of serosal electrodes. Following recovery, gastric emptying was determined scintigraphically with a radiolabeled solid meal, and fasting and fed small-bowel myoelectric activity was obtained. Gastric emptying was markedly slowed compared to control unoperated animals (202 +/- 91 versus 46 +/- 12 min; P less than 0.05). Slow wave frequency declined in the Roux limb compared to the duodenum (14.2 +/- 0.4 versus 18.0 +/- .06 counts per minute; P less than 0.01). No gradient in slow wave frequency was observed in the Roux limb, although one animal was noted to have reversed propagation of slow waves in the proximal Roux limb. Migrating myoelectric complexes (MMCs) were coordinated between the Roux limb and jejunum distal to the enteroenterostomy, but not with the duodenum. Periodicity of the MMCs was different in the Roux limb and duodenum (98.6 +/- 6.3 versus 138 +/- 17.5 min; P less than 0.05). None of the animals converted to the fed myoelectric pattern with a 272 kcal meal (MMC periodicity in the Roux limb = 99 +/- 10 min postprandially, P = N.S.). These quantitative and qualitative alterations in myoelectric activity may contribute to the observed delay in gastric emptying following Roux-en-Y gastrojejunostomy.