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51.
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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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Objectives: The steeling effect suggests that early-life adversity can have a beneficial impact later in life. However, little is known about its underlying mechanisms and long-term outcomes . The study aimed to examine the role of early-life adversity (ELA) on successful aging, and whether this relationship can be explained by mental and physical health.

Method: Socio-demographics, early-life adversity (ELA), individual quality of life (iQoL), and mental and physical health of 270 individuals (Mage = 66.82 years, 71.5% female) were assessed. Polynomial regressions and mediation analyses were conducted.

Results: Significant inverse U-shaped associations were found between ELA and iQoL (β = ?.59, p = .005) and between ELA and mental health (β = ?.64, p = .002), but not between ELA and physical health. Furthermore, mental health significantly mediated the relationship between ELA and iQoL (b = ?.84, BCa CI [?1.66, ?.27]).

Conclusion: Highest level of individual quality of life (i.e. successful aging) was related to a moderate amount of ELA. Additionally, mental health significantly mediated this relationship. These findings suggest that some amount of ELA could be beneficial for successful aging. Resource-focused interventions are needed to improve health and promote successful aging for an underdetected, at-risk subgroup with low early-life adversity.  相似文献   

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Background

A vertical incision is recommended for cricothyroidotomy when the anatomy is impalpable, but no evidence-based guideline exists regarding optimum site or length. The Difficult Airway Society guidelines, which are based on expert opinion, recommend an 80–100 mm vertical caudad to cephalad incision in the extended neck position. However, the guidelines do not advise the incision commencement point. We sought to determine the minimum incision length and commencement point above the suprasternal notch required to ensure that the cricothyroid membrane would be accessible within its margins.

Methods

We measured using ultrasound, in 80 subjects (40 males and 40 females) without airway pathology, the distance between the suprasternal notch and the cricothyroid membrane, in the neutral and extended neck positions. We assessed the inclusion of the cricothyroid membrane within theoretical incisions of 0–100 mm in length made at 10 mm intervals above the suprasternal notch.

Results

In the 80 subjects, the distance ranged from 27 to 105 mm. Movement of the cricothyroid membrane on transition from the neutral to extended neck position varied from 15 mm caudad to 27 mm cephalad. The minimum incision required in the extended position was 70 mm in males and 80 mm in females, commencing 30 mm above the suprasternal notch.

Conclusions

An 80 mm incision commencing 30 mm above the suprasternal notch would include all cricothyroid membrane locations in the extended position in patients without airway pathology, which is in keeping with the Difficult Airway Society guidelines recommended incision length.  相似文献   
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