Prosthetic choice in mitral valve replacement for severe chronic ischemic mitral regurgitation: Long-term follow-up

BackgroundProsthetic choice for mitral valve replacement is generally driven by patient age and patient and surgeon preference, and current guidelines do not discriminate between different etiologies of mitral valve disease. Our objective was to assess and compare short- and long-term outcomes after mitral valve replacement among patients with biological or mechanical prostheses in the setting of severe ischemic mitral regurgitation.MethodsBetween 2000 and 2016, 424 patients underwent mitral valve replacement for severe ischemic mitral regurgitation at our institution, using biological prosthesis in 188 (44%) and mechanical prosthesis in 236 (56%). A 1:1 propensity score match (n = 126 per group) and inverse probability of treatment weighting were used to compare groups. Short-term outcomes included in-hospital mortality and other cardiovascular adverse events. Long-term outcomes included survival and hospital readmission for cardiovascular causes, stroke, and major bleeding.ResultsIn-hospital mortality and early postoperative adverse events were similar between groups in the propensity score match and inverse probability of treatment weighting cohorts. Overall long-term survival was similar at 5 and 9 years, but mechanical prosthesis recipients were more frequently readmitted to hospital for cardiovascular causes, including stroke and non-neurological bleeding in propensity score matching and inverse probability of treatment weighting analyses (all P values < .004). Type of prosthesis did not independently influence all-cause mortality (hazard ratio, 1.01; 95% confidence interval, 0.71-1.43; P = .959), but placement of a mechanical prosthesis was associated with increased risk of readmission for cardiovascular events (hazard ratio, 1.65; 95% confidence interval, 1.17-2.32; P = .004) among matched patients.ConclusionsThe type of prosthesis has no influence on long-term survival among patients with severe ischemic mitral regurgitation undergoing mitral valve replacement. There may be an increased risk of neurologic events and serious bleeding associated with mechanical prostheses.     

High-flow via a tracheostomy tube and speaking valve during weaning from mechanical ventilation and tracheostomy

Background

Weaning from mechanical ventilation and tracheostomy after prolonged intensive care consume enormous resources with optimal management not currently well described. Restoration of respiratory flow via the upper airway is essential and early cuff-deflation using a one-way valve (OWV) is recommended. However, extended OWV use may cause dry airways and thickened secretions which challenge the weaning process. High-flow therapy via the tracheostomy tube (HFT-T) humidifies inspired air and may be connected via an in-line OWV (HFT-T-OWV) alleviating these problems. We aim to provide clinical and experimental data on the safety of HFT-T-OWV along with a practical guide to facilitate clinical use during weaning from mechanical ventilation and tracheostomy.

Methods

Data on adverse events of HFT-T-OWV were retrieved from a quality register for patients treated at an intensive care rehabilitation center between 2019 and 2022. Benchtop experiments were performed to measure maximum pressures and pressure support generated by HFT-T-OWV at 25–60 L/min flow using two different HFT-T adapters (interfaces). In simulated airway obstruction using a standard OWV (not in-line) maximum pressures were measured with oxygen delivered via the side port at 1–3 L/min.

Results

Of 128 tracheostomized patients who underwent weaning attempts, 124 were treated with HFT-T-OWV. The therapy was well tolerated, and no adverse events related to the practice were detected. The main reason for not using HFT-T-OWV was partial upper airway obstruction using a OWV. Benchtop experiments demonstrated HFT-T-OWV maximum pressures <4 cmH₂O and pressure support 0–0.6 cmH₂O. In contrast, 1–3 L/min supplemental oxygen via a standard OWV caused pressures between 84 and 148 cmH₂O during simulated airway obstruction.

Conclusions

Current study clinical data and benchtop experiments indicate that HFT-T-OWV was well tolerated and appeared safe. Pressure support was low, but humidification may enable extended use of a OWV without dry airway mucosa and thickened secretions. Results suggest the treatment could offer advantages to standard OWV use, with or without supplementary oxygen, as well as to HFT-T without a OWV, for weaning from mechanical ventilation and tracheostomy. However, for definitive treatment recommendations, randomized clinical trials are needed.     

呼吸机自动测量气道阻断压与标准测量方法的一致性

目的 验证呼吸机自动测量的气道阻断压(airway occlusion pressure,P0.1)与标准测量方法的一致性,以及不同触发形式对自动测量结果的影响。方法 选择采用非阻断自动测量P0.1的呼吸机,分别进行模拟肺和临床试验。调节全自动自主呼吸模拟肺,模拟具有不同呼吸努力和呼吸力学特征的48种状态,应用待检测呼吸机,以压力支持通气模式为模拟肺进行通气。临床研究部分纳入15例接受压力支持通气的成年患者。两部分研究均随机交叉应用压力和流量触发,采集呼吸机自动监测的P0.1后,采用标准呼气末气道阻断法进行P0.1测量,作为标准参考值。采用Bland-Altman检验分析P0.1呼吸机监测值与标准参考值的一致性,计算残差(呼吸机监测值-标准参考值)和95%一致性区间,比较不同触发形式对残差的影响。结果 在模拟肺验证中,P0.1呼吸机监测值与标准参考值之间的残差(95%一致性区间)在压力和流量触发下分别为0.04(－0.63~0.70)和－0.54(－1.44~0.36)cmH₂O(1 cmH₂O=0.098 kPa),两者相比差异具有统计学意义(P<0.001)。临床观察获得了相似的结果,压力和流量触发时的残差(95%一致性区间)分别为－0.11(－0.73~0.52)和－0.54(－1.50~0.59)cmH₂O,差异无统计学意义(P>0.05),表明呼吸机监测值与标准参考值间存在一致性。结论 压力触发时,呼吸机非阻断法自动测量的P0.1与标准方法具有良好的一致性。而流量触发明显低估P0.1,建议自动监测时切换到压力触发。     

Esofagogastrostomía triangular mecánica: aspectos técnicos y resultados iniciales

IntroductionEsophageal cancer represents the eighth neoplasm worldwide. The therapeutic approach is interdisciplinary, with surgery being the most effective option. Several techniques have been proposed to perform esophagogastrostomy after esophagectomy, among them mechanical triangular esophagogastrostomy, with a little experience published in the Western literature on the latter. The objective of this study is to describe the technical aspects and initial results of triangular esophagogastrostomy anastomosis.MethodsA retrospective review of the patients who underwent esophagectomy according to the McKeown technique was performed, those in which triangular esophagogastrostomy anastomosis was implemented, between October 2017 and March 2020 in our hospital.ResultsA total of 14 patients were included, with a mean age of 63 years. The mean operative time was 436 minutes (360-581), being diagnosed of anastomotic leak 3 of the 14 patients (21.4%), as well as 3 patients presented anastomotic stenosis. The median stay was 20 days, without any death in the series.ConclusionsMultiple publications suggest the superiority in terms of anastomotic leak and anastomotic stenosis of the mechanical triangular anastomosis, which was also observed in our series, in which despite the small sample, a rapid improvement was observed in the indicators after the first cases. Therefore, this type of anastomosis may be a safe option for performing esophagogastric anastomosis after esophagectomy, being necessary more definitive conclusive studies.     

一期支架置入补救治疗急性后循环大动脉闭塞机械取栓术失败病人的疗效

目的 探讨一期支架置入术作为急性后循环大动脉闭塞机械取栓失败后补救性治疗的疗效。方法 回顾性分析2016年1月至2018年6月单独支架取栓或联合抽吸取栓治疗后循环大动脉闭塞所致急性脑卒中186例，146例实现闭塞血管成功再通；40例血流恢复较差，其中28例接受一期支架置入补救性治疗（支架组）；12例拒绝支架置入治疗（非支架组），仅给予基础抗栓治疗。结果 支架组血管再通率（75.00%）明显高于非支架组（0％；P<0.05）。术后90 d，支架组预后良好率（64.29%，改良Rankin量表评分0~2分）明显高于非支架组（8.33%；P<0.05）。支架组术后90 d病死率（21.43%）明显低于非支架组（83.33%；P<0.05）。支架组症状性颅内出血发生率（7.14%）与非支架组（16.67%）无统计学差异（P>0.05）。结论 一期支架置入术作为急性后循环大动脉闭塞机械取栓术失败的补救性治疗，再通率高，并发症少，可显著改善病人的预后。     

Impact of Treatment Time on the Long-Term Outcome of Stroke Patients Treated With Mechanical Thrombectomy

Objective

To assess the long-term functional outcome of stroke in patients treated with mechanical thrombectomy (MT) performed during work hours (on-hours) versus after-hours, weekends, and official holidays (off-hours).

接受机械取栓治疗的急性脑梗死患者血栓特征研究进展

急性脑梗死是威胁我国人民健康的重大疾病,其致死率及致残率均较高,造成了沉重的社会负担。及时开通导致梗死的责任血管以恢复脑灌注是治疗该病的关键。机械取栓技术的应用使得患者的血栓组织能够被获取并得到研究。本文介绍了近年来通过机械取栓术获取的血栓的相关研究发现,以纤维蛋白为主的血栓是造成取栓困难的重要组织学原因,影像学方法可以在术前评估血栓特征。这些发现提示临床工作者可以积极开发新型血栓取出装置用于处理难治性血栓,并有必要探索精确便捷的血栓特征影像学评价方法,从而提高机械取栓疗效。     

Selective Laser Melting of Al-Based Matrix Composites with Al2O3 Reinforcement: Features and Advantages

Aluminum matrix composites (AMC) are of great interest and importance as high-performance materials with enhanced mechanical properties. Al₂O₃ is a commonly used reinforcement in AMCs fabricated by means of various technological methods, including casting and sintering. Selective laser melting (SLM) is a suitable modern method of the fabrication of net-shape fully dense parts from AMC with alumina. The main results, achievements, and difficulties of SLM applied to AMCs with alumina are discussed in this review and compared with conventional methods. It was shown that the initial powder preparation, namely the particle size distribution, sphericity, and thorough mixing, affected the final microstructure and properties of SLMed materials drastically. The distribution of reinforcing particles tends to consolidate the near-melting pool-edges process because of pushing by the liquid–solid interface during the solidification process that is a common problem of various fabrication methods. The achievement of an homogeneous distribution was shown to be possible through both the thorough mixing of the initial powders and the precise optimization of SLM parameters. The strength of the AMCs fabricated by the SLM method was relatively low compared with materials produced by conventional methods, while for superior relative densities of more than 99%, hardness and tribological properties were obtained, making SLM a promising method for the Al-based matrix composites with Al₂O₃.