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OBJECTIVE: The British National Service Framework (NSF) for heart disease commended the 'Utstein style' for auditing out-of-hospital cardiac arrests. The NSF also set standards for pre-hospital treatment and response times. To increase the flexibility of Utstein, an 'event tree' technique is proposed as an audit tool. Event trees consist of nodes and branches on which numbers, percentages or probability values are entered. METHODS: Using the London Ambulance Service's (LAS) 1997 database on 3,759 out-of-hospital cardiac arrests, 2,772 arrests witnessed by lay bystanders or unwitnessed were analysed focusing on bystander cardiopulmonary resuscitation (BCPR) and response times. RESULTS: The Utstein template showed that witnessed arrests in ventricular fibrillation (VF) or ventricular tachycardia (VT) who had received BCPR achieved a return of spontaneous circulation (ROSC) in the field significantly more often than non-BCPR recipients-26 versus 16% (P=0.006). But the likelihood of being admitted to a hospital bed, and discharged alive, was only marginally better for BCPR recipients. To examine the influence of BCPR on the presenting rhythm an event tree showed that in 48% of witnessed BCPR cases the presenting rhythm was VF/VT, whereas, for witnessed non-BCPR cases, 27% were in VF/VT (P<0.0001). With unwitnessed arrests, 31% of BCPR cases were in VF/VT compared with 18% for non-BCPR cases (P<0.0001). Call to scene time was less than 8 min for 66% of all VF/VT arrests. CONCLUSION: The event trees, when combined with the Utstein template, demonstrated the importance of examining comprehensively datasets for both witnessed and unwitnessed cardiac arrests when monitoring performance standards. The analyses also emphasised the relevance of community programmes in Greater London for teaching basic life saving skills.  相似文献   
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Objective:

To describe the theory and methodology of the multi-wave, prospective Maternal Adversity, Vulnerability and Neurodevelopment (MAVAN) study. The goal of MAVAN is to examine the pre- and postnatal influences, and their interaction, in determining individual differences in mental health.

Method:

MAVAN is a community-based, birth cohort study of pregnant Canadian mothers and their offspring. Dyads are assessed longitudinally, with multiple assessments of both mother and child in home and laboratory across the child’s development. Study measures, including assessments of cognitive and emotional function, are described. The study uses a candidate gene approach to examine gene–environment interdependence in specific developmental outcomes. Finally, the study includes measures of both brain-based phenotypes and metabolism to explore comorbidities associated with child obesity. One of the unique features of the MAVAN protocol is the extensive measures of the mother–child interaction. The relation between these measures will be discussed.

Results:

Evidence from the MAVAN project shows interesting results about maternal care, families, and child outcomes. In our review, preliminary analyses showing the correlations between measures of maternal care are reported. As predicted, early evidence suggests that maternal care measures are positively correlated, over time.

Conclusions:

This review provides evidence for the feasibility and value of laboratory-based measures embedded within a longitudinal birth cohort study. Though retention of the samples has been a challenge of MAVAN, they are within a comparable range to other studies of this nature. Indeed, the trade-off of somewhat greater participant burden has allowed for a rich database. The results yielded from the MAVAN project will not only describe typical development but also possible targets for intervention. Understanding certain endophenotypes will shed light on the pathogenesis of various mental and physical disorders, as well as their interrelation.  相似文献   
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Cholinergic inputs to the auditory cortex can modulate sensory processing and regulate stimulus‐specific plasticity according to the behavioural state of the subject. In order to understand how acetylcholine achieves this, it is essential to elucidate the circuitry by which cholinergic inputs influence the cortex. In this study, we described the distribution of cholinergic neurons in the basal forebrain and their inputs to the auditory cortex of the ferret, a species used increasingly in studies of auditory learning and plasticity. Cholinergic neurons in the basal forebrain, visualized by choline acetyltransferase and p75 neurotrophin receptor immunocytochemistry, were distributed through the medial septum, diagonal band of Broca, and nucleus basalis magnocellularis. Epipial tracer deposits and injections of the immunotoxin ME20.4‐SAP (monoclonal antibody specific for the p75 neurotrophin receptor conjugated to saporin) in the auditory cortex showed that cholinergic inputs originate almost exclusively in the ipsilateral nucleus basalis. Moreover, tracer injections in the nucleus basalis revealed a pattern of labelled fibres and terminal fields that resembled acetylcholinesterase fibre staining in the auditory cortex, with the heaviest labelling in layers II/III and in the infragranular layers. Labelled fibres with small en‐passant varicosities and simple terminal swellings were observed throughout all auditory cortical regions. The widespread distribution of cholinergic inputs from the nucleus basalis to both primary and higher level areas of the auditory cortex suggests that acetylcholine is likely to be involved in modulating many aspects of auditory processing.  相似文献   
38.
Since the first studies reporting the TP53 p.R337H mutation as founder mutation in Southern and Southeastern Brazil, there has been controversy on its origin. Preliminary analysis of a small subset of Brazilian mutation carriers revealed that the haplotype incided on a Caucasian background. The vast majority of carriers identified today reside in Brazil or, if identified in other countries, are Brazilian immigrants. To our knowledge, the only two exceptions of carriers without a recognizable link with Brazil are two European families, from Portugal and Germany. Haplotype analysis in the Portuguese family revealed the same haplotype identified in Brazilian individuals, but in the German family, a distinct haplotype was found. Knowing that a significant proportion of women with breast cancer (BC) in Southern Brazil are p.R337H carriers, we analyzed p.R337H in a Portuguese cohort of women diagnosed with this disease. Median age at diagnosis among the first 573 patients tested was 60 years and 100 (17.4%) patients had been diagnosed at or under the age of 45 years. Mutation screening failed to identify the mutation in the 573 patients tested. These results are in contrast with the mutation frequency observed in a study including 815 BC‐affected women from Brazil, in which carrier frequencies of 12.1 and 5.1% in pre‐ and postmenopausal women were observed, respectively. These findings suggest that the Brazilian founder mutation p.R337H, the most frequent germline TP53 mutation reported to date, is not a common germline alteration in Portuguese women diagnosed with BC.  相似文献   
39.

Objectives

Understanding the factors contributing to improved postoperative patient outcomes remains paramount. For complex abdominal operations such as pancreaticoduodenectomy (PD), the influence of provider and hospital volume on surgical outcomes has been described. The impact of resident experience is less well understood.

Methods

We reviewed perioperative outcomes after PD at a single high-volume center between 2006 and 2012. Resident participation and outcomes were collected in a prospectively maintained database. Resident experience was defined as postgraduate year (PGY) and number of PDs performed.

Results

Forty-three residents and four attending surgeons completed 686 PDs. The overall complication rate was 44 %; PD-specific complications (defined as pancreatic fistula, delayed gastric emptying, intraabdominal abscess, wound infection, and bile leak) occurred in 28 % of patients. The overall complication rates were similar when comparing PGY 4 to PGY 5 residents (55.3 vs. 43.0 %; p?>?0.05). On univariate analysis, there was a difference in PD-specific complications seen between a PGY 4 as compared to a PGY 5 resident (44 vs. 27 %, respectively; p?=?0.016). However, this was not statistically significant when adjusted for attending surgeon. Logistic regression demonstrated that as residents perform more cases, PD-specific complications decrease (OR?=?0.97; p?<?0.01). For a resident's first PD case, the predicted probability of a PD-specific complication is 27 %; this rate decreases to 19 % by resident case number 15.

Conclusions

Complex cases, such as PD, provide unparalleled learning opportunities and remain an important component of surgical training. We highlight the impact of resident involvement in complex abdominal operations, demonstrating for the first time that as residents build experience with PD, patient outcomes improve. This is consistent with volume–outcome relationships for attending physicians and high-volume hospitals. Maximizing resident repetitive exposure to complex procedures benefits both the patient and the trainee.  相似文献   
40.

Background

Computerized provider order entry (CPOE) has been considered essential for the reduction of medical errors and increased patient safety. Assessment of staff perception regarding a CPOE system is important for satisfaction and adoption. Incorporation of user feedback can greatly improve the functionality of a system and promote user satisfaction.

Questions/Purposes

This study aims to develop an informatics staff satisfaction survey instrument and to understand what components of computerized prescriber order entry (CPOE) contribute to staff satisfaction and its variability over time.

Methods

The 22-question survey was developed by a multidisciplinary group and focused on patient data including demographics, orders, medications, laboratory, and radiology data. The questions were designed to understand if clinicians (1) could easily access the information needed to properly take care of patients, (2) could act upon the information once acquired, (3) could obtain the information clearly, and (4) were alerted to potential errors. The survey was distributed just prior to “go-live,” 6 and 12 months after go-live. Responses were given on a five-point Likert scale.

Results

The survey results post-implementation showed user satisfaction with CPOE. Satisfaction regarding the ease of obtaining orders, medication, and lab data had a significant improvement at 6 and 12 months post-implementation, p < 0.001. Satisfaction that the computerized order entry system provided information needed to take care of their patients improved, p < 0.01. At 1 year post-implementation, user satisfaction declined from 6 months earlier but still demonstrated an overall increase in satisfaction from pre-implementation.

Conclusion

Compared prior to go-live, clinicians are satisfied or very satisfied across multiple spheres and multiple disciplines. At all time points, clinicians were able to obtain information required to take care of their patients. However, post-go-live, it was easier to obtain and act upon as well as more clear and understandable.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-013-9377-1) contains supplementary material, which is available to authorized users.  相似文献   
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