Efficacy of management for rational use of antibiotics in surgical departments at a multi-disciplinary hospital: Results of a 7-year pharmacoepidemiological research

Background. Irrational medicine use including excessive use and abuse of antibiotics remains a crucial problem for the healthcare systems. <In this regard, studies examining approaches to improving the clinical use of medicines are highly important. Aim: to assess the efficacy rate of management for the rational use of antibiotics in surgical departments of a multi-disciplinary hospital. Material and methods. The intervention complex combined the research, educational, and methodological activities: local protocols for perioperative antibiotic prophylaxis (PABP) for various surgical departments were developed; local PABP protocols were discussed with the physicians of specialized surgical departments; official order on implementation of PABP was issued; the list of drug prescriptions for registration of the first pre-operative antibiotic dose was changed; audit and feedback processes were introduced as well as consultations of a clinical pharmacologist were implemented. We assessed the efficacy rate of the interventions basing on the changes in consumption of antibiotics (both quantitatively and qualitatively) at surgical departments of a hospital using ATC/DDD methodology. Comparison of the studied outcomes was performed before and after the intervention implementation and between the departments (vascular and abdominal surgery). The consumption of antibacterial agents (ATCJ01) was measured as a number of defined daily doses (DDD) per 100 bed-days (DDD/100 bed-days, indicator recommended by the World Health Organization, WHO) and DDD per 100 treated patients (DDD/100 treated patients). Results. From 2006 to 2012, a decrease in antibacterial consumption in surgical departments by 188 DDD/100 treated patients was observed. We obtained the opposite results when using an indicator of DDD/100 bed-days (increase by 2.5 DDD/100 bed-days) which could be explained by the dependence on indices of overall hospital work and its changes during the examined period. Observed changes in antibacterial consumption varied in different surgical departments. The most pronounced positive changes were noted in the department of vascular surgery: decrease in total antibacterial consumption by 298 DDD/100 treated patients, decrease in the use of cephalosporins of the III generation from 141 to 38 DDD/100 treated patients. These positive changes were accompanied by the same (low) level of consumption/use of reserve antibiotics. In the department of abdominal surgery, there was no decrease in total antibiotic consumption, as well as in consumption of broad-spectrum cephalosporins of the III generation and fluoroquinolones, and we observed an increase in the use of reserve antibiotics (carbapenems) during the study period. Positive changes in antibiotic consumption were associated with the positive attitude of the manager/head of the department towards interventions: we observed the most pronounced decrease in antibiotic consumption straight after the publication of the administrative order on perioperative antibacterial prophylaxis. Conclusion. The combination of scientific, educational, and methodological interventions is effective for improving antibiotic application. The study results provide the rationale for analyzing the drug consumption using the DDD/100 treated patients measure in addition to the WHO-recommended indicator of DDD/100 bed-days which depends on overall hospital performance

Dynamics of the UV-Induced Absorption of Laser Light by Color Centers in Crystalline KY3F10:Ce3+,Yb3+

© 2014, Springer Science+Business Media New York. A pump-probe method is used to study the dynamics of the destruction of color centers in KY3F10:Ce3+ and KY3F10:Ce3+,Yb3+ crystals by continuous UV radiation and to measure its parameters. The effect of Yb3+ ions in crystalline KY3F10:Ce3+,Yb3+ on the rate of bleaching of color centers in it under exposure to the probe light is studied. Irradiation of KY3F10:Ce3+ and KY3F10:Ce3+,Yb3+ crystals at a wavelength corresponding to an absorption band of a color center accelerates the destruction of the color centers and the reduction of Yb2+ ions to the trivalent state in proportion to the density of the radiation. A model is constructed for the bleaching mechanism that can be used to estimate the ionization cross section of the color centers

Laser performance investigation of a new UV active media LiY 0,3Lu0,7F4:Ce3+ and LiY 0,3Lu0,7F4:Ce3++Yb3+

We show that the LiY0,3Lu0,7F4:Ce 3+ and LiY0,3Lu0,7F4:Ce 3++Yb3+ crystals are promising active media of UV spectral range with low-threshold lasing (30-90 mJ/cm2). Due to crystal-chemical approach (additional doping by ions Yb3+) we obtained the effect of suppression of spurious photodynamic processes. The active medium LiY0,3Lu0,7F4: Ce3++ Yb3+ combines properties of saturable amplifier and oscillator with small saturation energy, and promising to generate pulses of ultrashort duration in the UV spectrum. © Published under licence by IOP Publishing Ltd

Optical properties of UV-induced color centers in a KY3F 10:Ce3+ crystal

The evolution of color centers induced in a KY3F 10:Ce3+ crystal by UV radiation has been observed and interpreted. It has been revealed that, initially, the UV irradiation of the KY3F10:Ce3+ crystal induces the formation of color centers predominantly of the F-type, which, in a short time period of about ten minutes, are transformed into complex color centers of the F 2-type, as well as into impurity color centers. Based on the data obtained, a diagram of energy states of the crystal, dopant, and color centers has been constructed, on which most probable processes that are caused by electronic transitions occurring in the KYF:Ce3+ crystal after its UV irradiation have been indicated. © 2013 Pleiades Publishing, Ltd

Formation of a stable bivalent state of yb ions in na4y 6f22:Ce3+, yb3+ crystal under intense UV irradiation

The evolution dynamics of absorption spectra induced in samples of Na 4Y6F22:Ce3+, Yb3+ crystal by radiation resonant with 4f-5d transitions of Ce3+ ions was studied and analyzed. It was found that at least two types of color centers with different life times are induced in the studied crystal. It is established that the group of absorption bands in the UV spectral range that demonstrate long-term stability after excitation is caused by the 4f 13-4f 125d transitions of bivalent ytterbium ions. The sequence of processes that lead to the reduction of ytterbium ions from the trivalent to the bivalent state is proposed. © Pleiades Publishing, Ltd., 2011

Nuclear pseudoquadrupole resonance of 141Pr in Van Vleck paramagnet PrF3

Nuclear pseudoquadrupole resonance of 141Pr in Van Vleck paramagnet PrF3 has been observed in singlecrystal and micro- and nanopowder samples at a temperature of 4.2 K. The spectra of nuclear pseudoquadrupole resonance of 141Pr, as well as the spin-spin and spin-lattice relaxation parameters, have been obtained. The parameters of the nuclear spin Hamiltonian have been determined. It has been found that the parameters of the crystal electric field in nanocrystals differ strongly from those in microcrystals. © 2011 Pleiades Publishing, Ltd

Spectral-kinetic and photochemical properties of Ce3+:Na 4Y6-xYbxF22 single crystals

The spectral-kinetic characteristics of Ce3+ ions doped Na 4Y6-xYbxF22 (x=0-0.05) single crystals were studied. Ce3+ ions 5d-4f interconfigurational fluorescence quantum yield versus Yb3+ ion codopant concentration was measured. Pump-induced color center absorption spectra were studied and the efficiency of Yb3+ ions codoping antisolarant crystal-chemical technique applied to Na4Y6F22:Ce3+ was demonstrated. The optimal Yb3+ ions content from the point of view of effective tunable laser action was estimated. The obtained results allow proposing Na4Y6-xYbxF22 as a new prospective photochemically stabilized material for UV/VUV application

Microwave-Assisted Hydrothermal Synthesis and Annealing of DyF 3

The series of DyF3 nanosized samples was synthesized by the colloidal chemistry method. The microwave-assisted hydrothermal treatment was used for the first time for the modification of DyF3 nanoparticles. Transmission electron microscopy images show that the DyF3 nanoparticles have average particle size of about 16–18 nm and the size distribution becomes narrower during the microwave irradiation. The X-ray diffraction analysis shows the narrowing of the diffraction peaks versus microwave treatment time. The experimental data demonstrates restructuring of the nanoparticles and their crystal structure becomes closer to the ideal DyF3 regular structure during the microwave irradiation of colloidal solution. The defect-annealing model of the microwave-assisted hydrothermal modification process is suggested

On the interconfigurational 4f25d-4f3 VUV and UV fluorescence features of Nd3+ in LiYF4 (YLF) single crystals under F2 laser pumping

Fluorescence spectra and kinetics of LiYF4(YLF):Nd3+ single crystals pumped by an F2 pulsed discharge molecular laser at 157 nm have been obtained in the VUV and UV regions of the spectrum between 150-300 nm. With this pumping scheme some new fluorescence peaks have been observed. The high photochemical stability of this material under the above pumping scheme suggests that it can be used as an active medium for VUV tunable laser sources. ft]1|Permanent address: Kazan State University, 18 Lenin Str., 420008 Kazan, Russian Federation. © 1992