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Background

Pump speed optimization in patients implanted with a ventricular assist device represents a major challenge during the follow-up period. We present our findings on whether combined invasive hemodynamic ramp tests and cardiopulmonary exercise testing (CPX) can help optimize patient management.

Methods

Eighteen patients implanted with a HeartMate 3 (HM3) device underwent ramp tests with right heart catheterization (including central venous pressure [CVP], pulmonary artery pressure, pulmonary capillary wedge pressure [PCWP], and blood pressure) and echocardiography. Data were recorded at up to 4 speed settings. Speed changes were in steps of 200 revolutions/min (rpm). Evaluation of functional capacity by CPX was conducted according to the modified Bruce protocol.

Results

Only 30% of patients had normal PCWPs at their original rpm settings. In going from lowest to highest speeds, cardiac output improved by 0.25 ± 0.35 L/min/step (total change, 1.28 ± 0.3 L/min), and PCWP decreased by 1.9 ± 0.73 mm Hg/step (total change, 6 ± 1.6 mm Hg). CVP and systolic blood pressure did not change significantly with rpm. The rpm assessment was adjusted based on test results to achieve CVPs and PCWPs as close to normal limits as possible, which was feasible in all patients. On CPX, all patients demonstrated good performance (peak VO2, 16.8 ± 3.5 mL/kg/min).

Conclusion

Hemodynamic ramp testing provides an objective means of optimizing rpm, and has the potential to provide good exercise tolerance.  相似文献   
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Unilateral lesions of visual cortex have the secondary consequence of suppressing visual circuits in the midbrain superior colliculus (SC), collectively producing blindness in contralesional space (“hemianopia”). Recent studies have demonstrated that SC visual responses and contralesional vision can be reinstated by a non‐invasive multisensory training procedure in which spatiotemporally concordant visual‐auditory pairs are repeatedly presented within the blind hemifield. Despite this recovery of visual responsiveness, the loss of visual cortex was expected to result in permanent deficits in that hemifield, especially when visual events in both hemifields compete for attention and access to the brain's visuomotor circuitry. This was evaluated in the present study in a visual choice paradigm in which the two visual hemifields of recovered cats were simultaneously stimulated with equally valent visual targets. Surprisingly, the expected disparity was not found, and some animals even preferred stimuli presented in the previously blind hemifield. This preference persisted across multiple stimulus intensity levels and there was no indication that animals were less aware of cues in the previously blind hemifield than in its spared counterpart. Furthermore, when auditory cues were combined with visual cues, the enhanced performance they produced on a visual task was no greater in the normal than in the previously blind hemifield. These observations suggest that the multisensory rehabilitation paradigm revealed greater inherent visual information processing potential in the previously blind hemifield than was believed possible given the loss of visual cortex.  相似文献   
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目的:探讨中西医结合护理干预妊娠晚期合并急性单纯性阑尾炎的临床疗效。方法:将2017 年9 月—2018 年12月于我院接受中西医结合保守治疗的31 例妊娠晚期合并急性单纯性阑尾炎患者作为研究对象,按随机数表法随机分为中西医结合护理组(观察组16 例)与常规护理组(对照组15 例),对照组采取常规护理措施,观察组在对照组的基础上增加中西医结合护理措施,对比两组患者的临床疗效。结果:观察组患者的心理状态变化、新生儿体质状况以及临床疗效等指标等情况均明显优于对照组,且组间对比差异显著有统计学意义(P < 0.05)。结论:中西医结合护理对妊娠晚期合并急性单纯性阑尾炎有较好的临床效果,可减少、甚至避免孕妇因合并急性阑尾炎而造成的打击和创伤。  相似文献   
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Abstract

In recent years, a proliferation of mentoring projects have been established in England and Wales, targeted at both offenders and drug users. This is, in part, a consequence of high-level encouragement to establish such schemes. Mentoring features throughout the Ministry of Justice’s Transforming Rehabilitation strategy as a tool to support offenders to ‘get their lives back on track’, and the 2017 drug strategy highlights the importance of peer mentoring for those engaged in treatment services. Using Kingdon’s multiple streams approach, the article accounts for the popularity of mentoring within criminal justice and drug policy despite a less than convincing evidence-base. His model is based upon an appreciation of three streams (problem, policies and politics) which coincide when a compelling problem is linked to a plausible solution that meets the test of political feasibility. It is argued that mentoring has come to be viewed as a cost-effective solution to reduce reoffending and improve drug treatment outcomes despite a lack of conclusive evidence. It has garnered support because of its fit with dominant political discourses around citizenship and civil society. Mentoring has received support from within and without government but its inherent appeal overshadows a lack of clarity of what mentoring is and insufficient theoretical understanding of why it might be effective. Consequently, it is proposed that the Good Lives Model, a strengths-based rehabilitation theory, might provide an appropriate theoretical base and inform discussions about the role of mentoring within desistance and recovery journeys.  相似文献   
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