[Is the general practice laboratory medically and economically valuable?]. / Ist das Praxislabor medizinisch und wirtschaftlich sinnvoll?

UNLABELLED: Between 1998 and 2000 we evaluated the office-based laboratory activities of general practitioners. The aim was to clarify whether there is a medical and economic benefit of these activities. METHODS: The study was performed in four parts: I. A cross-sectional study with a random sample of general practitioners of the German and French speaking part of Switzerland. II. A prospective evaluation of the office-based laboratory activities of 56 GP's. III. A cross-sectional study of the preference of 837 patients in 52 of GP's offices. IV. A consensus panel with nine experts using the RAND method. RESULTS: 1999 there were 55.4 Million laboratory tests ordered by GP's (excl. pediaters) of which 78.9% were analysed in the office-based laboratory. The probability of a second visit is reduced by 60%, if all of the tests could be performed in the office-based laboratory. 85% of the patients appreciate the possibility to discuss the test results within the same consulation. In the consensus panel, 43 tests were proposed of which only bicarbonate, chloride and urea were assessed as not useful for the office based laboratory. CONCLUSION: The office-based laboratory is a well embodied institution in Switzerland. It's predominant advantage is the possibility of point of care testing. It allows a quick management of the patient and avoids unnecessary second consultations.

[Medical economy--a new challenge for physicians]. / Medizinische Okonomie--eine Herausforderung für die Arzteschaft.

What is medical economics? It stands on three important columns: (1) economic analysis (2) policy and decision analysis and (3) outcomes research. Economic evaluations consist always of two components: resource utilization and outcomes. Cost-benefit-analysis requires that the outcome is expressed in monetary terms, in cost-effectiveness-analysis outcomes are expressed in non-monetary terms and cost-utility analysis requires QUALY's (quality adjusted life years) as output. Why do we need medical economics? On one hand we wish to allocate the restricted means as fairly as possible. On the other hand, we have new but more expensive methods and preventive measures. Medical economics can contribute to this situation: through a systematic assessment of the efficiency of the different methods. The potential of cost savings and arguments for new and more expensive methods can be developed, if they are advantageous in the context of the prevention of disease progression or sequelae. The aim of the department is to promote research, to develop the basis for decision-makers, to give lectures and seminars, to support other researchers in the area of medical economics and to take up and cultivate contacts with different actors of health care systems.

Variation in antimicrobial utilization for febrile neutropenia in cancer patients. The CEMIC Study Group. Club d'Etudes des Maladies Infectieuses en Cancer.

BACKGROUND: No previous study has compared hospitals with respect to the variation of antimicrobial utilization (AU) for cancer patients with febrile neutropenia (FNE). PATIENTS AND METHODS: We conducted an observational cohort study, carried out in 18 tertiary care centers across nine countries, in order to describe AU patterns for cancer patients with FNE and to evaluate whether prescription was appropriate. RESULTS: A total of 148 patients was exposed to 483 antimicrobial agents and 318 therapeutic courses, corresponding to 1,766 antimicrobial exposure-days. The most frequently used initial treatment consisted of a combination of a broad-spectrum beta-lactam agent and an aminoglycoside (50%). The extent of initial monotherapy varied between 5% in German and 30% in French centers. Glycopeptides, fluconazole and acyclovir were incorporated into initial empiric therapy in 21,13, and nine instances, respectively. The French centers prescribed the largest number of antimicrobial courses per FNE (mean 2.5 +/-1.5), whereas the center with the highest antimicrobial exposure density was observed in the USA (2.8 exposure-days per 1 FNE-day). AU was judged to be inappropriate by at least one criterion in 59 patients (40%). CONCLUSION: This pilot study revealed important variation in AU intensity and prescription preferences in FNE patients and may help to develop appropriate strategies to improve antimicrobial therapy for this patient population.

Resource implications of febrile neutropenia in cancer patients. An international collaborative study.

No previous study has compared countries with respect to differences in clinical practice and resource use of cancer patients with febrile neutropenic episodes (FNE). The purpose of this international, cross-sectional pilot study conducted in tertiary care centers across Europe, Brazil and Australia was to evaluate the resource use attributable to febrile neutropenia in different countries. A total of 17 centers from eight countries provided 128 patients. The leading malignant disorders were hematological malignancies (n = 47), lymphomas (n = 27), and breast cancer (n = 26). The median length of duration of FNE was 4 days (interquartile range, 3-8). The incidence density of antimicrobial exposure was 4.691 days of antimicrobial therapy per 1,000 days of FNE. There were 23 patients who received a total of 280 days of G-CSF therapy. On average, 5 (+/-5.4) blood samples per patient were drawn and cultured. The most common diagnostic radiographic test was the chest X-ray, with a total of 224 such examinations performed in 82 patients. We conducted an international cross-sectional study on resource implications of febrile neutropenia in cancer patients. The records of the febrile neutropenic patients included in this study reflect clinical practice in a heterogeneous, international patient population, treated with modern supportive care and early empiric antibiotics by clinicians at different levels of expertise.

Chronic respiratory alkalosis. The effect of sustained hyperventilation on renal regulation of acid-base equilibrium.

BACKGROUND: In normal subjects, chronic hyperventilation lowers plasma bicarbonate concentration, primarily by inhibiting the urinary excretion of net acid. The quantitative relation between reduced arterial carbon dioxide tension (PaCO2) and the plasma bicarbonate concentration in the chronic steady state has not been studied in humans, however, and the laboratory criteria for the diagnosis of chronic respiratory alkalosis therefore remain undefined. We wished to provide such reference data for clinical use. Moreover, because chronic hyperventilation paradoxically lowers blood pH still further in dogs with metabolic acidosis, we desired to study the effect of chronic hypocapnia on the plasma bicarbonate concentration (and blood pH) in normal human subjects in whom acidosis had been induced with ammonium chloride. METHODS: Under metabolic-balance conditions, we used altitude-induced hypobaric hypoxia to produce chronic hypocapnia in nine normal young men, five of whom received ammonium chloride daily to cause metabolic acidosis (the mean [+/- SE] steady-state plasma bicarbonate level in these five was 12.0 +/- 0.5 mmol per liter). RESULTS: For each decrease of 1 mm Hg (0.13 kPa) in the PaCO2, the plasma bicarbonate concentration decreased by 0.41 mmol per liter in the subjects who started with a normal plasma bicarbonate concentration and by 0.42 mmol per liter in the subjects with acidosis. In contrast to the findings in previous studies of dogs, hypocapnia increased blood pH similarly in both groups; the blood hydrogen ion concentration decreased by about 0.4 nmol per liter for every decrease of 1 mm Hg (0.13 kPa) in PaCO2. CONCLUSIONS: These results provide reference data for the diagnosis of chronic respiratory alkalosis in humans. Although chronic hypocapnia decreased plasma bicarbonate levels similarly in normal subjects with acidosis and without acidosis, the percent reduction in PaCO2 was always greater than the corresponding percent reduction in the plasma bicarbonate concentration. Therefore, as was not true of the response in dogs, the subjects' blood pH always increased with hyperventilation, regardless of the initial plasma bicarbonate concentration.