The clinical relevance of oliguria in the critically ill patient : Analysis of a large observational database

Funding Information: Marc Leone reports receiving consulting fees from Amomed and Aguettant; lecture fees from MSD, Pfizer, Octapharma, 3 M, Aspen, Orion; travel support from LFB; and grant support from PHRC IR and his institution. JLV is the Editor-in-Chief of Critical Care. The other authors declare that they have no relevant financial interests. Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Urine output is widely used as one of the criteria for the diagnosis and staging of acute renal failure, but few studies have specifically assessed the role of oliguria as a marker of acute renal failure or outcomes in general intensive care unit (ICU) patients. Using a large multinational database, we therefore evaluated the occurrence of oliguria (defined as a urine output 16 years) patients in the ICON audit who had a urine output measurement on the day of admission were included. To investigate the association between oliguria and mortality, we used a multilevel analysis. Results: Of the 8292 patients included, 2050 (24.7%) were oliguric during the first 24 h of admission. Patients with oliguria on admission who had at least one additional 24-h urine output recorded during their ICU stay (n = 1349) were divided into three groups: transient - oliguria resolved within 48 h after the admission day (n = 390 [28.9%]), prolonged - oliguria resolved > 48 h after the admission day (n = 141 [10.5%]), and permanent - oliguria persisting for the whole ICU stay or again present at the end of the ICU stay (n = 818 [60.6%]). ICU and hospital mortality rates were higher in patients with oliguria than in those without, except for patients with transient oliguria who had significantly lower mortality rates than non-oliguric patients. In multilevel analysis, the need for RRT was associated with a significantly higher risk of death (OR = 1.51 [95% CI 1.19-1.91], p = 0.001), but the presence of oliguria on admission was not (OR = 1.14 [95% CI 0.97-1.34], p = 0.103). Conclusions: Oliguria is common in ICU patients and may have a relatively benign nature if only transient. The duration of oliguria and need for RRT are associated with worse outcome.publishersversionPeer reviewe

Use of the Genetic Algorithm for the Optimal Operation of Multi-Reservoirs on Demand Irrigation System

This study presents the application of a Genetic Algorithm (GA) model developed for computation of the optimal supply hydrographs in on demand irrigation systems aimed at the optimal regulation of the upstream storage reservoirs. The model was applied to an Italian irrigation scheme whe re the optimal inflows to five reservoirs were computed. The obtained result is characteris ed by two inflow values. In addition, the maximum discharge supplied by the upstream dam was redu ced by 10.65 %, and the maximum violation of reservoirs water levels was reduced to acceptable values. The optimal solution guarantees to satisfy the daily demand requirements, to minimize the maximum discharge delivered by the upstream dam, and to avoi d the reservoirs emptiness. In addition, the on- demand delivery schedule according to the actual demand hydrograph recorded downstream the reservoirs may be applied also during the peak periodCette \uc8tude pr\uc8sente l\uedapplication d\uedun Algorithme G\uc8n\uc8 tique (AG) d\uc8velopp\uc8 pour le calcul des hydrogrammes d'approvisionnement optimaux dans les syst\ucbmes d\uedirrigation \u2021 la demande vis\uc8 pour la r\uc8gulation optimale des r\uc8servoirs de stockage. Le mod\ucble a \uc8t\uc8 appliqu\uc8 pour un r\uc8seau d\uedirrigation italien o \u306 les apports optimaux \u2021 cinq r\uc8servoirs ont \uc8t\uc8 calcul\uc8s. Le r\uc8sultat obtenu est caract\uc8ris \uc8 par deux valeurs d\uedapports. En addition, le d\uc8bit maximal fourni par le barrage en amont a \uc8t\uc8 r\uc8duit par 10.65 %, et les violations maximales des niveaux d'eau de r\uc8servoirs ont \uc8t\uc8 r\uc8duites \u2021 des valeurs accepta bles. La solution optimale garantit de satisfaire les besoins jou rnaliers, de minimiser le d\uc8bit maximal de barrage en amont et d\ued\uc8viter la vidange des r\uc8se rvoirs. En outre, la livraison \u2021 la demande selon l'hydrogramme de la demande actuelle enregistr\uc8e en aval des r\uc8servoirs peut-\ucdtre \uc8galement appliqu\uc8s pendant la p\uc8riode de pointe

The genetic algorithm approach for identifying the optimal operation of a multi-reservoirs on-demand irrigation system

A stochastic methodology, based on real-coded genetic algorithms for optimising the operation of reservoirs in an on-demand irrigation system, is presented. The methodology analyzes the adequacy of the difference between supply and demand taking into account the storage capacity of the reservoirs. It determines adequate inflow hydrographs to ensure the optimal regulation of reservoirs during the peak demand period. To take into account the variability of farmers' requirements, demand hydrographs were randomly generated within a pre-determined confidence interval. A weighted objective function, including violations of the admissible reservoir water levels (maximum, minimum and target water levels), is proposed. To solve the optimisation problem, a computer program was developed. The model was applied and tested on the Sinistra Ofanto irrigation scheme (Foggia, Italy), comprising five reservoirs fed with water from an upstream dam, each of them serving different irrigation districts. Results show that the model is efficient and robust

Effect of boron addition on structural and magnetic properties of nanostructured Fe75Al25 alloy prepared by high energy ball milling

In the present work, the effect of boron addition on microstructural and magnetic properties of (Fe75Al25)(100-x)B-x (x=0, 5, 9 and 12 at%) alloys prepared by mechanical alloying process, were investigated by X-ray diffraction and vibrating sample magnetometer and SQUID techniques. The micro structural parameters such as the crystallite size, the microstrain and the lattice parameters of the bccsolid solution Fe(Al) were deduced from the Rietveld refinement of the X-ray diffraction patterns using the X-Pert HighScore. It is found that boron additions delay the formation of the BCC-Fe(Al) solid solution by mechanical alloying. The coercivity (H-c) decreases with increasing the amount of boron added. The undoped sample showed a hard ferromagnetic behavior (Hc similar to 750 Oe) whereas the doped ones reached a softening ferromagnetic behavior (Hc < 100 Oe)