Long-term trends in critical care admissions in Wales

As national populations age, demands on critical care services are expected to increase. In many healthcare settings, longitudinal trends indicate rising numbers and proportions of patients admitted to ICU who are older; elsewhere, including some parts of the UK, a decrease has raised concerns with regard to rationing according to age. Our aim was to investigate admission trends in Wales, where critical care capacity has not risen in the last decade. We used the Secure Anonymised Information Linkage Databank to identify and characterise critical care admissions in patients aged ≥ 18 years from 1 January 2008 to 31 December 2017. We categorised 85,629 ICU admissions as youngest (18-64 years), older (65-79 years) and oldest (≥ 80 years). The oldest group accounted for 15% of admissions, the older age group 39% and the youngest group 46%. Relative to the national population, the incidence of admission rates per 10,000 population in the oldest group decreased significantly over the study period from 91.5/10,000 in 2008 to 77.5/10,000 (a relative decrease of 15%), and among the older group from 89.2/10,000 in 2008 to 75.3/10,000 in 2017 (a relative decrease of 16%). We observed significant decreases in admissions with high comorbidity (modified Charlson comorbidity index); increases in the proportion of older patients admitted who were considered 'fit' rather than frail (electronic frailty index); and decreases in admissions with a medical diagnosis. In contrast to other healthcare settings, capacity constraints and surgical imperatives appear to have contributed to a relative exclusion of older patients presenting with acute medical illness.

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine: Brussels, Belgium. 15-18 March 2016

[This corrects the article DOI: 10.1186/s13054-016-1208-6.].

Differential interference contrast microscopy using light-emitting diode illumination in conjunction with dual optical traps

Differential interference contrast (DIC) microscopy is a common mode of biological light microscopy used to achieve maximal resolution and contrast with label-free, weakly absorbing specimens such as cells. Maintaining the polarization state of the illuminating light is essential for the technique, and this requirement can conflict with optical trapping. We describe how to optimize DIC imaging using a light-emitting diode illumination source in a microscope while integrating a dual optical trap into the set up. Every time a polarized light beam reflects off or transmits through a dichroic mirror in the beam path, its polarization state will change if it is not polarized exactly parallel (p) or perpendicular (s) to the plane of incidence. We observe wavelength-dependent optical rotation and depolarization effects in our illumination light upon reflection from/transmission through dichroic mirrors in the beam path, resulting in significant degradation of image quality. We describe a method to compensate for these effects by introducing quarter-waveplates and a laser clean-up filter into the imaging pathway. We show that this approach achieves a full recovery of image quality.

Unraveling DNA tori under tension

Motivated by recent experiments, we develop a model for DNA toroids under external tension. We find that tori are the equilibrium states for our model up to a critical tension, above which they become only metastable. Above this tension, we find a cascade of transitions between discrete toroid states that successively lower the winding number, until the ground state (rod) is reached. In this process, this model predicts a nearly constant force plateau as a function of extension, in agreement with experiment.

Search for new heavy particles in the WZ0 final state in pp collisions at square root[s] = 1.8 TeV

We present the first general search for new heavy particles, X, which decay via X --> WZ0 --> e(nu)+jj as a function of M(X) and Gamma(X) in pp collisions at square root[s] = 1.8 TeV. No evidence is found for production of X in 110 pb(-1) of data collected by the Collider Detector at Fermilab. General cross section limits are set at the 95% C.L. as a function of mass and width of the new particle. The results are further interpreted as mass limits on the production of new heavy charged vector bosons which decay via W' --> WZ0 in an extended gauge model as a function of the width, Gamma(W'), and mixing factor between the W' and the standard model W bosons.

Clozapine eligibility: the effect of stringent criteria on ethnic, gender and age subgroups of schizophrenic patients

1. The purpose of this retrospective chart review study was to determine whether broad and stringent criteria differentially impact clozapine eligibility in ethnic, gender, and age subgroups of schizophrenic patients. 2. 505 patients charts were selected from a random cluster sample of mental health patients known to the city and county of San Francisco. Information related to clozapine eligibility was abstracted by trained non-clinical personnel. The impact of subgroup membership on eligibility was examined using logistic regression procedures. 3. Even under the broadest interpretation of FDA requirements for clozapine use, Asian patients were less likely to be eligible, since fewer Asian patients met clozapine treatment requirements. Under more stringent eligibility criteria, older patients were more likely to be excluded from eligibility when TD does not automatically satisfy treatment criteria, and younger patients were more likely to lose eligibility if the number of required adequate medication trials increases to three. 4. Broad eligibility criteria tend to differentially exclude Asian patients while more stringent criteria differentially exclude younger and older patients.

Effects of stringent criteria on eligibility for clozapine among public mental health clients

OBJECTIVE

This study estimated rates of eligibility for treatment with clozapine among clients in a public mental health system using criteria with various degrees of restrictiveness.

METHODS

A stratified, random cluster sample of 293 clients was selected from among all clients with schizophrenic disorders known to the mental health system of the city and county of San Francisco during 1991. Data on variables associated with eligibility for clozapine were abstracted from clinical records, and eligibility was estimated using broad and stringent criteria.

RESULTS

An estimated 42.9 percent of the clients were eligible for clozapine using broad eligibility criteria that included a diagnosis of schizophrenia or schizoaffective disorder, two previous neuroleptic trials of at least 600 mg per day chlorpromazine equivalents for at least four weeks or tardive dyskinesia, Global Assessment of Functioning score less than 61, and no contraindications. Eliminating eligibility due to tardive dyskinesia alone, excluding persons with schizoaffective disorder, requiring six-week medication trials, and requiring three adequate medication trials instead of two resulted in substantial reductions in the rate of eligibility.

CONCLUSIONS

Varying interpretations of the criteria for clozapine treatment listed in the medication package insert dramatically affect patients' eligibility for clozapine. Mental health agencies should endeavor to maintain a balance between restricting use of clozapine due to cost and providing it to the full spectrum of patients who might benefit from the medication.