"Delirium Day": A nationwide point prevalence study of delirium in older hospitalized patients using an easy standardized diagnostic tool

Background: To date, delirium prevalence in adult acute hospital populations has been estimated generally from pooled findings of single-center studies and/or among specific patient populations. Furthermore, the number of participants in these studies has not exceeded a few hundred. To overcome these limitations, we have determined, in a multicenter study, the prevalence of delirium over a single day among a large population of patients admitted to acute and rehabilitation hospital wards in Italy. Methods: This is a point prevalence study (called "Delirium Day") including 1867 older patients (aged 65 years or more) across 108 acute and 12 rehabilitation wards in Italian hospitals. Delirium was assessed on the same day in all patients using the 4AT, a validated and briefly administered tool which does not require training. We also collected data regarding motoric subtypes of delirium, functional and nutritional status, dementia, comorbidity, medications, feeding tubes, peripheral venous and urinary catheters, and physical restraints. Results: The mean sample age was 82.0 \ub1 7.5 years (58 % female). Overall, 429 patients (22.9 %) had delirium. Hypoactive was the commonest subtype (132/344 patients, 38.5 %), followed by mixed, hyperactive, and nonmotoric delirium. The prevalence was highest in Neurology (28.5 %) and Geriatrics (24.7 %), lowest in Rehabilitation (14.0 %), and intermediate in Orthopedic (20.6 %) and Internal Medicine wards (21.4 %). In a multivariable logistic regression, age (odds ratio [OR] 1.03, 95 % confidence interval [CI] 1.01-1.05), Activities of Daily Living dependence (OR 1.19, 95 % CI 1.12-1.27), dementia (OR 3.25, 95 % CI 2.41-4.38), malnutrition (OR 2.01, 95 % CI 1.29-3.14), and use of antipsychotics (OR 2.03, 95 % CI 1.45-2.82), feeding tubes (OR 2.51, 95 % CI 1.11-5.66), peripheral venous catheters (OR 1.41, 95 % CI 1.06-1.87), urinary catheters (OR 1.73, 95 % CI 1.30-2.29), and physical restraints (OR 1.84, 95 % CI 1.40-2.40) were associated with delirium. Admission to Neurology wards was also associated with delirium (OR 2.00, 95 % CI 1.29-3.14), while admission to other settings was not. Conclusions: Delirium occurred in more than one out of five patients in acute and rehabilitation hospital wards. Prevalence was highest in Neurology and lowest in Rehabilitation divisions. The "Delirium Day" project might become a useful method to assess delirium across hospital settings and a benchmarking platform for future surveys

ELECTRON EMISSION FROM A NIOBIUM PHOTOCATHODE

Abstract We report on the experimental results of a niobium photocathode illuminated by two different wavelength lasers operating at 308 and 222nm.The output current was recorded by a fast Rogowski coil while the beam angular distributions by small Faraday cups placed in front the beam. For λ=308nm the quantum efficiencies were 1.0×10 -6 and 2.1×10 -6 for p and s-polarisation, respectively. When the 222nm light was used they were 1.6×10 -5 for p-polarisation and 5.3×10 -5 for s-polarisation. In both cases the s-polarisation got efficiency higher. The maximum output current was 1.25A, τ=10ns; this value was obtained utilising the shortest wavelength laser, 4.9 mJ and 20 kV accelerating voltage. By the electron beam angular divergence, we determined the upper limit normalised emittance. The shortest value found of upper limit emittance was 7 [π mm mrad], achieved by the spolarised radiation, at λ=308nm

ELECTRON EMISSION FROM A NIOBIUM PHOTOCATHODE

We report on the experimental results of a niobium photocathode illuminated by two different wavelength lasers operating at 308 and 222nm.The output current was recorded by a fast Rogowski coil while the beam angular distributions by small Faraday cups placed in front the beam. For λ=308nm the quantum efficiencies were 1.0×10-6 and 2.1×10-6 for p and s-polarisation, respectively. When the 222nm light was used they were 1.6×10-5 for p-polarisation and 5.3×10-5 for s-polarisation. In both cases the s-polarisation got efficiency higher. The maximum output current was 1.25A, τ=10ns; this value was obtained utilising the shortest wavelength laser, 4.9 mJ and 20 kV accelerating voltage. By the electron beam angular divergence, we determined the upper limit normalised emittance. The shortest value found of upper limit emittance was 7 [π mm mrad], achieved by the s- polarised radiation, at λ=308nm

Electron beam propagation in a space-charge regime

We report on the propagation of electron beams generated by a niobium photocathode illuminated by different wavelength excimer lasers. The cathode used was a polycrystalline disc. Its work function was 4.3 eV while the laser photon energy was 4.02 eV for the XeCl laser and 5.6 eV for the KrCl laser. The anode–cathode distance was variable as well as the saturation output current. At low accelerating voltage the beam was space charge dominated but its peak value was not limited by the Child–Langmuir calculated value. A fast shunt resistance allowed to record the electron beam generated with a fast rise time. The maximum output current was reached with the KrCl laser which provided an electron bunch containing 980 mA and 9 nC

Electron emission from niobium photocathode

We report on the experimental results of a niobium photocathode illuminated by two different wavelength lasers operating at 308 and 222nm.The output current was recorded by a fast Rogowski coil while the beam angular distributions by small Faraday cups placed in front the beam. For λ=308nm the quantum efficiencies were 1.0×10-6 and 2.1×10-6 for p and s-polarisation, respectively. When the 222nm light was used they were 1.6×10-5 for p-polarisation and 5.3×10-5 for s-polarisation. In both cases the s-polarisation got efficiency higher. The maximum output current was 1.25A, τ=10ns; this value was obtained utilising the shortest wavelength laser, 4.9 mJ and 20 kV accelerating voltage. By the electron beam angular divergence, we determined the upper limit normalised emittance. The shortest value found of upper limit emittance was 7 [π mm mrad], achieved by the s- polarised radiation, at λ=308nm

Studies of electron beams propagation in space-charge regime

We report the experimental characteristics of electron beam propagation under space-charge regime. The electron beams were generated by a Nb polycrystalline photocathode illuminated by two different excimer lasers, a XeCl ~308 nm! and a KrCl ~222 nm!. The laser photon energies were very close to the Nd work function. The cathode surface was mechanically worked in order to study the photoemission from a smooth and a rough surface. At low accelerating voltage the electron beam was dominated by the space-charge effect and its resulting pulse never clipped as predicted by the Child–Langmuir law. Instead, it presented as fast a rise time as the laser one, an intermediate zone, and a tail longer than the laser pulse one. On the other hand, under saturation regime the output current wave form was similar to the laser one. The quantum efficiency was higher for the rough cathode. It corresponded to 3.231025 and 6.731027 for the KrCl and XeCl irradiation, respectively. The maximum current value was an electron bunch containing 980 mA ~8.9 nC!, by means of 1.7 mJ KrCl laser energy and 10 kV of accelerating voltage