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To quantify the frequency and outcomes of receiving an antibiotic prescription upon discharge from the hospital to long-term care facilities (LTCFs).
Retrospective cohort study.
A 576-bed, academic hospital in Portland, Oregon.
Adult inpatients (≥18 years of age) discharged to an LTCF between January 1, 2012, and June 30, 2016.
Our primary outcome was receiving a systemic antibiotic prescription upon discharge to an LTCF. We also quantified the association between receiving an antibiotic prescription and 30-day hospital readmission, 30-day emergency department (ED) visit, and Clostridium difficile infection (CDI) on a readmission or ED visit at the index facility within 60 days of discharge.
Among 6,701 discharges to an LTCF, 22.9% were prescribed antibiotics upon discharge. The most prevalent antibiotic classes prescribed were cephalosporins (20.4%), fluoroquinolones (19.1%), and penicillins (16.7%). The medical records of ~82% of patients included a diagnosis code for a bacterial infection on the index admission. Among patients prescribed an antibiotic upon discharge, the incidence of 30-day hospital readmission to the index facility was 15.9%, the incidence of 30-day ED visit at the index facility was 11.0%, and the incidence of CDI on a readmission or ED visit within 60 days of discharge was 1.6%. Receiving an antibiotic prescription upon discharge was significantly associated with 30-day ED visits (adjusted odds ratio [aOR], 1.2; 95% confidence interval [CI], 1.02–1.5) and with CDI within 60 days (aOR, 1.7; 95% CI, 1.02–2.8) but not with 30-day readmissions (aOR, 1.01; 95% CI, 0.9–1.2).
Antibiotics were frequently prescribed upon discharge to LTCFs, which may be associated with increased risk of poor outcomes post discharge.
Our knowledge of the universe comes from recording the photon and particle fluxes incident on the Earth from space. We thus require sensitive measurement across the entire energy spectrum, using large telescopes with efficient instrumentation located on superb sites. Technological advances and engineering constraints are nearing the point where we are recording as many photons arriving at a site as is possible. Major advances in the future will come from improving the quality of the site. The ultimate site is, of course, beyond the Earth’s atmosphere, such as on the Moon, but economic limitations prevent our exploiting this avenue to the degree that the scientific community desires. Here we describe an alternative, which offers many of the advantages of space for a fraction of the cost: the Antarctic Plateau.
The M supergiants are rare objects in the solar neighbourhood and consequently until recently their importance has been largely overlooked. It is now being realized that these stars hold the key to extragalactic distance determinations since they can be detected at large distances while the maximum luminosity they attain seems to be remarkably constant and independent of galaxy type (Sandage and Tammann 1974; Humphreys 1978, 1979a, 1979b; Humphreys and Davidson 1979). They are also important in their own right since they are massive stars in the late stages of their evolution and undoubtedly suffer from mass loss and chemical enrichment due to the mixing of processed materials to their surfaces. In this light they can be considered as precursors of the luminous carbon stars and supernovae.
To quantify the association between admission to an intensive care unit (ICU) room most recently occupied by a patient positive for extended-spectrum β-lactamase (EBSL)-producing gram-negative bacteria and acquisition of infection or colonization with that pathogen.
Retrospective cohort study.
Setting and Patients.
The study included patients admitted to medical and surgical ICUs of an academic medical center between September 1, 2001, and June 30, 2009.
Perianal surveillance cultures were obtained at admission to the ICU, weekly, and at discharge from the ICU. Patients were included if they had culture results that were negative for ESBL-producing gram-negative bacteria at ICU admission and had an ICU length of stay longer than 48 hours. Pulsed-field gel electrophoresis (PFGE) was performed on ESBL-positive isolates from patients who acquired the same bacterial species (eg, Klebsiella species or Escherichia coli) as the previous room occupant.
Among 9, 371 eligible admissions (7, 651 unique patients), 267 (3%) involved patients who acquired an ESBL-producing pathogen in the ICU; of these patients, 32 (12%) were hospitalized in a room in which the prior occupant had been positive for ESBL. Logistic regression results suggested that the prior occupant's ESBL status was not significantly associated with acquisition of an ESBL-producing pathogen (adjusted odds ratio, 1.39 [95% confidence interval, 0.94-2.08]) after adjusting for colonization pressure and antibiotic exposure in the ICU. PFGE results suggested that 6 (18%) of 32 patients acquired a bacterial strain that was the same as or closely related to the strain obtained from the prior occupant.
These data suggest that environmental contamination may not play a substantial role in the transmission of ESBL-producing pathogens among ICU patients. Intensifying environmental decontamination may be less effective than other interventions in preventing transmission of ESBL-producing pathogens.
Risk factors for development of intestinal colonization by imipenem-resistant Pseudomonas aeruginosa (IRPA) may differ between those who acquire the organism via patient-to-patient transmission versus by antibiotic selective pressure. The aim of this study was to quantify potential risk factors for the development of IRPA not due to patient-to-patient transmission.
Colonization pressure is an important infection control metric. The aim of this study was to describe the definition and measurement of and adjustment for colonization pressure in nosocomial-acquisition risk factor studies of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and Clostridium difficile.
We performed a computerized search of studies of nosocomial MRSA, VRE, and C. difficile acquisition published before July 1, 2009, through MEDLINE. Studies were included if a study outcome was MRSA, VRE, or C. difficile acquisition; the authors identified risk factors associated with MRSA, VRE, or C. difficile acquisition; and the study measured colonization pressure.
The initial MEDLINE search yielded 505 articles. Sixty-six of these were identified as studies of nosocomial MRSA, VRE, or C. difficile acquisition; of these, 18 (27%) measured colonization pressure and were included in the final review. The definition of colonization pressure varied considerably between studies: the proportion of MRSA- or VRE-positive patients (5 studies), the proportion of MRSA- or VRE-positive patient-days (6 studies), or the total or mean number of MRSA-, VRE-, or C. difficile-positive patients or patient-days (7 studies) in the unit over periods of varying length. In 10 of 13 studies, colonization pressure was independently associated with MRSA, VRE, or C. difficile acquisition.
There is a need for a simple and consistent method to quantify colonization pressure in both research and routine clinical care to accurately assess the effect of colonization pressure on cross-transmission of antibiotic-resistant bacteria.
Recognition of seasonal trends in hospital infections may improve diagnosis, use of empirical therapy, and infection prevention interventions. There are very few data available regarding the seasonal variability of these infections. We quantified the seasonal variation in the incidences of hospital infection caused by common bacterial pathogens and estimated the association between temperature changes and infection rates.
A cohort of all adult patients admitted to the University of Maryland Medical Center during the period from 1998 through 2005 was analyzed. Time-series analyses were used to estimate the association of the number of infections per month caused by Pseudomonas aeruginosa, Acinetobacter baumannii, Enterobacter cloacae, Escherichia coli, Staphylococcus aureus, and enterococci with season and temperature, while controlling for long-term trends.
There were 218,594 admissions to the index hospital, and analysis of 26,624 unique clinical cultures that grew the organisms of interest identified increases in the mean monthly rates of infection caused by P. aeruginosa (28% of isolates recovered; P < .01), E. cloacae (46%; P < .01), E. coli (12%; P < .01), and A. baumannii (21%; P = .06). For each 10°F increase, we observed a 17% increase in the monthly rates of infection caused by P. aeruginosa (P = .01) and A. baumanii (P = .05).
Significantly higher rates of gram-negative infection were observed during the summer months, compared with other seasons. For some pathogens, higher temperatures were associated with higher infection rates, independent of seasonality. These findings have important implications for infection prevention, such as enhanced surveillance during the warmer months, and for choice of empirical antimicrobial therapy among hospitalized adults. Future, quasi-experimental investigations of gram-negative infection prevention initiatives should control for seasonal variation.
Probability theory abounds in counterintuitive results, perhaps the most celebrated being the answer to the birthday problem: what is the least value of n such that p (n, 2) > ½ where p (n, 2) denotes the probability that at least two out of n randomly chosen people have the same birthday? The question assumes birthdays are uniformly and independently distributed with leap years being ignored. The solution, n = 23, never fails to startle beginning students, and very often triggers an interest in the subject of probability. It is derived from the well-known observation that by the principle of complementation p (n, 2) is one minus the probability that no two have the same birthday, i.e.
The effect of point defect injection on the diffusion of antimony and boron in silicon and silicon-germanium alloys has been studied by comparison of inert with injection diffusions. In this work, Sb and B in Si were used as control wafers to investigate Sb and B diffusion behavior in Si0.9Ge0.1. The point defect injection technique was carried out by rapid thermal annealing (RTA) Sb and B in Si and Si0.9Ge0.1 samples with the various surface coatings in either oxygen or ammonia atmospheres to inject either interstitial or vacancy defects. The diffusion profiles for as-grown and RTA annealed samples were measured by Secondary Ion Mass Spectrometry (SIMS). Diffusivities for B in Si and Si0.9Ge0.1 were obtained using computer simulations of the measured boron profiles for their annealed samples. Sb diffusion in Si and Si0.9Ge0.1 was found enhanced by vacancy injection and retarded by interstitial injection. The enhanced B diffusion in Si and Si0.9Ge0.1 was found by interstitial injection. These results confirm that Sb diffusion in Si0.9Ge0.1 is primarily dominated by vacancy-mediated mechanism, while B diffuses in Si0.9Ge0.1 by an interstitially mediated mechanism. The effect of the RTA diffusion time on the B diffusion in Si and Si0.9Ge0.1 has also been investigated. The diffusivity versus diffusion time of B in Si and Si0.9Ge0.1 for inert and injection samples is presented. It was found that the shorter annealing time had the faster diffusion. This suggested that it caused by transient diffusion effect arising from point defects.
Wing feather mite burdens on seven species of passerine birds (Carduelis carduelis – goldfinch; C. chloris – greenfinch; Serinus serinus – serin; Sylvia atricapilla – blackcap; Sylvia melanocephala – Sardinian warbler; Turdus merula – blackbird; Passer domesticus – house sparrow) from Portugal were assessed by the subjective semi-quantitative scoring system of Behnke et al. (1995) in order to evaluate more fully the accuracy and reliability of the technique. Our analysis indicated that in all species, scores allocated to flight feathers showed a significant positive relationship with mite counts as assessed through microscopical examination of the same feathers. However, there were differences between species of birds. Of the species examined, goldfinches and greenfinches showed the weakest relationships between assigned mite scores and actual mite numbers indicating that the technique was less accurate when applied to these species compared with the remaining five. No evidence was found that anything more was to be gained from scoring both wings, rather than just one. Feather mites (Proctophyllodes spp., Trouessartia incisa) were also detected on tail feathers, but the assessment of these feathers presented additional problems and it was concluded that in the interests of minimizing handling time of birds, tail scores had little more to offer. We conclude that scoring all the flight feathers (including all primary, secondary, and tertiary feathers) on one entire wing, but alternating between left and right wings of birds within a species, represents an acceptable compromise between sufficiently detailed examination and minimization of bird handling time in the field.
The results of a 5 year study of helminth parasites of Mus spretus, are reported. Six nematode and 5 cestode species were identified but no helminth showed 100% prevalence in M. spretus, the most commonly encountered nematode and cestode species being Syphacia obvelata (46·6%) and Taenia taeniaeformis (22·4%). Among the more unusual helminth species identified was Eucoleus bacillatus, a capillariid nematode inhabiting the stomach musculature. This species was identified in 3 of the 5 years of the study. The results are discussed in the broader context of previous studies and the epidemiology of rodent helminth infections in general.
The paper examines the results of an experiment which was designed to elucidate the manner in which wave characteristics, strut geometry and aspect ratio influence the angles at which struts ventilate. The experiment was conducted using small-scale models in a towing tank which allowed the wave parameters to be varied independently. The results indicate which parameters of a seaway are most hazardous to the operation of a hydrofoil ship in high seas and suggest design features which may extend the capability range of such craft.
In 1899 Kaplan described the “explosive diathesis” as follows: “Following the most trivial and impersonal causes, there is the effect of rage with its motor accompaniments. There may be the most grotesque gesticulation, excessive movements of the face, and a quick, sharp explosiveness of speech; there may be cursing and outbreaks of violence, which are often directed towards things; there may or may not be an amnesia for these afterwards. These outbursts may terminate in an epileptic fit. There is an excess in the reaction, with inadequate adaptation to the situation so remote from a well-considered purposeful act that it approaches a pure psychic reflex act in the shape of an almost or entirely unmodified explosion not unlike a convulsion. The explosive diathesis is not characteristic of head injuries, but is also found in hereditary degeneration, in alcoholic degeneration, etc.”
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