Using Spontaneous Emission of a Qubit as a Resource for Feedback Control.

Persistent control of a transmon qubit is performed by a feedback protocol based on continuous heterodyne measurement of its fluorescence. By driving the qubit and cavity with microwave signals whose amplitudes depend linearly on the instantaneous values of the quadratures of the measured fluorescence field, we show that it is possible to stabilize permanently the qubit in any targeted state. Using a Josephson mixer as a phase-preserving amplifier, it was possible to reach a total measurement efficiency η=35%, leading to a maximum of 59% of excitation and 44% of coherence for the stabilized states. The experiment demonstrates multiple-input multiple-output analog Markovian feedback in the quantum regime.

An objective method for bed capacity planning in a hospital department - a comparison with target ratio methods.

OBJECTIVES: To propose an objective approach in order to determine the number of beds required for a hospital department by considering how recruitment fluctuates over time. To compare this approach with classical bed capacity planning techniques. METHODS: A simulated data-based evaluation of the impact that the variability in hospital department activity produces upon the performance of methods used for determining the number of beds required. The evaluation criteria included productive efficiency measured by the bed occupancy rate, accessibility measured by the transfer rate of patients due to lack of available beds and a proxy of clinical effectiveness, by the proportion of days during which there is no possibility for unscheduled admission. RESULTS: When the variability of the number of daily patients increases, the Target Occupancy Rate favors productive efficiency at the expense of accessibility and proxy clinical effectiveness. On the contrary, when the variability of the department activity is marginal, the Target Activity Rate penalizes the proxy of clinical effectiveness, and the Target Occupancy Rate underoptimizes productive efficiency. The method we propose led to a superior performance in terms of accessibility and proxy of clinical effectiveness at the expense of productive efficiency. Such a situation is suitable for intensive care units. In the case of other departments, a weighting procedure should be used to improve productive efficiency. CONCLUSIONS: This approach could be considered as the first step of a family of methods for quantitative healthcare planning.

[Central-venous-catheter-related bacteremia in neonatalogy]. / Bactériémies nosocomiales sur cathéters veineux centraux en néonatologie.

OBJECTIVE: The aim of this retrospective study was to identify the risk factors for catheter-associated bloodstream infection (CABSI) in neonates. METHOD AND RESULTS: Fifteen episodes of CABSI occurred in 108 central catheters over a period of one year (2002). The univariate analysis risk factors were birth weight (1.064 vs 1.413 g; P<0.001), gestation age (28 vs 31 weeks; P<0.001), blood transfusion (8/15 vs 3/34; P<0.01), corticosteroids (7/15 vs 3/34; P<0.01), nasal CPAP duration (13.6 vs 2 days; P<0.01). Nasal CPAP duration was the only risk factor independently associated with CASBI (OR=1.2, 95% confidence interval=1.09-1.5) in the multivariate logistic regression analysis. CONCLUSIONS: The risk of infection associated with low birth weight is multifactorial suggesting that host-related factors are important. Prevention remains difficult and a policy of strict aseptic catheter care must be promoted.

A simple method to optimize hospital beds capacity.

OBJECTIVE: The number of acute hospital beds is determined by health authorities using methods based on ratios and/or target bed occupancy rates. These methods fail to consider the variability in hospitalization demands over time. On the other hand, the implementation of sophisticated models requires the decision concerning the number of beds to be made by an expert. Our aim is to develop a new method that is as simple to use as the ratio method while minimizing the roundabout approaches of these methods. METHOD: A score was constructed with three parameters: number of transfers due to lack of space, number of days with no possibility for S unscheduled admissions and number of days with at least a threshold of U unoccupied beds. The optimal number of beds is the number for which both the mean and the standard deviation of the score reach their minimum. We applied this method to two internal medicine departments and one urological surgery department and we compared the solutions proposed by this method with those put forward by the ratio method. RESULTS: The solutions proposed by this method were intermediate to those calculated by the local and national length of Stays ratio methods. Simulating an unusual increase in admission requests had no consequence on the bed number selected, indicating that the method was robust. CONCLUSION: Our tool represents a real alternative to the ratio methods. A software has been developed and is now available for use.

A universal method for determining intensive care unit bed requirements.

OBJECTIVE: Most methods used to estimate ICU bed needs rely either on simple formulas that do not consider the actual needs of the population or on simulations that are too specific to be applicable to all hospitals. We sought to develop a universally applicable nonparametric method. DESIGN AND SETTING: For each day, the number of immediate patient transfers to other ICUs because of a full unit and the number of patients treated in the ICU were collected. The number of beds needed was selected according to the minimization of both the mean and the variance of three parameters (accessibility, safety, and efficiency). This method was applied to the ICU of a general hospital. Robustness of the model was assessed using outliers. MAIN RESULTS: During the 5-month study period, 215 ICU stays were collected. The method selected a ten-bed model whereas length-of-stay ratio and case-mix methods selected a twelve- and height-bed models respectively. An unusual increase in admission requests had no consequence on the bed number selected, indicating that the method was robust. None of the parameters were dependent on specific ICU characteristics, establishing that this method is applicable to any type of hospital ward. CONCLUSION: Our model is reliable for determining the number of beds needed in any type of ICU and can be used by all ICU managers. The software is available.

[Cause of non-pertinent hospital stays: interobserver concordance using the French version of the Appropriateness Evaluation Protocol]. / Etude de la concordance inter-observateurs des raisons de non-pertinence des journées d'hospitalisation identifiée par la version française de l'Appropriateness Evaluation Protocol (2e partie).

BACKGROUND: The modified French version of the Appropriateness Evaluation Protocol (AEPf) has been validated. Inappropriate days according to simple medical and technical criteria are identified with this tool. The aim of this study is to highlight the interest of investigating the reasons for inappropriate days and to assess the inter-observers reliability of the questionnaire developed for this purpose. METHODS: This questionnaire collects on one hand the needs of patients - distinguishing health care and accommodation needs - and on the other hand the reasons for inappropriate hospital days. The data were collected from January to September 1998 in nine voluntary medical and surgical departments. For each day of study randomly selected, each inappropriate hospital day according to AEPf has been included. Data were collected by two health professionals (a nurse and a physician), using a concurrent design. RESULTS: The reliability of the over-ride option of the appropriateness assessment of the 345 hospital days was good (overall Kappa coefficient: 0.66; 95% CI: 0.55-0.78). The comparison of the two expert judgments on health care needs fulfilled during the hospital day was acceptable; the Kappa coefficient was 0.62 (95% CI: 0.52-0.72). The reliability of expert assessment on patient accommodation needs (home, housing facilities or hospital) was good (Kappa coefficient: 0.67; 95% CI: 0.60-0.75). When hospital was not the accommodation the most adapted for patient, the reliability of the reasons for inappropriate days was high (Kappa coefficient: 0.75; 95% CI: 0.61-0.80). Kappa coefficients were different between hospitals, indicating a center effect. CONCLUSION: This instrument has been found to be reliable and should be used in complement of the first part of the AEPf which assess the prevalence of inappropriate days. It might help to detect dysfunctions within or outside the hospital and thus be used for evaluation or planning of health care.

[Vitamin B12 deficiency in geriatrics]. / Vitamin B12-Mangel in der Geriatrie.

Cobalamin deficiency increases with advancing age. The cut-off point of serum concentration should be raised, because many elderly people with "normal" serum vitamin B12 concentrations are metabolically deficient in cobalamin. The measurement of the metabolites homocysteine and/or methylmalonic acid is recommended. Cobalamin deficiency may result in a variety of atypical symptoms. Hematological changes typical of megaloblastic anemia are absent in a majority of patients with neuropsychiatric disorders. Generally underlying pernicious anemia is not the main cause of cobalamin deficiency in the elderly. Protein-bound cobalamin malabsorption due to atrophic gastritis with hypo- or achlorhydria is a common cause of cobalamin deficiency in elderly people. An important manifestation of cobalamin deficiency is cognitive impairment. Much controversy exists on the subject of the association of dementia of the Alzheimer type with cobalamin deficiency. In several studies dementia has been related to low serum cobalamin levels. Physicians should be liberal of cobalamin therapy. The window of opportunity for effective intervention may be as short as one year from the onset of medical symptoms. At last a compilation of recommendations is given.

[Reliability and validity of the French version of the first part of the Appropriateness Evaluation Protocol (AEPf): pertinent criteria of hospitalization stay]. / Reproductibilité et validité de la version française de la première partie de l'Appropriateness Evaluation Protocol (AEPf): critères de pertinence des journées d'hospitalisation.

BACKGROUND: The Appropriateness Evaluation Protocol (AEP) is a tool used to identify hospitalization days that are appropriate with respect to simple technical criteria, and the reasons for hospitalization days that do not meet these criteria. The goal of the study was to validate the clinical criteria of AEPf, required for identifying the reasons which explain these inappropriate hospital days. METHODS: The validity of a French version of criteria of appropriateness (AEPf) was assessed in a sample of 502 hospital days in medical and surgical wards of six French teaching hospitals. The reliability of the AEPf-based conclusions was studied by the measure of the concordance between two independent measures of AEPf for the same hospital day. Validity of AEPf was studied by the measure of the concordance between AEPf-based conclusions and the judgments of physicians using implicit criteria to assess the necessity of the hospital day studied. The degree of concordance was estimated by the Kappa coefficient. RESULTS: AEPf reproducibility was high (Kappa coefficient: 0.81; 95% confidence interval (95% CI): 0.76-0.87). Validity was also high (Kappa coefficient: 0.61; 95% CI: 0.53-0.68). CONCLUSION: The French version of the AEP was thus shown to be both reliable and valid to identify hospitalisation days appropriate with respect to hospital's technical equipment and specific resources. However, the reproducibility of the assessment of reasons for hospital days that did not meet AEP criteria will require a validation.

[Prolonged suppressive L-thyroxine therapy. Longitudinal study of the effect of LT4 on bone mineral density and bone metabolism markers in 71 patients]. / Traitement prolongé par L-thyroxine à visée suppressive. Etude longitudinale de l'influence de la LT4 sur la densité minérale osseuse et les marqueurs osseux métaboliques chez 71 patients.

OBJECTIVES: A prospective longitudinal study was conducted to investigate the influence of prolonged suppressive L-thyroxin therapy on bone density and biochemical markers of bone remodeling. PATIENTS AND METHODS: Seventy-one patients (including 28 menopaused women) taking long-term L-T4 for thyroid carcinoma were divided into 3 groups according to their TSH level: low (TSH < 0.04 mlU/l), moderate (0.04 TSH < or = 0.10 mlU/l) and high (TSH > 0.10 mlU/l). Bone density was measured in lumbar vertebrae annually for a mean 4.5 years. Bone metabolism markers were measured over a 4 year period. Bone density measurements of the femur were also obtained for 2 years in 16 menopaused women. RESULTS: Lumbar bone density did not decline whatever the TSH level or the duration of L-T4 treatment. Likewise for menopaused women without substitution estroprogesterone therapy. Over the 4 years, biochemical markers of bone formation, including bone alkaline phosphatases and osteocalcin, or of bone resorption, including urinary hydroxyprolin, did not vary. In addition, in menopaused women, femoral bone density was not significantly lowered over the 2 years follow-up. No lumbar or femoral osteopenia was observed in these patients taking L-thyroxin, even for those with complete TSH blockade. Biochemical markers did not demonstrate a significant acceleration of bone turnover during prolonged administration of L-T4 at suppressive levels.

[Discharge from the geriatric clinic: factors predicting independent living at home]. / Entlassung aus der Geriatrieklinik: Faktoren, die ein Verbleiben zu Hause voraussagen.

This article presents the predictors for living at home 3 months, 6 months, 12 months, and 24 months after hospitalization in a geriatric clinic. The multivariate regression analysis revealed the predictive factors for living at home after 3 months: Incontinence, functional status judged by the physician, and balance performance. For living at home at 6 months, balance performance, handgrip were predictive, and at 12 months, balance performance, physicians judgement of functional abilities and Barthel-Index had the most predictive value. The only factor that was recognized to be predictive for living at home at 24 months was the physician's judgement of the functional abilities of the patient. It is concluded that the functional status measured by observation but preferably by performance is of predictive value for living at home from 6 months to 12 months after acute hospitalization.

[Epidemiology of falls and hip fractures]. / Epidemiologie des Sturzes und der Hüftfraktur.

The risk of falling increases with age and with many of the disorders common in late life. Approximately 35 to 40% of community-dwelling people over the age of 65 and up to 50% of institutionalized elderly fall at least once every year. The incidence is highest in women and the very old. Hip fracture, one of the most serious injuries associated with falls, assumes epidemic proportions in old people. In addition to physical injury, falls can have other serious consequences for the older person. Repeated falls are a common reason for the admission of previously independent elderly persons to long-term care institutions. This article examines why older people fall and what factors place persons at risk for falling. The multiple reasons for an inconsistency of the epidemiological data are discussed.

[Approach to the rational management of patients with dementia]. / Ansätze zu einem rationalen Management der Demenzerkrankungen.

In senile dementia the clinical presentation is not only determined by the mental deficits but also by affective, behavioral and somatic symptoms. Some sequelae are regularly associated with the process and the course of dementia, and therefore largely predictable and preventable. Identification of the complications commonly associated with this disease complex allows prevention and early treatment of states incriminating the natural course of the disease. By this approach a rational management of senile dementia can be achieved.

[Evaluating gait disorders in geriatrics]. / Beurteilung der Gangstörungen in der Geriatrie.

Gait disorders in the elderly are a major cause of falls and accidents. They also interfere badly with the quality of life and the psychosocial well-being. The prevalence of these disorders is very high: 15% of the persons over 65 years and about 25% of those over 75 years suffer from gait disorders. The cause of gait disorders can be a specific disease, but in the elderly, multiple causes are much more frequent. In the elderly, the analysis of gait disorders consists not only of a diagnostic work-up, but also of a comprehensive geriatric and functional gait assessment. A minimal gait assessment includes a special clinical examination, an instrumental analysis of gait speed and a functional assessment of gait and balance by standard tests. In this article the relevant methods of a practical gait assessment are presented and some basic aspects of treatments are discussed.

Diagnostic value of reversibility of chronic airway obstruction to separate asthma from chronic bronchitis: a statistical approach.

Our aim was to assess the usefulness of tests of reversibility of airways obstruction (AO) in the differential diagnosis of asthma (A) and chronic bronchitis (CB). We selected on strict clinical criteria 20 CB and 32 A patients with stable AO and measured maximal forced expiratory flows before and after increasing doses of inhaled salbutamol. The highest sensitivity (Se), specificity (Sp) and likelihood ratio (L) were obtained when the improvement in forced expiratory volume in one second (FEV1) was expressed as a percentage of predicted FEV1. Se, Sp and L were 0.97, 0.95 and 19.3 (highest possible L: 20) for an increase of 10% of predicted FEV1 on 0.2 mg of salbutamol, and 1.0, 1.0 and 20, respectively, for an increase of 15% on 1 mg of salbutamol. Conversely, L was only 2.8 when the widely used increase in FEV1 of 20% over baseline was tested. In a second group of 42 unselected patients, who were referred to the laboratory for routine lung function testing with a presenting diagnosis of A or CB, L was only 5.5 when the 10% increase in predicted FEV1 was used and even lower for the classical 20% increase over baseline FEV1. We submit that routine tests of reversibility of AO have little diagnostic usefulness in unselected patients with AO and that the commonly used criteria of 15 or 20% increase in FEV1 over baseline are of no value in separating A from CB.

[Lumbar spinal stenosis syndrome in the experience of a rheumatologic-geriatric clinic]. / Das Syndrom des engen Lumbalkanals in der Erfahrung einer rheumatologisch-geriatrischen Klinik.

In the geriatric patient differential diagnosis of low back pain with sciatica includes degenerative lumbar spinal stenosis, affecting the central canal, the lateral recesses or both. Symptoms usually begin in the sixth decade, but may occur earlier if spinal degeneration is superimposed on congenital stenosis. In the elderly early diagnosis is more difficult to establish, because of the bewildering medical problems and the multiple symptoms rooted in the polypathy and polymorbidity of old age. Typical symptoms include low back pain, claudicatory pains, and paraesthesias of the legs, typically aggravated by standing and relieved by rest. In our series they were present in 100%, 94% and 56% respectively. In our series, the most important clinical investigations confirming diagnosis were pain provocation by reclining and pain relief by inclination (present in 69% of patients) and combined radiographic examination including plain films, computed tomography and myelography. In our experience myelography proved the best single method for early diagnosis. In our elderly patients lateral stenosis was predominant, and therefore lateral decompression by foraminotomy, generally combined with flavectomy, was the most important surgical procedure. In cases with combined lateral and central stenosis, hemilaminectomy or facetectomy was also performed. In follow-up 1 to 5 years after the operation the success rate, determined by very restrictive criteria, was 87%. Therefore, and because failure to establish early diagnosis potentially leads to definitive invalidity, degenerative lumbar spinal stenosis should be considered more frequently in the differential diagnosis of low back pain of the elderly.(ABSTRACT TRUNCATED AT 250 WORDS)

[Diagnosis and therapy of hypotensive cardiovascular disorders in old age]. / Diagnose und Therapie der hypotonen Kreislaufstörungen im Alter.

Postural hypotension, defined as a fall in systolic pressure of 20 mmHg or more on standing, and other hypotensive conditions are major problems in geriatric medicine. In this article the physiology and the pathology of orthostatic blood pressure regulation in the elderly are reviewed. Proposals are made for the diagnostic evaluation of patients with postural hypotension and for steps to be taken in therapeutic management.

An efficient structure for a medical information database in a general hospital.

This paper describes a Medical Information System (conversational in real-time). SIGMED, which is used in the French hospital of Angers. Its main feature is its original organization which (i) allows one to follow a patient's history in space and time with a limited number of medical items and the whole set of administration ones and makes it possible to carry and (ii) the possibility of various epidemiological studies relating to medical speciality records which contain all the medical information related to a patient's examination and/or hospitalization.

[Reproducibility and prognostic value of Gleason's and Gaeta's histological grades in prostatic carcinoma]. / Reproductibilité et valeur pronostique des grades histologiques de Gleason et de Gaeta dans les carcinomes de la prostate.

Two histopathologic grading systems for prostatic adenocarcinomas are reevaluated: the Gleason system and the Gaeta system. Two pathologists reviewed 234 specimens to assess reproducibility. Exact agreement is achieved in 88% with the Gaeta system, in 65% with the Gleason system. Nevertheless, agreement to within one score unit is achieved in 94% with the Gleason grading. One pathologist's autoreproducibility exceed 80% with either system. Actuarial survival curves and mortality index (deaths per patient-year of follow-up) provided evidence of their predictive value. Regardless of the clinical stage these two grading systems select groups of patients sharing a good, intermediate or bad prognosis but none can predict a given patient's accurate survival. The Gleason system would allow a better discrimination between poorly and highly aggressive tumors of intermediate grade.