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41.
42.

Purpose

The objective of this study was to determine the impact of a low-fidelity simulation model on mastering the sterile technique during placement of epidural catheters.

Methods

Trainees, including residents and fellows, were given conventional teaching consisting of a lecture and a video demonstration on the appropriate sterile technique to apply during the placement of epidural catheters. The trainees were then provided with a one-on-one demonstration session using a low-fidelity Styrofoam? epidural model, followed by a series of simulation sessions. After conventional teaching and following each simulation session, the trainees were assessed on their performance until competence was achieved based on a 15-point checklist. The retention of competence was subsequently evaluated bi-weekly in clinical practice for four assessments.

Results

Twenty-one trainees participated in the study. The average score for the residents following conventional teaching was 6.0 out of 15 points on the checklist. Following the initial one-on-one hands-on demonstration, the average score increased to 10.8 (difference = 4.8, 95% confidence interval (CI): 3.3 to 6.2; P < 0.001). The average score for the fellows following conventional teaching was 7.9 out of 15 points on the checklist. Following the initial one-on-one hands-on demonstration the average score increased to 11.2 (difference = 3.3, 95% CI: 0.05 to 6.6; P = 0.047). During the retention of competence phase, scores ranged from 13-15 for both residents and fellows.

Conclusion

This study describes a comprehensive teaching model for mastering the sterile technique during epidural catheter placement. It suggests that low-fidelity simulation improves the learning process when used in addition to conventional teaching.  相似文献   
43.
Maternal vitamin D deficiency has been associated with reduced offspring bone mineral accrual. Retinoid‐X receptor‐alpha (RXRA) is an essential cofactor in the action of 1,25‐dihydroxyvitamin D (1,25[OH]2‐vitamin D), and RXRA methylation in umbilical cord DNA has been associated with later offspring adiposity. We tested the hypothesis that RXRA methylation in umbilical cord DNA collected at birth is associated with offspring skeletal development, assessed by dual‐energy X‐ray absorptiometry, in a population‐based mother‐offspring cohort (Southampton Women's Survey). Relationships between maternal plasma 25‐hydroxyvitamin D (25[OH]‐vitamin D) concentrations and cord RXRA methylation were also investigated. In 230 children aged 4 years, a higher percent methylation at four of six RXRA CpG sites measured was correlated with lower offspring bone mineral content (BMC) corrected for body size (β = ?2.1 to ?3.4 g/SD, p = 0.002 to 0.047). In a second independent cohort (n = 64), similar negative associations at two of these CpG sites, but positive associations at the two remaining sites, were observed; however, none of the relationships in this replication cohort achieved statistical significance. The maternal free 25(OH)‐vitamin D index was negatively associated with methylation at one of these RXRA CpG sites (β = ?3.3 SD/unit, p = 0.03). Thus, perinatal epigenetic marking at the RXRA promoter region in umbilical cord was inversely associated with offspring size–corrected BMC in childhood. The potential mechanistic and functional significance of this finding remains a subject for further investigation. © 2014 American Society for Bone and Mineral Research.  相似文献   
44.
Increased activity of muscle metaboreceptors (afferents sensitive to muscle contraction that are responsible for the ventilatory responses to exercise) has been proposed in patients with chronic heart failure (CHF) to constitute a missing link between muscle metabolic abnormalities and exercise overventilation. We looked at this reflex overactivation to determine if it is systemic or limited to a single muscle region in the same human subject. This was done by comparing the metaboreflex response of ventilatory control in the lower and upper limbs in CHF patients and healthy controls. Groups of 15 stable CHF patients (63.7+/-2.7 years) and eight control subjects (69.8+/-1.8 years) performed both leg and arm metaboreflex tests. These metaboreflex tests involved two 5 min episodes of bicycle or handgrip exercise: on one occasion after the exercise the subjects recovered normally, while on the other occasion tourniquet cuffs were inflated around the exercising limb to supra-systolic pressure at the onset of recovery to obtain a regional circulatory occlusion, which isolates and maintains the stimulation of the metaboreflex after exercise. The contribution of the metaboreflex to exercise ventilation was computed as the absolute increment of peak ventilation that was maintained by regional circulatory occlusion. The metaboreceptor contribution to the ventilatory response to both leg exercise (patients, 5.3+/-1.6 litres/min; controls, 0.2+/-0.7 litres/min) and arm exercise (patients, 3.7+/-1.0 litres/min; controls, 0.02+/-0.4 litres/min) was significantly higher in CHF patients (P<0.05). A significant correlation was present between metaboreflex responses to arm and leg exercises (r=0.4, P<0.05). Metaboreflex responses during both types of exercise were inversely correlated with peak oxygen uptake (leg, r=-0.43, P<0.05; arm, r=-0.633, P=0.0009), but only the reflex during arm exercise was correlated with the .V(E) (ventilation)/.V(CO)(2) (CO(2) production) slope (r=0.576, P<0.005). Thus the metaboreflex system is systemically overactive and may potentially contribute to exercise intolerance during both lower- and upper-limb efforts in CHF. This suggests a unique mechanism responsible for overactivation of this system in the skeletal muscle of heart failure patients.  相似文献   
45.
46.
To ensure an efficient and effective response to disaster situations, communities must be prepared at all levels. A disaster presents problems that go beyond the scope of major incident preparedness and requires a response that utilizes all of the available resources that a community may posses, as well as assistance from outside the affected community. In order that the optimum response to a disaster situation is forthcoming, planning must take place that ensures the appropriate response across the service spectrum, including voluntary organizations. The lessons that can be learned from non-governmental organizations in developing world contexts must also be acknowledged and incorporated into the planning process.  相似文献   
47.
BACKGROUND: Elevated oxidized low-density lipoprotein (oxLDL) is associated with atherosclerosis and high cardiovascular risk. Previously, we identified 18 genes in coronary plaque macrophages of hypercholesterolemic pigs that correlated with plaque oxLDL. OBJECTIVE: To determine which of these genes were differentially expressed in blood monocytes and correlated with blood and plaque oxLDL and with plaque complexity. METHODS: RNA expression in monocytes of 27 hypercholesterolemic and 12 control pigs was analyzed with quantitative real-time polymerase chain reaction. RESULTS: Five of 12 genes with detectable expression in monocytes were overexpressed (at P < 0.01 level) in blood monocytes of hypercholesterolemic pigs: ABCA1, SCD, IRF1, SDC2, and TLR2. ABCA1 RNA expression in blood monocytes correlated with blood oxLDL, and its RNA and protein expression was increased prior to atherosclerotic plaque formation. Higher expression of ABCA1 in monocytes was associated with higher plaque complexity and higher plaque oxLDL. Immunostaining of coronary plaques showed the association of ABCA1 with macrophages, lipids, and oxLDL; ABCA1 protein correlated with plaque oxLDL (R(2) = 0.66; P < 0.0001). In THP-1 monocytes, oxLDL induced ABCA1 expression. OxLDL-induced foam cell generation in THP-1 and human monocyte-derived macrophages was associated with a further increase of ABCA1 expression. CONCLUSIONS: The increase of ABCA1 in monocytes in association with blood oxLDL prior to atherosclerotic lesion formation and the association of higher ABCA1 with higher plaque complexity suggests that ABCA1 is an early biomarker of atherosclerosis. Studies in humans are warranted.  相似文献   
48.
49.

Purpose

The purpose of this study was to determine practice patterns of Canadian surgeons managing congenital pulmonary airway malformations (CPAMs) and factors influencing practice.

Methods

Pediatric surgeons in Canada were surveyed regarding their experience, evaluation, and management CPAMs, and what factors they feel qualify patients for observation vs resection. Data were summarized, and Fisher's-Exact and Kruskal-Wallis Tests applied where appropriate.

Results

Sixty eight percent (n = 46) of surgeons responded. However, three surveys were incomplete and excluded. The median age of initial assessment by a pediatric surgeon was one month. 98% (42/43) use CXR for initial imaging, and 83% (36/43) recommend CT scan for further evaluation. Observation is offered always, almost always, or sometimes by 2%, 35% and 37%, respectively. Only 16% almost never, and 9% never offer it. Years in practice was not associated with this decision (p = 0.41). Of surgeons who offer observation, 78% (28/37) use morphology to guide their decision, and 63% (21/37) use lesion size (< 1 cm to < 5cms). 68%(23/37) consider the number of lesions, and 61%(14/23) of those only offer observation to solitary lesions.

Conclusion

Most pediatric surgeons in Canada offer observational management to patients with asymptomatic CPAMs. While practice variations exist, detailed imaging with a CT scan early in life to determine the morphology, size, and number of lesions guides practice.

Level of Evidence

V  相似文献   
50.
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