The role of the cardiologist in non-cardiac surgery: perioperative management features

Scop: Managementul perioperator adecvat este esențial în prevenirea complicațiilor cardiovasculare, inclusiv decesul de cauza cardiacă Material și metode: Ghidul Societății Europene de Cardiologie (ESC) pentru evaluarea cardiaca si managentul în chirurgia noncardiaca (2022) elaborat in comun cu Societatea Europeana de Anesteziologie si Terapie Intensivă (ESAIC) Rezultate: Aprecierea riscului preoperator trebuie sa țină cont de combinația multiplilor factori: pe de o parte de categoria de risc a operației (mică/intermediară/înaltă) pe de alta parte de factorii intriseci ce țin de pacient, în special vârsta, simptomele, factorii de risc cardiovasculari, precum și bolile cardiace cunoscute. Persoanele până la 65 ani fără factori de risc cardiovasculari sau boli cardiace constituite nu necesită careva evaluare preoperatorie pentru intervenții cu risc scăzut și intermediar, iar la intervențiile cu risc înalt se va efectua electrocardiograma și biomarkerii cardiaci la persoanele peste 45 ani. Pentru persoanele peste 65 ani sau cei cu factori de risc cardiovasculari si o interventie cu risc intermediar/ inalt se va efectua electrocardiograma, biomarkerii cardiaci si se va aprecia capacitatea functionala, iar pentru pacientii cu boli cardiovasculare cunoscute suplimentar se va efectua si consultatia cardiologului, la necesitate evaluare in echipa multidisciplinara. Evaluarea biomarkerilor, in special troponina postoperator depisteaza la timp infarctul miocardic postprocedural, care in 85% cazuri este silentios, fara durere tipica. Decizia continuarii medicamentelor cardiace cronice, in special anticoagulatele/antitromboticele deseori reprezinta o provocare, fiind esentiala examinarea atenta a riscul de sangerare si riscul ischemic, precum si cunoasterea deplina a istoricului medical al pacientului. Concluzii: Pregătirea preoperatorie necesita examinarea atenta a profilului clinic al pacientului si conlucrare interdisciplinara.Aim: Adequate perioperative management is essential in preventing cardiovascular complications, including cardiac death, during and after non-cardiac surgery. Material and methods: 2022 ESC Guidelines on cardiovascular assessment and management of patients undergoing non-cardiac surgery: developed by the task force for cardiovascular assessment and management of patients undergoing non-cardiac surgery of the European Society of Cardiology (ESC), endorsed by the European Society of Anaesthesiology and Intensive Care (ESAIC). Results: Cardiovascular risk assesment before non-cardiac surgery comprises a combination of multiple factors: on one hand there is the surgery risk category (low-risk, intermediate and high-risk) and on the other hand there are patient related risk factors to deal with, especially the patient's age, cardiovascular risk factors or even known cardiovascular disease. Individuals that are younger than 65 without any cardiovascular risk factors or known CVD do not need any additional investigations before a low- or intermediate risk surgery, while an ECG and cardiac biomarkers are warranted in those older than 45 before a high risk surgery. In individuals older than 65 or those with cardiovascular risk factors undergoing an intermediate or high risk surgery an ECG, cardiac biomarkers and functional capacity determination is necessary. Patients with known cardiovascular disease need a cardiology consult and sometimes a multidisciplinary team assessment. Dosing of cardiac biomarkers, especially cardiac troponins after surgery helps detect postprocedural myocardial infarction, which can be silent in 85% of cases - patients having no typical pain. Decisions concerning continuing chronic cardiac medication throughout the surgery, especially antithrombotic drugs, are usually quite challenging, as balancing bleeding and ischemic risks needs to be done after carefully studying the patient's history. Conclusion: Perioperative assessment requires a careful examination of the patient's clinical profile as well as interdisciplinary teamwork

Synthesis and Cathodoluminescence of Undoped and Cr^3^+-Doped Sodium Titanate Nanotubes and Nanoribbons

We report on the synthesis of Cr^3^+-doped sodium titanate nanotubes and nanoribbons by a hydrothermal method. The presence of dopant ions in these nanostructures was confirmed by high angle annular dark field scanning transmission electron microscopy in combination with electron energy loss spectroscopy measurements. Luminescence properties of undoped and Cr^3^+-doped sodium titanate nanotubes and nanoribbons were investigated by cathodoluminescence in the scanning electron microscope. A broad visible band in the range 1.7−2.7 eV is observed in these nanostructures. Such emission is similar to that observed in bulk anatase TiO_2 and titanate powders, and is related to TiO_6 octahedra, which is a common feature to all the samples investigated. Near-infrared emission, sometimes attributed to Ti^3^+ interstitials, is observed in bulk powders but is absent in the titanate nanotubes and nanoribbons. Incorporation of Cr^3^+ between the titanate layers of the nanostructures is revealed by the characteristic intraionic emission line at 1.791 eV. Sodium titanate nanoribbons appear to be an effective host for optically active Cr^3^+ ions, as compared with nanotubes or bulk powder

Resonant excitation of Er ion luminescence in a nanocrystalline silicon matrix

The luminescence of amorphous silicon layers either implanted with Er or co-implanted with Er and O has been studied by photoluminescence (PL) and cathodoluminescence (CL) in the scanning electron microscope. Annealing in nitrogen causes the formation of oxide species and Er-Si complexes or precipitates as well a spectral changes in the visible and infrared ranges. The main CL emission takes place in the visible range while PL spectra reveal intense visible and infrared emission. CL spectra show blue-violet, or green, emission bands whose relative intensities depend on the post-implantation annealing temperature. The PL spectra show a blue-violet band with a series of lines in the violet region related to phonon assisted transitions as well as different emission bands in the range 1200-1500 nm. The influence of the annealing-induced structural changes on the observed spectra is discussed

Charge carriers photogeneration in pentacene field effect transistors

Organic FET transistors (OFETs) were fabricated on silicon substrates using pentacene as active organic layer and gold source and drain contacts. OFETs were used as test structures in order to study carriers photogeneration effect in organic layers. Photogeneration process was induced by exposing organic layers to a laser beam with 625 nm wavelength and an applied power varying in the range 10-40 mu W. As an effect of light exposure, OFET drain current is increased by three-to-six orders of magnitude, depending on devices operation conditions and their geometry. It is suggested that both electrons and holes generated in pentacene layer contribute to current increase. We put in evidence that electrons trapped at the pentacene-dielectric interface can act as a negative biased gate, demonstrating new operating capabilities of OFETs as well as light sensing functionality

Structure and electrical behavior of silicon nanowires prepared by MACE process

We report on the structure and electrical characteristics of silicon nanowire arrays prepared by metal assisted chemical etching (MACE) method, investigated by cross-sectional scanning electron microscopy (SEM) and high resolution X-ray diffraction (HR-XRD) methods. SEM micrographs show arrays of merged parallel nanowires, with lengths of 700 nm and 1000 nm, resulted after 1.5 min and 5 min etching time, respectively. X-ray reciprocal space maps (RSMs) around Si (004) reciprocal lattice point indicate the presence of 0D structural defects rather than of extended defects. The photoluminescence spectra exhibit emission bands at 1.70 eV and 1.61 eV, with intensity significantly higher in the case of longer wires and associated with the more defected surface. The transient photoluminescence spectroscopy reveals average lifetime of 60 $\mu$s and 111 $\mu$s for the two SiNW arrays, which correlate with a larger density of defects states in the latest case. The I-V characteristics of the nanowires, show a memristive behavior with the applied voltage sweep rate in the range 5V/s - 0.32V/s. We attribute this behavior to trap states which control the carrier concentration, and model this effect using an equivalent circuit. Photogeneration processes under excitation wavelengths in visible domain, 405 nm - 650 nm, and under light intensity in the range 20 - 100 mW/cm$^2$ provided a further insight into the trap states.Comment: 23 pages 18 figure

Cathodoluminescence from nanocrystalline silicon films and porous silicon

Luminescence emission of nanocrystalline silicon films has been studied by cathodoluminescence (CL) in the scanning electron microscope. As-deposited films show a dominant band at 400 nm as well as a band centered at about 650 nm. CL spectra of porous silicon samples also show emission at 400 nm. Spectral changes induced by annealing and implantation treatments of the films suggest that the presence of nanocrystals is the origin of the observed CL

57Fe Mössbauer and x-ray magnetic circular dichroism study of magnetic compensation of the rare-earth sublattice in Nd2−xHoxFe14B compounds

12 pages, 8 figures, 3 tables.-- PACS number(s): 61.10.Ht, 76.80. y, 71.20.Lp, 75.50.BbWe present here a study of the magnetic properties of the Nd2−xHoxFe14B series. The macroscopic properties of these compounds evolve continuously from those of Nd2Fe14B to those of Ho2Fe14B as Ho gradually replaces Nd. The system shows a compensation of the rare-earth sublattice magnetization for a critical concentration, xc=0.55, that is reflected into the anomalous behavior of both macroscopic and microscopic magnetic probes. The combined analysis of magnetization, 57Fe Mössbauer spectroscopy and Fe K-edge x-ray magnetic circular dichroism (XMCD) measurements suggests that the origin of the anomalous magnetic behavior found at xc=0.55 is mainly due to the Ho sublattice. Moreover, the analysis of the Fe K-edge XMCD signals reveal the presence of a rare-earth contribution, reflecting the coupling of the rare-earth and Fe magnetic moments, which can lead to the possibility of disentangling the magnetic behavior of both Fe and R atoms using a single absorption edge.This work was partially supported by Spanish CICYTMAT2005-06806-C04-04 grant. M. A. L.-M. acknowledges a FPI grant from spanish MEC. The synchrotron radiation experiments were performed at SPring-8 (Proposal No. 2002A0153-NS2-np).Peer reviewe

Luminescence from erbium oxide grown on silicon

The luminescence properties of erbium oxide grown on crystalline and amorphous silicon substrates were studied by means of photo- and cathodoluminescence techniques. Differences in the luminescence spectra for samples grown on the two type., of substrates used are explained in terms of the different types of erbium centers formed by taking into account the substrate properties and the thermal treatments during growth. For comparison, erbium implanted and oxygen coimplanted crystalline and amorphous silicon have been also investigated by luminescence techniques. In the implanted samples, the sharp transitions from erbium ions in the visible range were quenched and the main emission corresponds to the intraionic transitions in Er3+ ions in the infrared range peaked at 1,54 mum