European interlaboratory comparison of breath 13CO2 analysis.
The BIOMED I programme Stable Isotopes in Gastroenterology and Nutrition (SIGN) has focused upon evaluation and standardisation of stable isotope breath tests using 13C labelled substrates. The programme dealt with comparison of 13C substrates, test meals, test conditions, analysis techniques, and calculation procedures. Analytical techniques applied for 13CO2 analysis were evaluated by taking an inventory of instrumentation, calibration protocols, and analysis procedures. Two ring tests were initiated measuring 13C abundances of carbonate materials. Evaluating the data it was found that seven different models of isotope ratio mass spectrometers (IRMS) were used by the participants applying both the dual inlet system and the continuous flow configuration. Eight different brands of certified 13C reference materials were used with a 13C abundance varying from delta 13CPDB -37.2 to +2.0/1000. CO2 was liberated from certified material by three techniques and different working standards were used varying from -47.4 to +0.4/1000 in their delta 13CPDB value. The standard deviations (SDs) found for all measurements by all participants were 0.25/1000 and 0.50/1000 for two carbonates used in the ring tests. The individual variation for the single participants varied from 0.02 /1000 (dual inlet system) to 0.14/1000 (continuous flow system). The measurement of the difference between two carbonates showed a SD of 0.33/1000 calculated for all participants. Internal precision of IRMS as indicated by the specifications of the different instrument suppliers is < 0.3/1000 for continuous flow systems. In this respect it can be concluded that all participants are working well within the instrument specifications even including sample preparation. Increased overall interlaboratory variation is therefore likely to be due to non-instrumental conditions. It is possible that consistent differences in sample handling leading to isotope fractionation are the causes for interlaboratory variation. Breath analysis does not require sample preparation. As such, interlaboratory variation will be less than observed for the carbonate samples and within the range indicated as internal precision for continuous flow instruments. From this it is concluded that pure analytical interlaboratory variation is acceptable despite the many differences in instrumentation and analytical protocols. Coordinated metabolic studies appear possible, in which different European laboratories perform 13CO2 analysis. Evaluation of compatibility of the analytical systems remains advisable, however. (+info)
Management of coeliac disease: a changing diagnostic approach but what value in follow up?
OBJECTIVE: To assess the management of patients with coeliac disease in relation to a change in diagnostic method from jejunal suction biopsy to endoscopic biopsy. DESIGN: 16 item questionnaire survey of consultant members of the British Society of Gastroenterology. SUBJECTS: 359 consultant physician and gastroenterologist members of the society. MAIN MEASURES: Type of routine biopsy; repeat biopsy after gluten withdrawal; gluten rechallenge; follow up measurements; screening for malignancy; and methods of follow up, including special clinics. RESULTS: 270(70%) members replied; 216(80%) diagnosed coeliac disease routinely by endoscopic duodenal biopsy, 30(11%) by jejunal capsule biopsy, and the remainder by either method. Only 156(58%) repeated the biopsy after gluten withdrawal, though more did so for duodenal than jejunal biopsies (134/216, 62% v 13/30, 43%; p < 0.02). Follow up biopsies featured more duodenal than jejunal biopsies (133/156, 82% v 23/156, 15%; p < 0.02). Regular follow up included assessments of weight (259, 96%) and full blood count (238, 88%) but limited assessment of serum B-12 and folate (120, 44%) and calcium (105, 39%) concentrations. Routine screening for malignancy is not performed, and there are few specialist clinics. 171(63%) respondents thought that patients should be followed up by a hospital specialist and 58(21%) by family doctors. CONCLUSIONS: The practice of diagnosing coeliac disease varies appreciably from that in many standard texts. Many patients could be effectively cared for by their family doctor. IMPLICATIONS: The British Society of Gastroenterology should support such management by family doctors by providing clear guidelines for them. (+info)
Feasibility of monitoring patient based health outcomes in a routine hospital setting.
OBJECTIVE: To assess the feasibility of monitoring health outcomes in a routine hospital setting and the value of feedback of outcomes data to clinicians by using the SF 36 health survey questionnaire. DESIGN: Administration of the questionnaire at baseline and three months, with analysis and interpretation of health status data after adjustments for sociodemographic variables and in conjunction with clinical data. Exploration of usefulness of outcomes data to clinicians through feedback discussion sessions and by an evaluation questionnaire. SETTING: One gastroenterology outpatient department in Aberdeen Royal Hospitals Trust, Scotland. PATIENTS: All (573) patients attending the department during one month (April 1993). MAIN MEASURES: Ability to obtain patient based outcomes data and requisite clinical information and feed it back to the clinicians in a useful and accessible form. RESULTS: Questionnaires were completed by 542 (95%) patients at baseline and 450 (87%) patients at follow up. Baseline health status data and health outcomes data for the eight different aspects of health were analysed for individual patients, key groups of patients, and the total recruited patient population. Significant differences were shown between patients and the general population and between different groups of patients, and in health status over time. After adjustment for differences in sociodemography and main diagnosis patients with particularly poor scores were identified and discussed. Clinicians judged that this type of assessment could be useful for individual patients if the results were available at the time of consultation or for a well defined group of patients if used as part of a clinical trial. CONCLUSIONS: Monitoring routine outcomes is feasible and instruments to achieve this, such as the SF 36 questionnaire, have potential value in an outpatient setting. IMPLICATIONS: If data on outcomes are to provide a basis for clinical and managerial decision making, information systems will be required to collect, analyse, interpret, and feed it back regularly and in good time. (+info)
Gastroenterology research in the United Kingdom: funding sources and impact.
AIMS: To determine the sources of founding for UK gastroenterology research papers and the relative impact of papers funded by different groups and of unfunded ones. METHODS: UK gastroenterology papers from 1988-94 were selectively retrieved from the Science Citation Index by means of a specially constructed filter based on their title keywords and journal names. They were looked up in libraries to determine their funding sources and these, together with their numbers of authors, numbers of addresses, and research category (clinical/basic) were considered as input parameters to the research. Output parameters analysed were mean journal impact category, citation counts by papers, and the frequency of citation by a US patient. RESULTS: Gastroenterology papers comprise about 7% of all UK biomedical research and 46% of them have no acknowledged funding source. One quarter of the papers acknowledged government support, and a similar fraction a private, non-profit source; 11% were funded by the pharmaceutical industry. The papers acknowledging funding had significantly more impact than the others on all three measures. The citing patents had six times more UK inventors than the average for all US Patent and Trademark Office patents in the relevant classes and were mostly generic in application. CONCLUSION: The variation in impact of papers funded by different sources can mostly be explained by a simple model based on the input factors (numbers of funding bodies, numbers of authors, numbers of addresses, and research type). The national science base in gastroenterology is important for the underpinning of UK invented patents citing to it. (+info)
Gastrointestinal surgical workload in the DGH and the upper gastrointestinal surgeon.
Workload implications of upper gastrointestinal (UGI) subspecialisation within the district general hospital (DGH) have been assessed by prospective data collection over a 12-month period in a DGH with six general surgeons serving a population of 320,000. The single UGI surgeon (UGIS) performed all ten oesophageal resections, ten of 11 gastric resections for malignancy and all eight pancreatic operations. He also performed 91 of the 182 cholecystectomies, 164 of the 250 endoscopic retrograde cholangiopancreatograms (ERCP) and all endoscopic procedures for the palliation of unresected oesophageal tumours. The UGIS was responsible for the management of all patients with severe pancreatitis, yet he also performed 51 colorectal resections over the 12-month period. Successful management of severely ill patients with upper GI disease requires consultant supervision on a day-to-day basis. If such UGI disease is to be managed in the DGH, two surgeons with UGI experience will be required if high quality care and reasonable working conditions are to be achieved. Such UGIS will continue to perform some colorectal surgery. (+info)
Management of uninvestigated and functional dyspepsia: a Working Party report for the World Congresses of Gastroenterology 1998.
BACKGROUND: The management of dyspepsia is controversial. METHODS: An international Working Party was convened in 1998 to review management strategies for dyspepsia and functional dyspepsia, based on a review of the literature and best clinical practice. RESULTS: Dyspepsia, defined as pain or discomfort centred in the upper abdomen, can be managed with reassurance and over-the-counter therapy if its duration is less than 4 weeks on initial presentation. For patients with chronic symptoms, clinical evaluation depends on alarm features including patient age. The age cut off selected should depend on the age specific incidence when gastric cancer begins to increase, but in Western nations 50 years is generally an acceptable age threshold. In younger patients without alarm features, Helicobacter pylori test and treatment is the approach recommended because of its value in eliminating the peptic ulcer disease diathesis. If, after eradication of H. pylori, symptoms either are not relieved or rapidly recur, then an empirical trial of therapy is recommended. Similarly, in H. pylori-negative patients without alarm features, an empirical trial (with antisecretory or prokinetic therapy depending on the predominant symptom) for up to 8 weeks is recommended. If drugs fail, endoscopy should be considered because of its reassurance value although the yield will be low. In older patients or those with alarm features, prompt endoscopy is recommended. If endoscopy is non-diagnostic, gastric biopsies are recommended to document H. pylori status unless already known. While treatment of H. pylori is unlikely to relieve the symptoms of functional dyspepsia, the long-term benefits probably outweigh the risks and treatment can be considered on a case-by-case basis. In H. pylori-negative patients with documented functional dyspepsia, antisecretory or prokinetic therapy, depending on the predominant symptom, is reasonable, assuming reassurance and explanation are insufficient, unless patients have already failed this approach. Other treatment options include antidepressants, antispasmodics, visceral analgesics such as serotonin type 3 receptor antagonists, and behavioural or psychotherapy although these are all of uncertain efficacy. Long-term drug treatment in functional dyspepsia should be avoided; intermittent short courses of treatment as needed is preferred. CONCLUSION: The management of dyspepsia recommended is based on current best evidence but must be tailored to local factors such as practice setting, the background prevalence of H. pylori and structural disease, and costs. (+info)
National trends in gastroesophageal reflux surgery.
OBJECTIVES: To assess the surgical technique and the frequency of different types of antireflux surgery used in Canada after the introduction of laparoscopic antireflux surgery. DESIGN: Gastroesophageal reflux (GER) surgery and population data in fiscal years 1992 through 1996. were accessed through the Canadian Institute of Health Information, provincial health ministries, MED ECHO and Statistics Canada databases. Data were also analysed by province and nationally for type of surgery (e.g., open abdominal, thoracic, thoracoscopic and laparoscopic). RESULTS: National data showed a slight increase in GER surgery in the last 5 years. Laparoscopic surgery increased 2.8 fold in 1993 and 1.6 fold in 1995 over the previous years. Open abdominal cases decreased 1.1 fold from 1992 to 1996. Thoracic cases remained essentially unchanged. Provincial and regional disparities in procedures per 100,000 population exist (Ontario 7.1 versus Nova Scotia 20.7). Areas in which little or no laparoscopic surgery was done had an average increase of 3%, whereas areas in which laparoscopic surgery was done had an average increase of 16% in GER surgery during the course of the study. In provinces west of Quebec (with the exception of Manitoba) more than 50% of GER surgery is laparoscopic; in areas east of Ontario less than 25% of GER surgery is performed laparoscopically. Five provinces (Manitoba, Quebec, Nova Scotia, Prince Edward Island and Newfoundland) performed significantly fewer laparoscopic procedures than the national average. CONCLUSIONS: The frequency of GER surgery is increasing modestly in Canada and is performed most often by the open abdominal route. Regional disparities in open and laparoscopic techniques are apparent. Laparoscopic surgery for GER is increasing rapidly and accounts for the decrease in open GER surgery. (+info)
Differences between generalists and specialists in characteristics of patients receiving gastrointestinal procedures.
BACKGROUND: As a result of market forces and maturing technology, generalists are currently providing services, such as colonoscopy, that in the past were deemed the realm of specialists. OBJECTIVE: To determine whether there were differences in patient characteristics, procedure complexity, and clinical indications when gastrointestinal endoscopic procedures were provided by generalists versus specialists. DESIGN: Retrospective cohort study. PATIENTS: A random 5% sample of aged Medicare beneficiaries who underwent rigid and flexible sigmoidoscopy, colonoscopy, and esophagogastroduodenoscopy (EGD) performed by specialists (gastroenterologists, general surgeons, and colorectal surgeons) or generalists (general practitioners, family practitioners, and general internists). MEASUREMENTS: Characteristics of patients, indications for the procedure, procedural complexity, and place of service were compared between generalists and specialists using descriptive statistics and logistic regression. MAIN RESULTS: Our sample population had 167,347 gastrointestinal endoscopies. Generalists performed 7.7% of the 57, 221 colonoscopies, 8.7% of the 62,469 EGDs, 42.7% of the 38,261 flexible sigmoidoscopies, and 35.2% of the 9,396 rigid sigmoidoscopies. Age and gender of patients were similar between generalists and specialists, but white patients were more likely to receive complex endoscopy from specialists. After adjusting for patient differences in age, race, and gender, generalists were more likely to have provided a simple diagnostic procedure (odds ratio [OR] 4.2; 95% confidence interval [95% CI] 4.0, 4.4), perform the procedure for examination and screening purposes (OR 4.9; 95% CI, 4. 3 to 5.6), and provide these procedures in rural areas (OR 1.5; 95% CI 1.4 to 1.6). CONCLUSIONS: Although generalists perform the full spectrum of gastrointestinal endoscopies, their procedures are often of lower complexity and less likely to have been performed for investigating severe morbidities. (+info)