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991.
992.
BackgroundA small number of patients are disproportionally readmitted to hospitals. The Complex High Admission Management Program (CHAMP) was established as a multidisciplinary program to improve continuity of care and reduce readmissions for frequently hospitalized patients.ObjectiveTo compare hospital utilization metrics among patients enrolled in CHAMP and usual care.DesignPragmatic randomized controlled trial.ParticipantsInclusion criteria were as follows: 3 or more, 30-day inpatient readmissions in the previous year; or 2 inpatient readmissions plus either a referral or 3 observation admissions in previous 6 months.InterventionsPatients randomized to CHAMP were managed by an interdisciplinary team including social work, physicians, and pharmacists. The CHAMP team used comprehensive care planning and inpatient, outpatient, and community visits to address both medical and social needs. Control patients were randomized to usual care and contacted 18 months after initial identification if still eligible.Main MeasuresPrimary outcome was number of 30-day inpatient readmissions 180 days following enrollment. Secondary outcomes were number of hospital admissions, total hospital days, emergency department visits, and outpatient clinic visits 180 days after enrollment.Key ResultsThere were 75 patients enrolled in CHAMP, 76 in control. Groups were similar in demographic characteristics and baseline readmissions. At 180 days following enrollment, CHAMP patients had more inpatient 30-day readmissions [CHAMP incidence rate 1.3 (95% CI 0.9–1.8) vs. control 0.8 (95% CI 0.5–1.1), p=0.04], though both groups had fewer readmissions compared to 180 days prior to enrollment. We found no differences in secondary outcomes.ConclusionsFrequently hospitalized patients experienced reductions in utilization over time. Though most outcomes showed no difference, CHAMP was associated with higher readmissions compared to a control group, possibly due to consolidation of care at a single hospital. Future research should seek to identify subsets of patients with persistently high utilization for whom tailored interventions may be beneficial.Trial RegistrationClinicalTrials.gov identifier: NCT03097640; https://clinicaltrials.gov/ct2/show/NCT03097640KEY WORDS: care transitions, readmissions, care models, continuity of care, randomized controlled trial

A small number of patients account for a disproportionate number of hospital readmissions.1 While medically diverse, many patients who are frequently hospitalized have behavioral or social needs that require holistic care models emphasizing more than medical care alone.2 This population challenges a system of care that fragments hospital-based care and ambulatory care, creating systematic discontinuity for patients who may require longitudinal relationship-based care to meet their complex needs.3 In qualitative studies, patients who are frequently hospitalized report frustration with care fragmentation, causing them to perceive a lack of continuity and a loss of trust with the medical system.4Innovative care models have sought to reduce readmissions through redesigning care delivery, improving care coordination, and connecting patients to existing resources.58 A systematic review of interventions for frequently hospitalized patients found a heterogeneous group of care models.9 Importantly, the majority of studies were observational. Many patients experience a reduction in utilization after an initial period of frequent admissions,10 limiting the ability of observational studies to measure a specific program’s effect due to the natural decline in readmissions over time. A randomized trial of a “healthcare hotspotting” intervention for patients in Camden, NJ, reported no change in hospitalization rates compared to a control group.11 Though this intervention was an intensive interdisciplinary effort that enrolled patients while still hospitalized, it focused primarily on connecting patients to existing outpatient resources. Other intensive outpatient-only interventions have failed to reduce healthcare utilization.12 Interventions that focus on improving care across clinical settings (i.e., both inside and outside of the hospital) may have a different effect.We created the Complex High Admission Management Program (CHAMP) as a quality improvement initiative to improve inpatient and outpatient care and reduce inpatient readmissions of patients frequently admitted to our hospital. The CHAMP multidisciplinary team works to foster longitudinal relationships with patients who suffer from systematic discontinuity. A pilot pre-post analysis of CHAMP observed reductions in readmission;13 however, results may have been confounded by the aforementioned tendency for utilization to decline over time.10 In this study, we conducted a randomized trial of CHAMP compared with usual care to accurately assess the program’s effect on hospital readmissions.  相似文献   
993.
The pyrethroid tetramethrin greatly prolongs the sodium current during step depolarization and the sodium tail current associated with step repolarization of the squid axon membrane. Non-linear current-voltage relationships for the sodium tail current were analyzed to assess the open sodium channel properties which included the permeation of various cations, calcium block and cation selectivity. Tetramethrin had no effect on any of these properties. It was concluded that tetramethrin modifies the sodium channel gating machinery without affecting the pore properties.  相似文献   
994.
995.
Calibration of the spatial sensitivity functions of coil arrays is a crucial element in parallel magnetic resonance imaging (PMRI). The most common approach has been to measure coil sensitivities directly using one or more low-resolution images acquired before or after accelerated data acquisition. However, since it is difficult to ensure that the patient and coil array will be in exactly the same positions during both calibration scans and accelerated imaging, this approach can introduce sensitivity miscalibration errors into PMRI reconstructions. This work shows that it is possible to extract sensitivity calibration images directly from a fully sampled central region of a variable-density k-space acquisition. These images have all the features of traditional PMRI sensitivity calibrations and therefore may be used for any PMRI reconstruction technique without modification. Because these calibration data are acquired simultaneously with the data to be reconstructed, errors due to sensitivity miscalibration are eliminated. In vivo implementations of self-calibrating parallel imaging using a flexible coil array are demonstrated in abdominal imaging and in real-time cardiac imaging studies.  相似文献   
996.
997.

Objective

Thoracic endovascular aortic repair (TEVAR) has demonstrated encouraging results and is gaining increasing acceptance as a treatment option for aortic aneurysms and dissections. Yet, its role in managing proximal aortic pathologies is unknown—this is important because in proximal (Stanford type A) aortic dissections, 10% to 30% are not accepted for surgery and 30% to 50% are technically amenable for TEVAR. We describe our case series of type A aortic dissections treated by using TEVAR.

Methods

Between year 2009 and 2016, 12 patients with acute, subacute, or chronic type A aortic dissection with the proximal entry tear located between the coronaries and brachiocephalic artery were treated with TEVAR at 3 centers. Various stent-graft configurations were used to seal the proximal entry tear in the ascending aorta under rapid pacing.

Results

A total of 12 patients (9 male, 3 female), mean age 81 ± 7 years, EuroSCORE II 9.1 ± 4.5, underwent TEVAR for the treatment of type A aortic dissection. Procedural success was achieved in 11 of 12 patients (91.7%). There was 1 minor stroke and 1 intraprocedural death. No additional deaths were reported at 30 days. At 36 months, there were 4 further deaths (all from nonaortic causes). The mean survival of these 4 deceased was 23 months (range 15-36 months). Follow-up computed tomography demonstrated favorable aortic remodeling.

Conclusions

TEVAR is feasible and reveals promising early results in selected patients with type A aortic dissection who are poor candidates for surgical repair. The current iteration of stent-graft technology, however, needs to be adapted to features specific to the ascending aorta.  相似文献   
998.
7β-(6-取代-2-喹诺酮-3-乙酰氨基)头孢菌素的合成   总被引:1,自引:0,他引:1  
以6-取代-2-喹诺酮-3-乙酸为侧链,用CDI法和潘化酯法与7-ADCA,7-ACA,7-ACT,和7-ACD缩合,合成了16个新的7β-(6-取代-2-喹诺酮-3-乙酰氨基)头孢菌素类化合物,通过溶媒转提,葡聚糖凝胶(Sephadex LH-20)柱层析及离心薄层层析分离精制,得到纯品。初步体外抑菌试验表明:新化合物对革兰氏阳性及某些阴性菌具有高度敏感性。大多数化合物对所试试验菌的抗菌活性与头孢唑啉和青霉素G钠相当,有些比它们还强。  相似文献   
999.
For solid-phase peptide synthesis, 2, 4-dimethoxy-4′ -hydroxybenzhydrol linker was prepared via lithium borohydride reduction of 2, 4-dimethoxy-4′-hydroxybenzophenone. The potassium salt of the linker was coupled to chloromethylpolystyrene. This method proved to be better than use of the cesium salt. This new synthesis gave a polymer with appropriate structure and a good degree of substitution.  相似文献   
1000.
Crop impaction and candidiasis was encountered in young, meat-type pigeons (hybrid line). Prominent lesions were epithelial hyperplasia, severe hydropic degeneration and microvesicular formation in the crop. There was tissue invasion by candida blastospores and pseudohyphae. The cause was attributed to hand-feeding too much unsuitable feed at too early an age. Similar lesions were induced in an experimental study.  相似文献   
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