Readmissions - can they be predicted on admission?

This paper looks at the development of logistic regression models to predict readmissions for medical patients on their initial admission to hospital. The design of our study was a retrospective analysis of a large dataset drawn from a range of secondary sources - medical, nursing, therapy and social care records. Three northern hospitals and related community health districts and social care organizations in the UK participated. Records of 1,192 patients discharged from medical wards during the period April 1992-March 1995 were analysed. Readmission within six weeks of discharge was the main outcome measure.Four logistic regression equations were produced. Three individual site equations were calculated and classification levels for readmission of 17-22 per cent were achieved. Component factors that differed in importance were age, GP contact, social services contact, marital status and living status. The weakest equation was the equation that encompassed patients from all three sites, which classified 7 per cent of readmissions. It is possible to develop equations that will explain readmission for a fifth of medical patients on admission to individual hospitals. Further exploratory work needs to be undertaken to explore reasons for differences between districts and develop more generalizable predictive equations.

Evidence-based Standardized Care Plans for Use Internationally to Improve Home Care Practice and Population Health

OBJECTIVES

To develop evidence-based standardized care plans (EB-SCP) for use internationally to improve home care practice and population health.

METHODS

A clinical-expert and scholarly method consisting of clinical experts recruitment, identification of health concerns, literature reviews, development of EB-SCPs using the Omaha System, a public comment period, revisions and consensus.

RESULTS

Clinical experts from Canada, the Netherlands, New Zealand, and the United States participated in the project, together with University of Minnesota School of Nursing graduate students and faculty researchers. Twelve Omaha System problems were selected by the participating agencies as a basic home care assessment that should be used for all elderly and disabled patients. Interventions based on the literature and clinical expertise were compiled into EB-SCPs, and reviewed by the group. The EB-SCPs were revised and posted on-line for public comment; revised again, then approved in a public meeting by the participants. The EB-SCPs are posted on-line for international dissemination.

CONCLUSIONS

Home care EB-SCPs were successfully developed and published on-line. They provide a shared standard for use in practice and future home care research. This process is an exemplar for development of evidence-based practice standards to be used for assessment and documentation to support global population health and research.

Laryngeal manifestations of haemochromatosis

We present a case with sudden onset of throat pain, dysphagia and hoarseness. On endoscopic examination, supraglottic swelling and a brown covering of the mucous membranes were seen. The diagnosis of haemochromatosis was made on laryngeal biopsy. The patient admitted to long-term iron treatment for anaemia. Haemochromatosis can affect many different organs. If the larynx is involved, the airway may be endangered.

Comparison of cerebral pharmacokinetics of buprenorphine and norbuprenorphine in anin vivosheep model

The pharmacokinetics and time course of blood-brain equilibration of buprenorphine (BUP) and norbuprenorphine (norBUP) in sheep were characterized. Sheep were administered 0.04 mg kg(-1) BUP or 0.6 mg kg(-1) norBUP as 4-min i.v. infusions. The cerebral kinetics were inferred from arterio-sagittal sinus concentration gradients and changes in cerebral blood flow. These data were fitted to physiologically based pharmacokinetic models. BUP cerebral kinetics were best described by a membrane-limited model with a large equilibration delay (half-life of 20 min) between brain and blood due to intermediate permeability (47 ml min(-1)) and a large cerebral distribution volume (595 ml). Significant limitation in permeability (6 ml min(-1)) characterized the cerebral kinetics of norBUP with a cerebral distribution volume (157 ml) giving a blood-brain equilibration half-life (21 min) similar to that for BUP. The logD of BUP and norBUP were 3.93 +/- 0.08 and 1.18 +/- 0.04 (mean +/- SD), respectively. Both compounds revealed slow cerebral equilibration with variations in degree of permeability and distribution volume reflecting the difference in lipophilicity. It is possible that norBUP contributes to the central effects seen after chronic BUP administration as this study demonstrated its entry into the brain.

Molecular subtyping of mastitis-associated Klebsiella pneumoniae isolates shows high levels of diversity within and between dairy herds

Despite advances in controlling mastitis (inflammation of the mammary gland), udder infections caused by Klebsiella pneumoniae continue to affect dairy cattle. Mastitis caused by K. pneumoniae responds poorly to antibiotic treatment, and as a consequence, infections tend to be severe and long lasting. We sought to determine whether a nonrandom distribution of specific genotypes of K. pneumoniae was associated with mastitis from 6 dairy herds located in 4 different states. A total of 635 isolates were obtained and fingerprinted by repetitive DNA sequence PCR. Significant genetic diversity was observed in 4 of the 6 dairy herds analyzed, and a total of 49 genotypic variants were identified. Within a herd, Simpson's diversity indices were 91.0, 94.1, 91.7, 88.6, 53.3, and 64.3% for dairies A, B, C, D, E, and F, respectively. The association between matrices of genetic similarity and matrices of temporal distance was negative in all the dairies analyzed. Four dairies had a high incidence of K. pneumoniae mastitis during the winter. The majority of genotypes were unique to herds of origin, and only 5 genotypes were detected in more than 2 dairies. Genotype 1 (arbitrary designation) occurred most frequently across dairies and was found in 25.2% of all mastitis cases and among 22.8% of reinfected and culled cows in dairy A. Specific genotypes also tended to be associated with a specific bedding type and dairy location. Analysis of molecular variance showed that 18% of the genetic diversity was due to variation among herds within states, and 82% of the genetic diversity was accounted for by variation of genotypes within herds. The data support the idea that mastitis is caused by a diverse group of K. pneumoniae genotypes and thus has major implications for the diagnosis, prevention, and treatment of udder infections in dairy cows.

Genetic diversity of mastitis-associated Klebsiella pneumoniae in dairy cows

The objectives of this study were to determine the level of genetic diversity of Klebsiella pneumoniae isolated from clinical mastitis cases and to define genotypes most commonly associated with the disease. Individual quarter milk samples were collected from a single privately owned dairy herd over a 2-yr period and submitted to the Laboratory for Udder Health, Minnesota Veterinary Diagnostic Laboratory, University of Minnesota, for bacteriological culture. Eighty-four K. pneumoniae isolates were obtained and fingerprinted by repetitive DNA sequence PCR, 43 by pulsed-field gel electrophoresis (PFGE), and 29 by multilocus sequence typing (MLST). Significant genetic diversity was observed among the isolates regardless of the fingerprinting method used. Simpson's diversity index was 93.5, 96.1, and 97.0% when analyzed by repetitive DNA sequence PCR (n = 84), pulse field gel electrophoresis (n = 43), and MLST (n = 29), respectively. In some cases more than 1 genotype was obtained from a single milk sample originating from an individual quarter. The majority of infections were observed during the winter and accounted for 69.0% of K. pneumoniae mastitis cases. There was a negative correlation between a matrix of fingerprints similarity and a matrix of temporal distances. The MLST results revealed 5 new and novel allelic types, which have not been previously reported in the MLST database. Three isolates shared MLST types with human clinical isolates, raising the possibility that some K. pneumoniae isolates, of bovine origin, may be capable of causing disease in humans. There were 21 genotypes present within the herd, and there was no evidence for nonrandom distribution of genotypes uniquely associated with mastitis. We have shown, using 3 distinct genotyping methods, that K. pneumoniae isolated from clinical mastitis within a single dairy herd is caused by a genetically diverse population and that multiple genotypes can be isolated from a mastitic quarter. The data suggest that mastitis can be caused by a variety of K. pneumoniae genotypes. Diverse genotypes may have different levels of invasiveness and virulence and may originate from various sources within the dairy.

Nocardia infections in cats: a retrospective multi-institutional study of 17 cases

OBJECTIVE

To record 17 cases of nocardiosis in cats from eastern Australia and to compare this series with cases previously reported.

DESIGN

Retrospective/prospective study.

RESULTS

Nocardia spp infections were diagnosed in 17 cats over 14 years from the three eastern states of Australia. There were no isolates from dogs during this period, but one isolate from a koala and two from dairy cows. The majority of cats presented with spreading lesions of the subcutis and skin associated with draining sinus tract(s). Early cutaneous lesions consisted of circumscribed abscesses. Infections spread at a variable rate, generally by extension to adjacent tissues. Lesions were generally located in regions subjected to cat bite or scratch injuries, including limbs, body wall, inguinal panniculus and nasal bridge. In some other cases, lesions were situated on distal extremities. The clinical course was variable, from chronic, indolent, initially localised infections to acute fulminating disease. Of the 17 cats, 14 were domestic crossbreds and three were purebreds. There was a preponderance of male cats (12 castrated, 1 entire young adult, 1 entire kitten). Nine of 17 cats were 10 years or older. Interestingly, the majority of infections were attributable to N nova. Immediate and/or predisposing causes could be identified in all cases, and included: renal transplantation [one cat]; chronic corticosteroid administration [three cats]; catabolic state following chylothorax surgery [one cat]; fight injuries [seven cats]; FIV infections [three of seven cats tested]. Of the 17 cats, three were apparently cured. Four were thought to be cured, but infection recurred after several months. Three cats responded partially but were euthanased, while another was improving when it died of unrelated complications. Two died despite treatment and two were euthanased without an attempt at therapy. For two cats there were either insufficient records or the patient was lost to follow up.

CONCLUSION

Nocardiosis is a rare, serious disease. Currently it is more common in cats than dogs. Nocardial panniculitis may be clinically indistinguishable from the syndrome caused by rapidly growing mycobacteria. Although the prognosis is guarded, patients with localised infections caused by N nova often respond to appropriate therapy. If definitive treatment is delayed because of misdiagnosis, the disease tends to become chronic, extensive and refractory. Insufficient duration of therapy leads to disease recurrence.

Downregulation of N1 gene expression inhibits the initial heartbeating and heart development in axolotls

Recessive mutant gene c in the axolotl results in a failure of affected embryos to develop contracting hearts. This abnormality can be corrected by treating the mutant heart with RNA isolated from normal anterior endoderm or from endoderm conditioned medium. A cDNA library was constructed from the total conditioned medium RNA using a random priming technique in a pcDNAII vector. We have previously identified a clone (designated as N1) from the constructed axolotl cDNA library, which has a unique nucleotide sequence. We have also discovered that the N1 gene product is related to heart development in the Mexican axolotl [Cell Mol. Biol. Res. 41 (1995) 117]. In the present studies, we further investigate the role of N1 on heartbeating and heart development in axolotls. N1 mRNA expression has been determined by using semi-quantitative RT-PCR with specifically designed primers. Normal embryonic hearts (at stages 30-31) have been transfected with anti-sense oligonucleotides against N1 to determine if downregulation of N1 gene expression has any effect on normal heart development. Our results show that cardiac N1 mRNA expression is partially blocked in the hearts transfected with anti-sense nucleotides and the downregulation of N1 gene expression results in a decrease of heartbeating in normal embryos, although the hearts remain alive as indicated by calcium spike movement throughout the hearts. Confocal microscopy data indicate some myofibril disorganization in the hearts transfected with the anti-sense N1 oligonucleotides. Interestingly, we also find that N1 gene expression is significantly decreased in the mutant axolotl hearts. Our results suggest that N1 is a novel gene in Mexican axolotls and it probably plays an important role in myofibrillogenesis and in the initiation of heartbeating during heart development.