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Semantic interoperability, a prerequisite to eHealth projects, relies on sharing both information and knowledge models between information systems. Two of the standards of information models are HL7 v3 and the European norm, EN13606/OpenEHR. The paper compares both standards on a fragment of the prenatal medical record, the APGAR score. Two factors are compared: the formal representation of both information models, and the binding to knowledge models. The HL7v3 perinatality DMIM specification and the OpenEHR APGAR archetype were used. HL7v3 appears to be more formal than OpenEHR and able to represent in an easier way the clinical context. For both standards, the binding to reference terminologies such as LOINC is poor. We provide recommendations to improve the standards.

Introduction: We assessed the in vivo effects of terbutaline, a beta2-agonist assumed to reduce microvascular permeability in acute lung injury., Methods: We used a recently developed broncho-alveolar lavage (BAL) technique to repeatedly measure (every 15 min. for 4 hours) the time-course of capillary-alveolar leakage of a macromolecule (fluorescein-labeled dextran) in 19 oleic acid (OA) lung injured dogs. BAL was performed in a closed lung sampling site, using a bronchoscope fitted with an inflatable cuff. Fluorescein-labeled Dextran (FITC-D70) was continuously infused and its concentration measured in plasma and BAL fluid. A two-compartment model (blood and alveoli) was used to calculate KAB, the transport rate coefficient of FITC-D70 from blood to alveoli. KAB was estimated every 15 minutes over 4 hours. Terbutaline intra-venous perfusion was started 90 min. after the onset of the injury and then continuously infused until the end of the experiment., Results: In the non-treated injured group, the capillary-alveolar leakage of FITC-D70 reached a peak within 30 minutes after the OA injury. Thereafter the FITC-D70 leakage decreased gradually until the end of the experiment. Terbutaline infusion, started 90 min after injury, interrupted the recovery with an aggravation in FITC-D70 leakage., Conclusions: As cardiac index increased with terbutaline infusion, we speculate that terbutaline recruits leaky capillaries and increases FITC-D70 leakage after OA injury. These findings suggest that therapies inducing an increase in cardiac output and a decrease in pulmonary vascular resistances have the potential to heighten the early increase in protein transport from plasma to alveoli within the acutely injured lung.

The study compares the effectiveness of Bayesian networks versus Decision Trees for predicting access to renal transplant waiting list in a French healthcare network. The data set consisted in 809 patients starting renal replacement therapy. The data were randomly divided into a training set (90%) and a validation set (10%). Bayesian network and CART decision tree were built on the training set. Their predictive performances were compared on the validation set. The age variable was found to be the most important factor in both models. Both models were highly sensitive and specific: sensitivity 90.0% (95%CI: 76.8-100), specificity 96.7% (95%CI: 92.2-100). Moreover, the models were complementary since the Bayesian network provided a global view of the variables' associations while the decision tree was more easily interpretable by physicians. These approaches provide insights on the current care process. This knowledge could be used for optimizing the healthcare process.

There is a growing interest in imaging techniques as non-invasive means of quantitatively measuring regional lung structure and function. Abnormalities in lung ventilation due to alterations in airway function such as those observed in asthma and COPD are highly heterogeneous, and experimental methods to study this heterogeneity are crucial for better understanding of disease mechanisms and drug targeting strategies. In severe obstructive diseases requiring mechanical ventilation, the optimal ventilatory strategy to achieve recruitment of poorly ventilated lung zones remains a matter of considerable debate. We have used synchrotron radiation computed tomography (SRCT) for the in vivo study of regional lung ventilation and airway function. This imaging technique allows direct quantification of stable Xenon (Xe) gas used as an inhaled contrast agent using K-edge subtraction imaging. Dynamics of Xe wash-in can be used to calculate quantitative maps of regional specific lung ventilation. More recently, the development of Spiral-CT has allowed the acquisition of 3D images of the pulmonary bronchial tree and airspaces. This technique gives access to quantitative measurements of regional lung volume, ventilation, and mechanical properties. Examples of application in an experimental model of allergic asthma and in imaging lung recruitment as a function of mechanical ventilation parameters will be presented. The future orientations of this technique will be discussed.

The benefit of prescribing angiotensin-converting enzyme inhibitors (ACEi) and angiotensin-II receptor antagonists (ARB) to kidney transplant recipients remains controversial. We investigated determinants and prescribing patterns of ACEi/ARB during the first year following kidney transplantation. All recipients of a first kidney transplant performed at the university hospital of Nancy (France) between January 1997 and June 2004 were included. Determinants of ACEi/ARB prescription were identified by Cox models among various recipient characteristics (at transplantation and during follow-up), donor characteristics and transplant parameters. Of 491 patients, 28.9% started using ACEi/ARB during the year after transplantation, and 26.9% were taking them at one yr. Recipient determinants of ACEi/ARB use were male sex (HR: 1.82, p = 0.003), pre-transplant hypertension (HR: 2.27, p = 0.0002) and ACEi/ARB administration (HR: 1.85, p = 0.002), post-transplant proteinuria (HR: 1.62, p < 0.0001) and anemia (HR: 4.08, p < 0.0001). Glomerular filtration rate level was not associated with ACEi/ARB use. Post-transplant hypercholesterolemia (HR: 0.42, p = 0.013) and higher donor age (HR: 0.98, p = 0.015) were associated with a lower likelihood of ACEi/ARB use. Fewer HLA mismatches (HR: 1.16, p = 0.029) and shorter cold ischemia duration (HR: 1.02, p = 0.045) were also independent predictors of ACEi/ARB use. Regardless of recipient characteristics, nephrologists were more likely to prescribe ACEi/ARB after kidney transplantation when the transplant parameters were favorable.

Objectives: We developed a modified broncho-alveolar lavage (BAL) technique in order to perform repeated measurements of capillary-alveolar leakage of a macromolecule in oleic acid (OA)-induced lung injury., Methods: BAL was performed in anesthetized dogs in a closed lung sampling site, using a bronchoscope fitted with an inflatable cuff. Fluorescein-labeled Dextran (FITC-D70) was continuously infused and its concentration measured in plasma and BAL fluid. A two-compartment model (blood and alveoli) was used to calculate K(AB), the transport-rate coefficient of FITC-D70 from blood to alveoli. K(AB) was estimated every 15 minutes over three hours., Results: K(AB), close to zero at base-line both in control (n = 3) and in OA-injured lungs (n = 7), reached a peak in permeability 30 minutes after the induction of OA injury (K(AB) = 1.43 +/- 0.31 . 10(- 3) . minutes(- 1)), followed by a slow recovery., Conclusions: We conclude that this technique allows the monitoring of capillary-alveolar transport of macromolecules in in vivo experimental models. This monitoring may prove useful to study the mechanisms of the exudative stage of acute lung injury and to test therapies aimed at slowing the alveolar accumulation of plasma proteins and procoagulant factors that contribute to alveolar fibrosis.

In K-edge subtraction (KES) imaging with synchrotron radiation computed tomography (SRCT), two images are taken simultaneously using energies above and below the K-absorption edge of a contrast agent. A logarithmic difference image reveals the contrast agent concentration with good accuracy. Similarly, in temporal subtraction imaging (TSI) the reference image is taken before the introduction of the contrast agent. Quantitative comparisons of in vivo images of rabbit lung indicated that similar results for concentrations of iodine in blood vessels and xenon in airways are obtained by KES and TSI, but the level of noise and artifacts was higher in the latter. A linear fit showed that in the lung parenchyma rho(TSI) = (0.97 +/- 0.03)rho(KES) + (0.00 +/- 0.05) for xenon and rho(TSI) = (1.21 +/- 0.15)rho(KES) + (0.0 +/- 0.1) for iodine. For xenon the calculation of time constant of ventilation gave compatible values for both of the methods. The two methods are combined for the simultaneous determination of the xenon concentration (by KES) and the iodine concentration (by TSI) in lung imaging, which will allow simultaneous in vivo determination of ventilation and perfusion.

Evaluation of adult candidates for kidney transplantation diverges from one centre to another. Our purpose was to assess the suitability of Bayesian method for describing the factors associated to registration on the waiting list in a French healthcare network. We have found no published paper using Bayesian method in this domain. Eight hundred and nine patients starting renal replacement therapy were included in the analysis. The data were extracted from the information system of the healthcare network. We performed conventional statistical analysis and data mining analysis using mainly Bayesian networks. The Bayesian model showed that the probability of registration on the waiting list is associated to age, cardiovascular disease, diabetes, serum albumin level, respiratory disease, physical impairment, follow-up in the department performing transplantation and past history of malignancy. These results are similar to conventional statistical method. The comparison between conventional analysis and data mining analysis showed us the contribution of the data mining method for sorting variables and having a global view of the variables' associations. Moreover theses approaches constitute an essential step toward a decisional information system for healthcare networks.

Background: Evaluation of adult candidates for kidney transplantation diverges from one centre to another. Concurrently, ethnic background, female gender, late referral to a nephrologist, distance from transplantation department and private ownership of a dialysis facility have been associated with poor access to kidney transplantation. We assessed determinants of access to a waiting list in a French community-based network of care., Methods: From July 1997 to June 2003, 1725 adults living in Lorraine, who started renal replacement therapy in one of the 13 facilities of the network, were included. We compared, first, the patients registered on the waiting list with those not registered and, second, the patients registered before starting dialysis with those registered after., Results: Using logistic regression, registration on the waiting list was exclusively associated with age and medical factors, except for one variable: medical follow-up in the department performing transplantation [odds ratio (OR): 1.67 (95%CI: 1.05-2.67)]. Registration before starting dialysis was not associated with medical factors but with age [OR of patients younger than 45 years vs those older than 65 years: 3.85 (95%CI: 1.05-24.92)] and medical follow-up in the department performing transplantation [OR: 3.56 (95%CI: 1.98-6.67)]., Conclusions: In a French community-based network, patients followed by the nephrology department performing transplantation are more likely to be registered on the transplant waiting list early in the course of chronic kidney disease. Age over 55 per se is a considerable barrier to access to kidney transplantation. Medical guidelines should allow a standardization of criteria for registration.

We studied the kinetics of proximal and distal bronchial response to histamine aerosol in healthy anesthetized and mechanically ventilated rabbits up to 60 min after histamine administration using a novel xenon-enhanced synchrotron radiation computed tomography imaging technique. Individual proximal airway constriction was assessed by measuring the luminal cross-sectional area. Distal airway obstruction was estimated by measuring the ventilated alveolar area after inhaled xenon administration. Respiratory system conductance was assessed continuously. Proximal airway cross-sectional area decreased by 57% of the baseline value by 20 min and recovered gradually but incompletely within 60 min. The ventilated alveolar area decreased immediately after histamine inhalation by 55% of baseline value and recovered rapidly thereafter. The results indicate that the airway reaction to inhaled histamine and the subsequent recovery are significantly slower in proximal than in distal bronchi in healthy rabbit. The findings suggest that physiological reaction mechanisms to inhaled histamine in the airway walls of large and small bronchi are not similar.

The authors previously provided evidence of synchrotron radiation computed tomography (SRCT) efficacy for quantitative in vivo brain perfusion measurements using monochromatic X-ray beams. However, this technique was limited for small-animal studies by partial volume effects. In this paper, high-resolution absolute cerebral blood volume and blood-brain barrier permeability coefficient measurements were obtained on a rat glioma model using SRCT and a CCD camera (47x47 microm2 pixel size). This is the first report of in vivo high-resolution brain vasculature parameter assessment. The work gives interesting perspectives to quantify brain hemodynamic changes accurately in healthy and pathological small animals.

The aim of this study was to assess the feasibility of a novel respiration-gated spiral synchrotron radiation computed tomography (SRCT) technique for direct quantification of absolute regional lung volumes, using stable xenon (Xe) gas as an inhaled indicator. Spiral SRCT with K-edge subtraction using two monochromatic x-ray beams was used to visualize and directly quantify inhaled Xe concentrations and airspace volumes in three-dimensional (3D) reconstructed lung images. Volume measurements were validated using a hollow Xe-filled phantom. Spiral images spanning 49 mm in lung height were acquired following 60 breaths of an 80% Xe-20% O2 gas mixture, in two anaesthetized and mechanically ventilated rabbits at baseline and after histamine aerosol inhalation. Volumetric images of 20 mm lung sections were obtained at functional residual capacity (FRC) and at end-inspiration. 3D images showed large patchy filling defects in peripheral airways and alveoli following histamine provocation. Local specific lung compliance was calculated based on FRC/end-inspiration images in normal lung. This study demonstrates spiral SRCT as a new technique for direct determination of regional lung volume, offering possibilities for non-invasive investigation of regional lung function and mechanics, with a uniquely high spatial resolution. An example of non-uniform volume distribution in rabbit lung following histamine inhalation is presented.

Relative differences in environment, behaviour, social composition as well as access to health care tend to suggest that levels of health may vary between urban and rural areas. The aim of this study was to identify rural-urban variations in mortality risks in the region of Brittany for the period from 1988 to 1992. The definition of urban and rural areas used adhered to that of the zoning of urban areas established by the INSEE (the National Statistical Office). The amalgamation of all causes of standardised mortality ratios (SMR) show only a moderately increased risk in the rural areas compared with the overall regional level (+4% in men, +5-7% in women). The analysis of cause specific SMRs display higher rural mortality for cardiovascular diseases and external causes of death, road traffic accidents in particular (+24% in men). Among all specific causes investigated, only lung cancer mortality risk appears to be higher in urban areas.

The efficacy of antimicrobial agents against pulmonary infections depends on their local concentrations in the lung. The aims of the present study were to: 1) compare technetium-99m diethylenetriaminepenta-acetic acid (99mTc-DTPA) and urea as markers of epithelial lining fluid (ELF) dilution for measuring ELF concentrations of pharmaceuticals; 2) quantify ELF cefepime concentrations in normal and injured lung; and 3) measure the increase in permeability to cefepime following oleic acid-induced acute lung injury. A modified bronchoalveolar lavage technique, based on equilibration of infused 99mTc-DTPA, was used to measure ELF volume. Cefepime was administered intravenously at steady plasma levels. Six serial bronchoalveolar lavages were performed 5 h after the beginning of infusion. ELF to plasma cefepime concentration ratios were 95 +/- 17 and 100 +/- 14.5% in normal and injured lung respectively. When urea was used as marker, cefepime concentration ratios were underestimated at 16.4 +/- 2.7 and 73.9 +/- 8.4% respectively. Cefepime blood/ airspace clearance increased from 3.8 +/- 0.7 micro x min(-1) in controls to 39.8 +/- 4.9 microL x min(-1) in acute lung injury. It was concluded that: 1) cefepime concentrations in epithelial lining fluid were in equilibrium with those in plasma in both normal and injured lung after 5 h at steady plasma concentrations; 2) epithelial lining fluid cefepime concentration by the urea method was much less underestimated in injured versus normal lung; and 3) acute lung injury induces a 10-fold elevation of cefepime blood/airspace clearance.

A respiration-gated synchrotron radiation computed tomography (SRCT) technique, which allows visualization and direct quantification of inhaled stable xenon gas, was used to study the effect of tidal volume (Vt) on regional lung ventilation. High-resolution maps (pixel size 0.35 x 0.35 mm) of local washin time constants (tau) and regional specific ventilation were obtained in five anesthetized, paralyzed, and mechanically ventilated rabbits in upright body position at the fourth, sixth, and eighth dorsal vertebral levels with a Vt from 4.9 +/- 0.3 to 7.9 +/- 0.4 ml/kg (means +/- SE). Increasing Vt without an increase in minute ventilation resulted in a proportional increase of mean specific ventilation up to 65% in all studied lung levels and reduced the scattering of washin tau values. The tau values had log-normal distributions. The results indicate that an increase in Vt decreases nonuniformity of intraregional ventilatory gas exchange. The findings suggest that (SRCT) provides a new quantitative tool with high spatial discrimination ability for assessment of changes in peripheral pulmonary gas distribution during mechanical ventilation.

This study assessed the early vascular reactivity changes in mice after exposure to 14 days intermittent hypoxia (IH) with active or inactive sympathetic nervous system (SNS). Hindquarters of mice exposed to 14 days of IH, sham exposed mice or unhandled mice were perfused at constant flow with Krebs-Albumin (5%). Changes in perfusion pressure were assessed after injection of several doses of norepinephrine in anaesthetized mice (active SNS) or in euthanized mice (inactive SNS). Response to several doses of acetylcholine was recorded after precontraction of hindquarter vascular bed by methoxamine in euthanized mice. Vasoconstrictor response was increased after IH for high dose of NE (50 microg) in euthanized mice and for all doses of NE (2-10-50 microg) in anaesthetized mice, but no change in vasodilatation was observed. These findings suggest that 14 days of IH altered vascular reactivity of mice hindquarter in an early pattern. Vasoconstriction was enhanced, particularly with active SNS, while there was no dysfunction of endothelium-relaxation.

Small airways play a key role in the distribution of ventilation and in the matching of ventilation to perfusion. The purpose of this study was to introduce an imaging method that allows measurement of regional lung ventilation and evaluation of the function of airways with a small diameter. The experiments were performed at the Medical Beamline of the European Synchrotron Radiation Facility. Monochromatic synchrotron radiation beams were used to obtain quantitative respiration-gated images of lungs and airways in two anaesthetized and mechanically ventilated rabbits using inhaled stable xenon (Xe) gas as a contrast agent. Two simultaneous images were acquired at two different energies, above and below the K-edge of Xe. Logarithmic subtraction of the two images yields absolute Xe concentrations. This technique is known as K-edge subtraction (KES) radiography. Two-dimensional planar and CT images were obtained showing spatial distribution of Xe concentrations within the airspaces, as well as the dynamics of filling with Xe. Bronchi down to 1 mm in diameter were visible both in the subtraction radiographs and in tomographic images. Absolute concentrations of Xe gas were calculated within the tube carrying the inhaled gas mixture, small and large bronchi, and lung tissue. Local time constants of ventilation with Xe were obtained by following the evolution of gas concentration in sequential computed tomography images. The results of this first animal study indicate that KES imaging of lungs with Xe gas as a contrast agent has great potential in studies of the distribution of ventilation within the lungs and of airway function, including airways with a small diameter.

Objective: Measurement of capillary-alveolar permeability to fluorescein isothiocyanate-dextran (FITC-D) (molecular mass, 71,300 daltons) by a sequential bronchoalveolar lavage (BAL) technique., Design: Animal research., Setting: The Department of Physiology at a scientific and medical university., Subjects: Nine anesthetized and mechanically ventilated dogs., Interventions: Two separate experiments were performed in each subject-an initial control experiment followed by an oleic acid-induced lung injury. The indicator was administered at constant blood concentration before serial BAL including eight fluid instillation-recovery cycles., Measurements: Plasma to BAL solute clearance at saturation (capillary-alveolar clearance at saturation, mL/min) was calculated and normalized to lavage fluid volume (measured by 1251 serum albumin dilution) to obtain a transport rate (TR) constant., Main Results: TR for FITC-D70 was 4.0+/-0.8 and 46.1+/-18.1 x 10(-5) x min(-1) in control and injured lung, respectively (p < .02). Capillary-alveolar clearance of FITC-D70 was not affected by the lavage procedure itself. TR reflected essentially epithelial permeability in normal lung and combined epithelial and endothelial permeability in injured lung. A significant correlation was found between cardiac output and TR in injured lung., Conclusions: Saturation BAL allowed us to estimate capillary-alveolar macromolecule permeability in vivo in dogs. Further study may allow bedside evaluation of lung injury by BAL in patients.

Background: Distortion of the pressure wave by a liquid-filled catheter-transducer system leads most often to an overestimation in systolic arterial blood pressure in pulmonary and systemic circulations. The pressure distortion depends on the catheter-transducer frequency response. Many monitoring systems use either mechanical or electronic filters to reduce this distortion. Such filters assume, however, that the catheter-transducer frequency response does not change over time. The current study aimed to study the changes with time of the catheter-transducer frequency response and design a flush procedure to reverse these changes back to baseline., Methods: An in vitro setup was devised to assess the catheter-transducer frequency response in conditions approximating some of those met in a clinical environment (slow flushing, 37 degrees C, 48-h test). Several flush protocols were assessed., Results: Within 48 h, catheter-transducer natural frequency decreased from 17.89 +/- 0.36 (mean +/- SD) to 7.35 +/- 0.25 Hz, and the catheter-transducer damping coefficient increased from 0.234 +/- 0.004 to 0.356 +/- 0.010. Slow and rapid flushing by the flush device built into the pressure transducer did not correct these changes, which were reversed only by manual fast flush of the transducer and of the catheter. These changes and parallel changes in catheter-transducer compliance may be explained by bubbles inside the catheter-transducer., Conclusions: Catheter-transducer-induced blood pressure distortion changes with time. This change may be reversed by a manual fast flush or "rocket flush" procedure, allowing a con. stant correction by a filter.

We used an original saturation bronchoalveolar lavage (SBAL) technique (Eur. Respir. J. 1995;8[Suppl. 19]398S) to quantitate lung epithelial lining fluid volume (VELF) in dogs in two separate experiments: control and after oleic-acid-induced injury. We confirmed the hypothesis that 99mTc-DTPA, infused at constant plasma activity, reaches equilibrium with epithelial lining fluid after 90 min. We performed eight sequential lavages 215 min after beginning the infusion of 99mTc-DTPA. 99mTc-DTPA activity (Qn) in the lavage fluid increased linearly with time, suggesting transport from the plasma into the alveoli during lavage. We extrapolated Qn to time zero (Q0), when 99mTc-DTPA was not affected by lavage. VELF was calculated from: VELF = Q0/Cp, (Cp: 99mTc-DTPA mean plasma activity). 125I-albumin was used as a nondiffusible alveolar indicator to measure the fluid volume present in the lavaged segment (Vt,n). Vt,n plateaud for n >= 4. VELF/Vt,n(n = 5,8) was 1.7 +/- 0.4 and 25.0 +/- 4.4% (p < 0.05) in control and injury experiments, respectively. SBAL allowed reliable measurements of VELF and detection of alveolar edema fluid in the injured lung.

On the basis of changes in capillary filtration coefficient (Kfc) in 24 rabbit lungs, we determined whether elevations in pulmonary venous pressure (Ppv) or blood flow (BF) produced differences in filtration surface area in oleic acid-injured (OA) or control (Con) lungs. Lungs were cyclically ventilated and perfused under zone 3 conditions by using blood and 5% albumin with no pharmacological modulation of vascular tone. Pulmonary arterial, venous, and capillary pressures were measured by using arterial, venous, and double occlusion. Before and during each Kfc-measurement maneuver, microvascular/total vascular compliance was measured by using venous occlusion. Kfc was measured before and 30 min after injury, by using a Ppv elevation of 7 cmH2O or a BF elevation from 1 to 2 l . min-1 . 100 g-1 to obtain a similar double occlusion pressure. Pulmonary arterial pressure increased more with BF than with Ppv in both Con and OA lungs [29 +/- 2 vs. 19 +/- 0.7 (means +/- SE) cmH2O; P < 0. 001]. In OA lungs compared with Con lungs, values of Kfc (200 +/- 40 vs. 83 +/- 14%, respectively; P < 0.01) and microvascular/total vascular compliance ratio (86 +/- 4 vs. 68 +/- 5%, respectively; P < 0.01) increased more with BF than with Ppv. In conclusion, for a given OA-induced increase in hydraulic conductivity, BF elevation increased filtration surface area more than did Ppv elevation. The steep pulmonary pressure profile induced by increased BF could result in the recruitment of injured capillaries and could also shift downstream the compression point of blind (zone 1) and open injured vessels (zone 2).