The American Association for Thoracic Surgery (AATS) 2022 Expert Consensus Document: The use of mechanical circulatory support in lung transplantation

ObjectiveThe use of mechanical circulatory support (MCS) in lung transplantation has been steadily increasing over the prior decade, with evolving strategies for incorporating support in the preoperative, intraoperative, and postoperative settings. There is significant practice variability in the use of these techniques, however, and relatively limited data to help establish institutional protocols. The objective of the AATS Clinical Practice Standards Committee (CPSC) expert panel was to review the existing literature and establish recommendations about the use of MCS before, during, and after lung transplantation.MethodsThe AATS CPSC assembled an expert panel of 16 lung transplantation physicians who developed a consensus document of recommendations. The panel was broken into subgroups focused on preoperative, intraoperative, and postoperative support, and each subgroup performed a focused literature review. These subgroups formulated recommendation statements for each subtopic, which were evaluated by the entire group. The statements were then developed via discussion among the panel and refined until consensus was achieved on each statement.ResultsThe expert panel achieved consensus on 36 recommendations for how and when to use MCS in lung transplantation. These recommendations included the use of veno-venous extracorporeal membrane oxygenation (ECMO) as a bridging strategy in the preoperative setting, a preference for central veno-arterial ECMO over traditional cardiopulmonary bypass during the transplantation procedure, and the benefit of supporting selected patients with MCS postoperatively.ConclusionsAchieving optimal results in lung transplantation requires the use of a wide range of strategies. MCS provides an important mechanism for helping these critically ill patients through the peritransplantation period. Despite the complex nature of the decision making process in the treatment of these patients, the expert panel was able to achieve consensus on 36 recommendations. These recommendations should provide guidance for professionals involved in the care of end-stage lung disease patients considered for transplantation.     

Use of the Rocket Technique after Failure of the Direct Aspiration First-Pass Technique in Acute Stroke Thrombectomy

The technical feasibility of the rocket technique was evaluated for patients treated for stroke where the direct aspiration first-pass technique (ADAPT) failed to reach the occlusion site. This single-center retrospective study included data on consecutive patients with a large vessel occlusion of the anterior circulation who underwent mechanical thrombectomy. Of 138 patients, 100 met the inclusion criteria. In 84 patients, a large 0.072-inch inner lumen aspiration catheter was able to reach the occlusion site when deployed with a coaxial microcatheter. In 16 patients, this technique failed, and the microcatheter was replaced with a compliant balloon inflated at the extremity of the aspiration catheter (rocket technique). In 15 of these 16 patients, the rocket technique brought the catheter into contact with the thrombus. In conclusion, when deployment of the ADAPT with a coaxial microcatheter fails to reach the clot site, the rocket technique can safely advance the aspiration catheter to the clot.     

Mechanical Hemolysis Complicating Transcatheter Interventions for Valvular Heart Disease: JACC State-of-the-Art Review

Mechanical intravascular hemolysis is frequently observed following procedures on heart valves and uncommonly observed in native valvular disease. In most cases, its severity is mild. Nevertheless, it can be clinically significant and even life threatening, requiring multiple blood transfusions and renal replacement therapy. This paper reviews the current knowledge on mechanical intravascular hemolysis in valvular disease, before and after correction, focusing on pathophysiology, approach to diagnosis, and impact of other hematological conditions on the resultant anemia. The importance of a multidisciplinary management is underscored. Laboratory data are provided about subclinical hemolysis that is commonly observed following the implantation of surgical and transcatheter valve prostheses and devices. Finally, clinical scenarios are reviewed and current medical and surgical treatments are discussed, including alternative options for inoperable patients.     

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.     

Chinese herbal injections combined with rt-PA intravenous thrombolysis for acute ischemic stroke: A systematic review and meta-analysis protocol

Background:Acute ischemic stroke (AIS) is an important factor leading to adult death and disability globally. For AIS patients who meet certain conditions, recombinant tissue plasminogen activator (rt-PA) intravenous thrombolysis is an important method recommended by national guidelines to achieve vascular recanalization. However, complications such as hemorrhagic transformation and vascular reocclusion after thrombolysis are still unsolved problems in clinical. Several systematic reviews of clinical randomized controlled trials (RCTs) in the past have shown that Chinese herbal injections (CHIs) can improve the neurological function of patients, increase the tolerance of ischemic tissues to hypoxia, and inhibit platelet aggregation. Therefore, this study conducted a meta-analysis of AIS treatment with intravenous thrombolysis alone and compared it with the combined application of CHIs. To evaluate whether CHIs have a synergistic effect on thrombolytic therapy and provide a basis for clinical application.Methods:The following databases will be searched until September 2020: ①English databases: PubMed, Cochrane Library, Embase; ②Chinese databases: CNKI, Wanfang database, Weipu database, SinoMed. RCTs will be included to compare the efficacy of thrombolysis combined with CHIs and thrombolysis alone in the treatment of AIS. Data extraction and risk of bias assessments will be carried out by 2 verifiers independently. The risk of bias will be evaluated through the Cochrane risk of bias tool. Review Manager software 5.3 will be used for statistical analysis.Results:This study will provide comprehensive evidence for the treatment of AIS by CHIs combined with intravenous thrombolysis from multiple aspects.Conclusion:The conclusion of the meta-analysis will provide a basis for judging whether CHIs combined with intravenous thrombolysis is an effective measure for the treatment of AIS.Ethics and dissemination:Ethical approval is not needed because this study will be based on data that already published. We will publish the findings of this study in a peer-reviewed journal and related conferences.PROSPERO registration number:CRD42020215546.     

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.     

超声及应变式弹性成像预测超声引导下腘静脉置入血管鞘用于治疗下肢深静脉血栓形成成功与否

目的 分析超声及应变式弹性成像预测超声引导下置入腘静脉血管鞘治疗下肢深静脉血栓形成(DVT)成功与否的价值。方法 回顾性分析103例接受超声引导下置入患侧腘静脉血管鞘的DVT患者的术前超声资料,比较置入血管鞘失败与成功病例腘静脉超声及应变式弹性成像表现差异;绘制差异有统计学意义超声参数的受试者工作特征曲线,获得其预测血管鞘置入失败的阈值,对每个参数阈值赋值1分,得到联合超声评分,以实际置入结果为标准,评价超声单一参数及联合评分的预测效能。结果 103例中,对100例行单侧、3例行双侧腘静脉置入血管鞘,包括左侧腘静脉71支、右侧35支,共106支腘静脉;对其中95支腘静脉置入血管鞘成功(成功组),11支失败(失败组)。相比成功组,失败组腘静脉内径及腘静脉与腘动脉内径比值均较小,血栓为等或高回声,与血管壁边界模糊,腘静脉应变式弹性评分为硬。以超声单一参数及联合评分预测置入血管鞘成功与否的曲线下面积分别为0.909、0.926、0.865、0.899、0.958及0.940(P均＜0.001)。结论 患侧腘静脉超声及应变式弹性成像能有效预测对下肢DVT患者行超声引导下置入腘静脉血管鞘成功与否。     

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.