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PubMed1998

The Bagby and Kuslich method of lumbar interbody fusion. History, techniques, and 2-year follow-up results of a United States prospective, multicenter trial.

STUDY DESIGN: A prospective, multicenter trial of the Bagby and Kuslich method of lumbar interbody stabilization for chronic discogenic low back pain, with follow-up evaluation at 3 months, 6 months, and yearly thereafter, with independent radiographic analysis. OBJECTIVES: To report the history of development, the surgical techniques, and results of the Bagby and Kuslich method when used to manage discogenic pain of the lumbar spine in humans. SUMMARY OF BACKGROUND DATA: Disabling chronic low back pain frequently is resistant to conservative management. The "Bagby Basket" effectively has fused the equine and baboon spine. The results of biomechanical and animal studies performed over the last 20 years have suggested that a similar but improved design--the Bagby and Kuslich device--would be useful in stabilizing the human spine. METHODS: From 1992 to 1995, 947 patients with chronic discogenic low back pain were treated by Bagby and Kuslich interbody fusion in a strict, multicenter, prospective clinical trial by using either the open anterior or open posterior approach. The study involved 42 surgeons at 19 medical centers. The authors of the current report analyzed the fusion rates, pain relief, functional status, and complications occurring in patients who underwent long-term follow-up observation. RESULTS: The Bagby and Kuslich method is safe and effective when compared with methods described in previous reports of posterior and anterior lumbar interbody arthrodesis performed by using bone graft alone. Fusion occurred in 91% of patients at 24 months after surgery, and pain was eliminated or reduced in 84%. Function was improved in 91%. There were no device-related deaths, cases of major paralyses, device failures, or deep infections. CONCLUSIONS: Carefully selected middle-aged patients with chronic low back pain secondary to degenerative disc disease can be treated effectively and safely by skilled surgeons using the Bagby and Kuslich device for one- and two-level interbody fusion.

Adult↗
PubMed1999

Safety, tolerability and efficacy of cyclosporine microemulsion in heart transplant recipients: a randomized, multicenter, double-blind comparison with the oil based formulation of cyclosporine--results at six months after transplantation.

BACKGROUND: The introduction of cyclosporine has resulted in significant improvement in the survival of cardiac allograft recipients due to decreased mortality from infection and rejection. The original oil-based cyclosporine formulation exhibits variable and unpredictable bioavailability that correlates with an increased incidence of acute and chronic rejection in those patients in whom this is most pronounced. The primary objectives of this prospective, multicenter, randomized, double-blind study in cardiac transplant patients were: to compare the efficacy of cyclosporine microemulsion (CsA-NL) with oil-based cyclosporine (CsA-SM) as measured by cardiac allograft and recipient survival and the incidence and severity of acute rejection episodes; and to assess the safety and tolerability of CsA-NL compared with CsA-SM in this population. This report represents the analysis of results 6 months after transplantation. METHODS: A total of 380 patients undergoing their first cardiac transplant at 24 centers in the United States, Canada, and Europe were enrolled in this double-blind, randomized trial examining the safety and efficacy of CsA-NL versus CsA-SM. Rejection was diagnosed using endomyocardial biopsy and were graded according to standardized criteria of the International Society of Heart and Lung Transplantation (ISHLT). Clinical parameters were monitored during the study. Survival and freedom from were used for analysis as was Fisher's exact test for comparisons between groups. RESULTS: At 6 months after transplantation, allograft and patient survival were the same for both groups. The frequency of ISHLT grade 3A or greater episodes in the two groups was identical. Fewer CsA-NL patients (5.9%) required antilymphocyte antibody (ATG or OKT-3) therapy for rejection compared with the CsA-SM-treated patients (14.1%, P=0.01). Females with ISHLT rejection grade > or = 3A treated with CsA-NL had a 46% lower incidence of rejection compared with the CsA-SM-treated group (31.3% vs. 57.6%, P=0.032). Fewer infections were seen in the CsA-NL. With the exception of baseline and 1 week posttransplant creatinines which were higher in the CsA-NL group, the overall creatinine was not significantly different between the two groups. CONCLUSIONS: This multicenter, randomized study of cardiac transplant recipients documented less severe rejection (in particular those requiring antibody therapy) and a lower incidence of infection in CsA-NL-treated patients. Results from the female subgroup analysis suggest that the improved bioavailability of CsA-NL might reduce the frequency of rejection episodes in female patients. The use of CsA-NL was not associated with an increased risk of adverse events.

Adolescent↗
PubMed2003

Update on progress in the international, multicenter, randomized, controlled trial of corticosteroids after significant head injury (Medical Research Council CRASH Trial).

PURPOSE OF REVIEW: To provide an update on the progress of the multicenter, randomized, controlled trial of corticosteroids after significant head injury (CRASH). RECENT FINDINGS: After a successful pilot phase, the main phase of the CRASH Trial began in March 2001. By June 2002, 107 hospitals from 31 countries were participating in the trial, and together had recruited 3000 patients. Nine hundred patients (30%) had mild head injury, 885 (30%) had moderate head injury, and 1215 (40%) had severe head injury. A total of 1941 (65%) patients were randomized within 3 hours of injury. Outcome at 2 weeks from injury was known for 2933 (98%) patients, of whom 557 (19%) died. At the time of writing, 6-month follow-up for the first 1500 patients was nearly complete. Vital status was known for 1429 (95%) of the 1500 patients, of whom 313 (22%) had died. Functional status based on the Glasgow Outcome Scale was known for 1391 (93%) of the 1500 patients: 22% were dead, 16% were severely disabled, 23% were moderately disabled, and 39% had made a good recovery. SUMMARY: The CRASH Trial is a randomized, placebo-controlled, multicenter trial of a 48-hour corticosteroid infusion after significant head injury and is now the largest head injury trial ever conducted. The efforts of the national coordinators have shown that it is possible to enroll and follow up very large numbers of head-injured patients.

Adolescent↗
PubMed2001

Further characterization of storage-related alterations in immunoreactivity of archival tissue sections and its implications for collaborative multicenter immunohistochemical studies.

Storage of unstained paraffin slides may lead to the deterioration of specimens and failure to detect cellular proteins immunohistochemically. Although the implication of age-induced alterations on multicenter immunohistochemical studies would be considerable, they have not been investigated previously. The current study was undertaken to examine the effect of this factor further and to explore new ways of overcoming the resultant shortcomings. The authors now report on the immunodetection of a host of antigens in similarly preserved unstained serial paraffin slides obtained from three centers using a panel of eight antibodies. Staining of recently prepared sections from the authors' centers resulted in similar strong patterns in seven of eight antibodies, with one antibody demonstrating variable immunoreactivity. However, storage of unstained paraffin sections at room temperature resulted in a variable but progressive decrease in expression of several tissue antigens. Although the loss in antigenicity was proportional to the length of storage, the effect was reversible if super antibody concentrations were used. The authors conclude that recently prepared paraffin sections from centers with similar fixation protocols have similar immunoreactivity and are suitable for use in comparative multicenter studies. However, in view of the delays that may attend tissue transportation during these projects, the authors suggest that test systems should be checked for age-induced antigen degradation by incubating sections with higher antibody concentrations.

Antibodies↗
PubMed2004

Naltrexone depot for treatment of alcohol dependence: a multicenter, randomized, placebo-controlled clinical trial.

BACKGROUND: Studies of the efficacy of naltrexone for alcohol dependence have yielded variable findings, which may be due, in part, to variation in compliance with oral naltrexone. Efforts to improve naltrexone compliance have included the development of injectable, long-acting depot formulations. METHODS: We conducted a multicenter trial in 315 subjects who were randomly assigned to receive an intramuscular injection of a depot formulation containing naltrexone (n = 158) or a placebo formulation (n = 157) monthly for 3 months. All patients received five sessions of manual-guided motivational enhancement therapy during the 12 weeks of the study. The outcomes of interest were based on self-reported alcohol use and gamma-glutamyl transpeptidase level. Missing data or data from subjects who discontinued the study were conservatively treated as heavy-drinking days. RESULTS: Groups were comparable on pretreatment demographic and clinical measures. The medication was well tolerated; 73.7% of subjects received all injections. The time to the first heavy-drinking day, the percentage of subjects with no heavy drinking throughout the study, and gamma-glutamyl transpeptidase levels favored the naltrexone depot, although the effects did not reach statistical significance. There was a significant advantage for naltrexone depot treatment on the time to the first drinking day. Naltrexone depot subjects also had significantly fewer drinking days during treatment and a significantly greater abstinence rate than the placebo group (18% vs. 10%). CONCLUSIONS: This is the first multicenter study of a depot formulation of naltrexone for the treatment of alcohol dependence. Using a conservative intent-to-treat analysis, the study showed an advantage for the active medication. Further research with this formulation is warranted.

Adolescent↗
PubMed2005

A prospective, randomized, multicenter Food and Drug Administration investigational device exemption study of lumbar total disc replacement with the CHARITE artificial disc versus lumbar fusion: part II: evaluation of radiographic outcomes and correlation of surgical technique accuracy with clinical outcomes.

STUDY DESIGN: A prospective, randomized, multicenter, Food and Drug Administration-regulated, investigational device exemption clinical trial. OBJECTIVES: To compare the safety and effectiveness of lumbar total disc replacement (TDR) with the CHARITE artificial disc (DePuy Spine, Raynham, MA) to anterior lumbar interbody fusion for the treatment of single-level degenerative disc disease from L4-S1 unresponsive to nonoperative treatment. In addition, to evaluate the radiographic outcomes of lumbar artificial disc replacement at either L4-L5 or L5-S1 with the CHARITE artificial disc as compared to anterior lumbar interbody fusion with cylindrical cages and iliac crest bone graft; and to determine if a correlation exists between clinical outcomes and surgical accuracy of TDR placement within the disc space. SUMMARY OF BACKGROUND DATA: Prior investigators have reported excellent radiographic results with the CHARITE artificial disc for the treatment of lumbar degenerative disc disease. These encouraging results are the product of retrospective reviews without a control. Very few studies have reported on the segmental motion of an intervertebral level implanted with an artificial disc, and no studies have reported a correlation of radiographic and clinical outcomes. METHODS: A prospective, randomized, multicenter, US Food and Drug Administration, investigational device exemption study with 24-month follow-up was performed at 14 centers throughout the United States. A total of 304 subjects were randomized in a 2:1 ratio, with 205 in the investigational group (TDR with the CHARITE artificial disc) and 99 in the control group (anterior lumbar interbody fusion with BAK cages and iliac crest bone graft). A total of 71 TDR training cases were performed (up to 5 at each site) before randomization beginning at each site. Plain radiographs were analyzed for each subject in both groups regarding range of motion (ROM) in flexion/extension, restoration of disc space height, and subsidence. Prosthesis placement in the coronal and midsagittal planes was analyzed for the 276 patients with TDR. Correlations were performed between prosthesis placement and clinical outcomes. RESULTS: Patients in the investigational group had a 13.6% mean increase, and those in the control group an 82.5% decrease in mean flexion/extension ROM at 24 months postoperatively compared to baseline. Patients in the investigational group had significantly better restoration of disc height than the control group (P < 0.05). There was significantly less subsidence in the investigational group compared to the control group (P < 0.05). The surgical technical accuracy of CHARITE artificial disc placement was divided into 3 groups: I, ideal (83%); II, suboptimal (11%); and III, poor (6%), and correlated with clinical outcomes. The flexion/extension ROM and prosthesis function improved with the surgical technical accuracy of radiographic placement (P = 0.003). CONCLUSIONS: Preoperative ROM in flexion/extension was restored and maintained in patients receiving a TDR. TDR with the CHARITE artificial disc resulted in significantly better restoration of disc space height, and significantly less subsidence than anterior interbody fusion with BAK cages. Clinical outcomes and flexion/extension ROM correlated with surgical technical accuracy of CHARITE artificial disc placement. In the majority of cases, placement of the CHARITE artificial disc was ideal.

Adult↗
PubMed2003

A randomized, placebo controlled, multicenter study to evaluate the safety and efficacy of rofecoxib in the treatment of chronic nonbacterial prostatitis.

PURPOSE: We determine the effects of treatment with rofecoxib and placebo in patients with chronic prostatitis. MATERIALS AND METHODS: Patients diagnosed with chronic nonbacterial prostatitis were randomized to 6 weeks of 25 or 50 mg., rofecoxib or placebo in a double-blind multicenter study with a 1-week run in of placebo. End points included the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) (average pain score item 4 primary end point), and patient global assessment questions of pain, disease activity and response to therapy. RESULTS: A total of 161 patients were randomized in the study. The NIH-CPSI total, domain and pain scores significantly decreased from baseline in all groups and, although the mean scores numerically favored the rofecoxib groups, the difference was not significantly different among groups. There was a trend for the percentage of patients with a 25% (or 6 point) improvement in total score being superior on rofecoxib versus placebo with the difference being significantly different (p <0.05) for the 50 mg. rofecoxib group. Patient global assessment of pain, response to therapy and disease activity also favored rofecoxib over placebo (p <0.05, p = 0.07, p = 0.06, respectively). Of the patients 79% on 50 mg. rofecoxib versus 59% on placebo reported no or mild pain, and 56% of patients on 50 mg. rofecoxib versus 27% on placebo experienced significant improvement in quality of life (p <0.005). Rofecoxib was generally well tolerated. CONCLUSIONS: To our knowledge this study is the first to evaluate rofecoxib versus placebo in patients with prostatitis and the first large multicenter treatment study to use the NIH-CPSI. Subjective assessment with patient global questions may be more sensitive to change than the NIH-CPSI and, therefore, may be a better tool to use in future therapeutic trials. Although 6 weeks of rofecoxib treatment appear to benefit many men diagnosed with chronic prostatitis/chronic pelvic pain syndrome further studies are needed.

Adult↗
PubMed2004

Safety and efficacy of partial nephrectomy for all T1 tumors based on an international multicenter experience.

PURPOSE: We compared cancer specific survival of patients undergoing partial and radical nephrectomies for T1N0M0 renal tumors according to tumor size in a large multicenter series. MATERIALS AND METHODS: A retrospective analysis of 1454 patients undergoing partial or radical nephrectomy for T1N0M0 renal tumors from 7 international academic centers was performed. Data were obtained for each patient including TNM stage (determined according to the 2002 TNM criteria), tumor size, type of surgery (partial versus radical nephrectomy) and cancer specific survival. Recurrence events were recorded when available. RESULTS: Partial and radical nephrectomies were performed in 379 (26.1%) and 1075 (73.9%) cases, respectively. Mean followup +/- SD was 62.5 +/- 51.8 months. Recurrence data were available on 544 patients. There were no significant differences in local or distant recurrence rates between patients undergoing partial or radical nephrectomy for either T1a (p = 0.6) or T1b tumors (p = 0.5). For patients with T1a tumors, there was no significant difference in the rate of cancer specific deaths between the partial (314) and radical (499) nephrectomy groups (2.2% versus 2.6%, respectively, p = 0.8). For patients with T1b tumors there was also no significant difference in the rate of cancer specific deaths between patients undergoing partial (65) and patients undergoing radical (576) nephrectomy (6.2% versus 9%, respectively, p = 0.6). CONCLUSIONS: Partial nephrectomy is becoming the gold standard for renal tumors less than 4 cm but this treatment is much more controversial for larger T1 tumors. This large multicenter study suggests that it is safe to expand the indications of partial nephrectomy to include patients with T1N0M0 tumors up to 7 cm. However, careful patient selection remains necessary.

Carcinoma, Renal Cell↗
PubMed2004

Interim results from a national multicenter phase II trial of combination bacillus Calmette-Guerin plus interferon alfa-2b for superficial bladder cancer.

PURPOSE: Interim results are provided from a large multicenter trial of combination bacillus Calmette-Guerin (BCG) plus interferon (IFN) alfa-2b for BCG naive (BCG-N) and previous BCG failure (BCG-F) cases of superficial bladder cancer. MATERIALS AND METHODS: A total of 490 patients enrolled from May 1999 to May 2000 with a median of 24 months of followup were analyzed. The BCG-N group (259) was treated with a 6-week induction course of standard dose BCG plus 50 million units of IFN followed by 3, 3-week maintenance cycles of reduced dose BCG (1/3 to 1/10) plus 50 million units IFN at 3, 9 and 15 months after induction. The BCG-F group (231) was treated similarly except induction therapy began at a decreased (1/3 to 1/10) BCG dose. RESULTS: The simple tumor recurrence rates for BCG-N and BCG-F groups were 40% and 52%, and the Kaplan-Meier estimates for disease freedom at 24 months were 57% and 42%, respectively. Progression to muscle invasion occurred in 5% and 4.3% while metastasis occurred in 2.3% and 2.6%, respectively. In each group 3.9% of patients underwent cystectomy and 2 patients in each group died of bladder cancer. Serious adverse events occurred in 5.5% with infection related serious adverse events being less prevalent in the BCG-F group (2.6% vs 5.4%). Toxicity related dropout, treatment delay and/or further BCG dose reduction, and need for symptomatic drugs were similar. Moderate to severe local side effects during induction were higher in the BCG-F group (6.2% vs 16.9%) but equilibrated during maintenance therapy. Systemic reactions were rare. CONCLUSIONS: This multicenter trial provides a benchmark for the efficacy and safety of combination BCG and IFN as up front and salvage therapy. The incremental value of IFN cannot be determined from this study.

Aged↗
PubMed2005

A multicenter clinical trial on the use of (-5, -7) pro prostate specific antigen.

PURPOSE: The determination of pro prostate specific antigen (proPSA) forms has been suggested to be promising in prostate cancer diagnosis. In this multicenter trial we evaluated the diagnostic usefulness of (-5, -7) proPSA. MATERIALS AND METHODS: A total of 2,055 white men, including 1,046 with and 1,009 without prostate cancer, with total PSA (tPSA) between 0.28 and 81 ng/ml were retrospectively analyzed. Of these men 2,026 and 1,727 had tPSA less than 20 and less than 10 ng/ml, respectively. All subjects were untreated for prostatic disease and underwent multisector needle biopsy of the prostate. An Elecsys 2010 analyzer was used to determine tPSA, free PSA (fPSA) and (-5, -7) proPSA in the 2,055 serum samples. ROC analyses were performed to discriminate men with biopsy positive and negative results in the entire and in select tPSA ranges. RESULTS: In the select tPSA range 2 to 4 ng/ml the area under the ROC curve for proPSA (0.53) and proPSA/fPSA (0.59) was not significantly larger than that for tPSA (0.60) or the fPSA/tPSA (f/tPSA) ratio (0.64). In the tPSA range 4 to 10 ng/ml the area under the curve for the ratio proPSA/fPSA (0.67) was larger than for tPSA (0.53) but not larger than for f/tPSA (0.69). The f/tPSA ratio demonstrated the best discriminatory power in this tPSA range of 4 to 10 ng/ml. CONCLUSIONS: In this multicenter study no improvement in diagnostic accuracy was shown when comparing (-5, -7) proPSA and the corresponding ratios with tPSA or f/tPSA. Further studies using other proPSA forms or tumor associated proteins should be done.

Adult↗
PubMed2004

Results of a retrospective multicenter trial of the Viatorr expanded polytetrafluoroethylene-covered stent-graft for transjugular intrahepatic portosystemic shunt creation.

PURPOSE: To report the results of a multicenter experience with the Viatorr expanded polytetrafluoroethylene-covered stent-graft for transjugular intrahepatic portosystemic shunt (TIPS) creation in which patency and clinical outcome were evaluated. MATERIALS AND METHODS: One hundred consecutive patients with portal hypertension, with a mean age of 52 years (range, 22-86 years), underwent implantation of the Viatorr TIPS stent-graft at one of three hospital centers. The indications for TIPS creation were variceal bleeding (n = 81) and refractory ascites (n = 19). Twenty patients had Child-Pugh class A disease, 46 had class B disease, and 34 had class C disease. Eighty-seven patients underwent de novo TIPS placements, with 13 treated for recurrent TIPS stenosis. Sixty-two patients were available for follow-up portal venography and portosystemic pressure gradient (PSG) measurement commencing 6 months after Viatorr stent-graft placement. RESULTS: The technical success rate was 100%. TIPS creation resulted in an immediate decrease in mean PSG (+/-SD) from 21 mm Hg +/- 6 to 7 mm Hg +/- 3. Acute repeat intervention (within 30 days) was required for portal vein thrombosis (n = 1), continued bleeding (n = 3), and encephalopathy (n = 1). The all-cause 30-day mortality rate was 12%. Two patients developed acute severe refractory encephalopathy, which led to death in one case. New or worsening encephalopathy was identified in 14% of patients. The incidence of recurrent bleeding was 8%. The cumulative survival rate at 1 year was 65%. Sixty-two patients available for venographic follow-up had a mean PSG of 9 mm Hg +/- 5 at a mean interval of 343 days (range, 56-967 days). There were four stent-graft occlusions (6%) and seven hemodynamically significant stenoses (11%), four within the stent-graft and three in the non-stent-implanted hepatic vein. The primary patency rate at 1 year by Kaplan-Meier analysis was 84%. CONCLUSIONS: This retrospective multicenter experience with the Viatorr stent-graft confirms the preliminary findings of other investigators of good technical results and improved patency compared with bare stents. Early mortality and symptomatic recurrence rates are low by historical standards. The theoretical increase in TIPS-related encephalopathy was not demonstrated. Longer-term follow-up will be required to determine whether the additional cost of the Viatorr stent-graft will be offset by reduced surveillance and repeat intervention.

Adult↗
PubMed2006

Günther Tulip filter retrievability multicenter study including CT follow-up: final report.

PURPOSE: To evaluate the safety and effectiveness of retrieval of the Günther Tulip inferior vena cava (IVC) filter. MATERIALS AND METHODS: This was a nonrandomized, single-armed, multicenter prospective investigation. Patients at temporary high risk for pulmonary embolism (PE) or deep vein thrombosis (DVT) who did not require a permanent filter were eligible. Forty-one patients received 42 Günther Tulip filters: 22 men and 19 women with a mean age of 47.7 years. Indications for filter placement included prophylaxis, PE, and DVT. Three months after filter retrieval, contrast agent-enhanced computed tomography of the abdomen, jugular vein ultrasonography, and clinical follow-up were performed. RESULTS: The filter retrieval rate was 57% (23 of 41). Günther Tulip filters were removed at a mean of 11.1 days (range, 2-14 d). The technical and clinical success rates for filter retrieval were both 100%. One placement complication and two protocol deviations occurred. These patients were excluded in terms of retrieval-related outcomes. One case of PE occurred with a filter in place, and one filter migrated to the heart. There were no acute complications caused by filter retrieval. At 3-month follow-up, there was no recurrent PE, DVT, jugular vein occlusion, or IVC stenosis or occlusion. CONCLUSION: In this multicenter study, retrieval of the Günther Tulip filter was safe and without recurrent thromboembolic events or evidence of IVC or jugular vein damage at 3-month follow-up.

Adult↗
PubMed2004

Pylorus preserving pancreaticoduodenectomy versus standard Whipple procedure: a prospective, randomized, multicenter analysis of 170 patients with pancreatic and periampullary tumors.

OBJECTIVE: A prospective randomized multicenter study was performed to assess whether the results of pylorus-preserving pancreaticoduodenectomy (PPPD) equal those of the standard Whipple (SW) operation, especially with respect to duration of surgery, blood loss, hospital stay, delayed gastric emptying (DGE), and survival. SUMMARY BACKGROUND DATA: PPPD has been associated with a higher incidence of delayed gastric emptying, resulting in a prolonged period of postoperative nasogastric suctioning. Another criticism of the pylorus-preserving pancreaticoduodenectomy for patients with a malignancy is the radicalness of the resection. On the other hand, PPPD might be associated with a shorter operation time and less blood loss. METHODS: A prospective randomized multicenter study was performed in a nonselected series of 170 consecutive patients. All patients with suspicion of pancreatic or periampullary tumor were included and randomized for a SW or a PPPD resection. Data concerning patients' demographics, intraoperative and histologic findings, as well as postoperative mortality, morbidity, and follow-up up to 115 months after discharge, were analyzed. RESULTS: There were no significant differences noted in age, sex distribution, tumor localization, and staging. There were no differences in median blood loss and duration of operation between the 2 techniques. DGE was observed equally in the 2 groups. There was only a marginal difference in postoperative weight loss in favor of the standard Whipple procedure. Overall operative mortality was 5.3%. Tumor positive resection margins were found for 12 patients of the SW group and 19 patients of the PPPD group (P < 0.23). Long-term follow-up showed no significant statistical differences in survival between the 2 groups (P < 0.90). CONCLUSIONS: The SW and PPPD operations were associated with comparable operation time, blood loss, hospital stay, mortality, morbidity, and incidence of DGE. The overall long-term and disease-free survival was comparable in both groups. Both surgical procedures are equally effective for the treatment of pancreatic and periampullary carcinoma.

Adenocarcinoma↗
PubMed2006

Adhesive postoperative small bowel obstruction: incidence and risk factors of recurrence after surgical treatment: a multicenter prospective study.

OBJECTIVE: The aim of the present study was to determine the cumulative incidence and the risk factors of recurrence in patients operated on for an adhesive postoperative small bowel obstruction (SBO). SUMMARY BACKGROUND DATA: Postoperative intraperitoneal adhesions, or bands, resulting from any type of abdominal surgery, are the main cause of adhesive postoperative small bowel obstructions, which represent a life-long issue. Recurrences after operated adhesive postoperative SBO are a threatening potentiality for patients and a difficult problem facing any surgeon. Today the cumulative incidence and the risk factors of recurrence have been retrospectively reported but have never been prospectively evaluated in a multicenter study. METHODS: From January 1997 to January 2002, we enrolled 286 patients operated on for an adhesive postoperative SBO in a prospective multicenter trial. A systematic follow-up was carried out and ended in April 2003. Studied factors for recurrent adhesive postoperative SBO were as follows: age, gender, ASA status, number and sites of previous operations, previous operation for adhesive postoperative SBO, elapsed time from the latest operation, surgical approach, number and type of obstructive structures, site and mechanism of obstruction, final operations, and postoperative surgical and medical complications. They were analyzed using Kaplan-Meier method. A Cox regression model was used to determine the independent risk factor of recurrence. RESULTS: The median follow-up was 41 months (range, 1-75 months). The cumulative incidence of overall recurrence was 15.9%, and for surgically managed recurrence 5.8%. In multivariate analysis, the risk factors for the overall recurrences were age <40 years (hazard ratio [HR], 2.97; confidence interval [CI], 1.48-5.94), adhesion or matted adhesion (HR, 3.79; CI, 1.84-7.78) and, for the surgically managed: adhesions or matted adhesions (HR, 3.64; CI, 1.12-11.84), and postoperative surgical complications (HR, 5.63; CI, 1.73-18.28). CONCLUSION: Operated adhesive postoperative SBO is a clinical entity with a high recurrence rate and specific risk factors of recurrences. Thus, the patients operated on for adhesive postoperative SBO may be candidates for the preventive use of anti-adhesion agents, particularly when a risk factor of recurrence is present.

Adolescent↗
PubMed2005

Logistics and transplant coordination activity in the GRAGIL Swiss-French multicenter network of islet transplantation.

BACKGROUND: Since the Edmonton trial in 2000, increasing numbers of transplant centers have been implementing islet transplantation programs. Some institutions have elected to associate in multicenter networks, such as the Swiss-French GRAGIL (Groupe Rhin-Rhône-Alpes-Genève pour la Transplantation d'Ilots de Langerhans) consortium. METHODS: All pancreata offers to the University of Geneva Cell Isolation and Transplantation Center from within the network in 2002 and 2003 were reviewed. Islet preparations were attributed to the most suitable recipient on a centrally managed waiting list. All shipments were performed by ambulance in less than 5 hr. RESULTS: Over the period of study, 260 pancreata were offered, from a total of 1,304 cadaveric donors in the four allocation regions (20%). Fifty-two patients were on the waiting list at any time during this 2-year period. The percentage of organs offered varied in the range of 0.5% to 42%, depending on region of origin, with a correlation with number of patients on the waiting list in each region. Of these, 104 (40%) were accepted for processing. Ninety-two pancreata were actually processed, resulting in 42 islet preparations being transplanted. The number of international equivalents of transplanted preparations was 378,500+/-16,000 versus 165,400+/-15,400 (P<0.0001) for nontransplanted preparations. Total cold ischemia time was 6+/-0.3 hr for transplanted preparations versus 6.7+/-0.4 hr for nontransplanted preparations (not significant). CONCLUSIONS.: A high rate of pancreas offers, successful isolation, and islet transplantation can be achieved in multicenter networks such as GRAGIL. Such an approach can expand both the donor pool and the recipient population.

Adult↗
PubMed2006

The emergency department triage of community-acquired pneumonia project data and documentation systems: a model for multicenter clinical trials.

Multicenter clinical trials are complex undertakings that require significant resources to ensure efficient, high quality research. This paper describes the goals, design, and implementation of a multicenter clinical trial database management system to support this aim. A large number of study sites or patients, and the goal of automatically generating large portions of data management infrastructure from common metadata, motivated the development of the system. This paper also describes extensions for a generalized project documentation system, and discusses plans for further extensions and improvements based on observed strengths, limitations, and anticipated technological change.

Community-Acquired Infections↗
PubMed1999

Adjusted regression trend test for a multicenter clinical trial.

Studies using a series of increasing doses of a compound, including a zero dose control, are often conducted to study the effect of the compound on the response of interest. For a one-way design, Tukey et al. (1985, Biometrics 41, 295-301) suggested assessing trend by examining the slopes of regression lines under arithmetic, ordinal, and arithmetic-logarithmic dose scalings. They reported the smallest p-value for the three significance tests on the three slopes for safety assessments. Capizzi et al. (1992, Biometrical Journal 34, 275-289) suggested an adjusted trend test, which adjusts the p-value using a trivariate t-distribution, the joint distribution of the three slope estimators. In this paper, we propose an adjusted regression trend test suitable for two-way designs, particularly for multicenter clinical trials. In a step-down fashion, the proposed trend test can be applied to a multicenter clinical trial to compare each dose with the control. This sequential procedure is a closed testing procedure for a trend alternative. Therefore, it adjusts p-values and maintains experimentwise error rate. Simulation results show that the step-down trend test is overall more powerful than a step-down least significant difference test.

Aged↗
PubMed2005

Inflow stenosis in arteriovenous fistulas and grafts: a multicenter, prospective study.

BACKGROUND: Traditionally, arteriovenous hemodialysis access inflow stenosis has been reported to occur infrequently (0% to 4%). In contrast, recent reports have suggested a significantly higher incidence (14% to 42%). Interpretation of these studies has been complicated by the presence of one or more confounding factors such as retrospective study design, small sample size, arteriovenous fistulas grouped with grafts to determine the incidence of inflow stenosis, inclusion of fistulas that had failed primarily, failure to provide adequate definition of inflow stenosis, and the technique of retrograde angiography. This is a report of a prospective, multicenter study to examine the incidence of inflow stenosis separately in arteriovenous fistulas and grafts. METHODS: Patients were referred to interventional nephrology either for percutaneous balloon angioplasty or thrombectomy procedures. Angiography to evaluate access inflow (arterial anastomosis and adjacent vascular structures) was performed in all cases. This was accomplished by retrograde angiography using either manual occlusion of the venous side and/or advancing a diagnostic catheter across the arterial anastomosis. Multiple images using digital subtraction angiography were recorded in multiple planes. An inflow stenosis was defined as stenosis within the arterial system, artery-graft anastomosis (graft cases), artery-vein anastomosis (fistula cases) and juxta-anastomotic region (the first 2 cm downstream from the arterial anastomosis). Vascular stenosis was defined as >/=50% reduction in luminal diameter judged by comparison with either the adjacent vessel or graft. A standardized definition for anastomotic stenosis was applied. RESULTS: Two hundred and twenty three consecutive procedures (grafts, 122; fistulas, 101) were performed in 158 patients. Inflow stenosis occurred in 36/122 (29%) in graft cases. All had a coexisting stenosis on the venous side. In fistula cases, 41/101 (40%) had inflow stenosis. Of these, 22 (54%) had a coexisting lesion on the venous side. Overall, inflow stenosis occurred in 77/223 procedures (35%). CONCLUSION: This prospective, multicenter study demonstrates that access inflow stenosis occurs in one third of the cases referred to interventional facilities with clinical evidence of venous stenosis or thrombosis. This is much higher than has been traditionally reported.

Adult↗