Canal de Provence

Presented at the 2002 USCID/EWRI conference, Energy, climate, environment and water - issues and opportunities for irrigation and drainage on July 9-12 in San Luis Obispo, California.Includes bibliographical references.Measurement network on hydraulic system includes many sensors subject to failure or deviation, and spread over a huge area. In addition discharge and volume measurements in open channel hydraulic networks are characterized by large uncertainties. To overcome this kind of problem, in process control industrial applications, data reconciliation is more and more used. The objective of the data reconciliation is to take advantage of information redundancy on a system to make a cross-checking of real-time measurements. Using this information redundancy, a data reconciliation module allows to detect inconsistent measurements, measurement deviations and provides corrected values whether the initial measurements are valid, biased or invalid. A derived consequence is to better schedule the maintenance of sensors. A data reconciliation module, based on the measurements from the hydraulic network, has been recently developed and implemented in the SCP's supervisory system. The software has initially been used on a daily basis to check the measured flow on the main canal. It has then been adapted in order to run every 15 minutes on a distribution network including pipes, canals, and tanks. The paper presents first the theory of the Canal de Provence data reconciliation application. The basic model is an hydraulic network with a series of nodes corresponding to balance equations (inflows, outflows, and storage). Constrained data reconciliation is used in order to satisfy the non-negativity of the hydraulic variables and the mass balance relations. The results are corrected values for measured variables and proposed values for non-measured quantities. A statistical analysis of the results is performed. This analysis allows to evaluate the uncertainties attached to the estimated flows and volume values. It allows also to detect invalid measurements, drift of sensors and to decide which maintenance operations to perform. Secondly, field examples are presented: measured and re-estimated flow values with their standard deviations, detection of invalid sensors, performed maintenance operation. The data reconciliation is situated just after the measurement process and takes place in the decision process for diagnosis, identification and control

Combination therapy versus monotherapy: a randomised pilot study on the evolution of inflammatory parameters after ventilator associated pneumonia [ISRCTN31976779]

INTRODUCTION: Combination antibiotic therapy for ventilator associated pneumonia (VAP) is often used to broaden the spectrum of activity of empirical treatment. The relevance of such synergy is commonly supposed but poorly supported. The aim of the present study was to compare the clinical outcome and the course of biological variables in patients treated for a VAP, using a monotherapy with a beta-lactam versus a combination therapy. METHODS: Patients with VAP were prospectively randomised to receive either cefepime alone or cefepime in association with amikacin or levofloxacin. Clinical and inflammatory parameters were measured on the day of inclusion and thereafter. RESULTS: Seventy-four mechanically ventilated patients meeting clinical criteria for VAP were enrolled in the study. VAP was microbiologically confirmed in 59 patients (84%). Patients were randomised to receive cefepime (C group, 20 patients), cefepime with amikacin (C-A group, 19 patients) or cefepime with levofloxacin (C-L group, 20 patients). No significant difference was observed regarding the time course of temperature, leukocytosis or C-reactive protein level. There were no differences between length of stay in the intensive care unit after infection, nor in ventilator free days within 28 days after infection. No difference in mortality was observed. CONCLUSION: Antibiotic combination using a fourth generation cephalosporin with either an aminoside or a fluoroquinolone is not associated with a clinical or biological benefit when compared to cephalosporin monotherapy against common susceptible pathogens causing VAP

Annals of Intensive Care

peer reviewe

The Role of Imaging in the Detection of Non-COVID-19 Pathologies during the Massive Screening of the First Pandemic Wave

peer reviewedDuring the COVID-19 pandemic induced by the SARS-CoV-2, numerous chest scans were carried out in order to establish the diagnosis, quantify the extension of lesions but also identify the occurrence of potential pulmonary embolisms. In this perspective, the performed chest scans provided a varied database for a retrospective analysis of non-COVID-19 chest pathologies discovered de novo. The fortuitous discovery of de novo non-COVID-19 lesions was generally not detected by the automated systems for COVID-19 pneumonia developed in parallel during the pandemic and was thus identified on chest CT by the radiologist. The objective is to use the study of the occurrence of non-COVID-19-related chest abnormalities (known and unknown) in a large cohort of patients having suffered from confirmed COVID-19 infection and statistically correlate the clinical data and the occurrence of these abnormalities in order to assess the potential of increased early detection of lesions/alterations. This study was performed on a group of 362 COVID-19-positive patients who were prescribed a CT scan in order to diagnose and predict COVID-19-associated lung disease. Statistical analysis using mean, standard deviation (SD) or median and interquartile range (IQR), logistic regression models and linear regression models were used for data analysis. Results were considered significant at the 5% critical level (p < 0.05). These de novo non-COVID-19 thoracic lesions detected on chest CT showed a significant prevalence in cardiovascular pathologies, with calcifying atheromatous anomalies approaching nearly 35.4% in patients over 65 years of age. The detection of non-COVID-19 pathologies was mostly already known, except for suspicious nodule, thyroid goiter and the ascending thoracic aortic aneurysm. The presence of vertebral compression or signs of pulmonary fibrosis has shown a significant impact on inpatient length of stay. The characteristics of the patients in this sample, both from a demographic and a tomodensitometric point of view on non-COVID-19 pathologies, influenced the length of hospital stay as well as the risk of intra-hospital death. This retrospective study showed that the potential importance of the detection of these non-COVID-19 lesions by the radiologist was essential in the management and the intra-hospital course of the patients

The first wave of COVID-19 in Intensive care

In December 2019, in Wuhan, a new human infectious pathology was born, COVID-19, consisting above all in pneumoniae, induced by the coronavirus named SARS-CoV-2 because of the respiratory distress it caused (SARS for severe acute respiratory syndrome, and CoV for Coronavirus). A real health and planetary crisis has appeared, much more substantial than that linked to SARS-CoV-1 in 2002-2004 and to MERS-CoV (Middle East Respiratory Syndrome Coronavirus) in 2012. In addition to respiratory damage that can be dramatic, this pathology is complicated by the frequency of cardiovascular, renal and coagulation diseases. Health care systems have had to adapt urgently, in the absence of hindsight from the patho- logy, and without effective therapeutic weapons. Through this review of the literature, we detail our local practices for the overall management of patients hospitalized in Intensive care

Cyclic appearance of left ventricular outflow tract dynamic obstruction during mechanical ventilation: evidence for a preload dependent phenomenon.

The cyclic appearance of dynamic left ventricular outflow tract obstruction during mechanical ventilation, according to the phasic changes in preload, is described in this article. Hemodialysis-induced fluid removal resulted in preload dependence as evidenced by the pulse pressure variation in a 56-year-old critically ill patient. The clinical picture was suggestive of myocardial failure. Transthoracic echocardiography disclosed dynamic left ventricular outflow tract obstruction associated with systolic anterior motion of the mitral valve. Progressive fluid restitution resulted in a parallel decrease in both the degree of dynamic obstruction and pulse pressure variation. During fluid loading, dynamic obstruction disappeared at first during the inspiratory phase of intermittent positive pressure ventilation corresponding to the phasic increase in left ventricular preload. Further fluid loading resulted in the disappearance of dynamic obstruction during both inspiratory and expiratory phase of intermittent positive pressure ventilation. This is the first reported case clearly relating left ventricular outflow tract dynamic obstruction to preload dependence during mechanical ventilation in a critically ill patient without predisposing anatomical factor