Predefined vs data-guided training prescription based on autonomic nervous system variation: A systematic review

Monitoring variations in the functioning of the autonomic nervous system may help personalize training of runners and provide more pronounced physiological adaptations and performance improvements. We systematically reviewed the scientific literature comparing physiological adaptations and/or improvements in performance following training based on responses of the autonomic nervous system (ie, changes in heart rate variability) and predefined training. PubMed, SPORTDiscus, and Web of Science were searched systematically in July 2019. Keywords related to endurance, running, autonomic nervous system, and training. Studies were included if they (a) involved interventions consisting predominantly of running training; (b) lasted at least 3 weeks; (c) reported pre- and post-intervention assessment of running performance and/or physiological parameters; (d) included an experimental group performing training adjusted continuously on the basis of alterations in HRV and a control group; and (e) involved healthy runners. Five studies involving six interventions and 166 participants fulfilled our inclusion criteria. Four HRV-based interventions reduced the amount of moderate- and/or high-intensity training significantly. In five interventions, improvements in performance parameters (3000 m, 5000 m, Loadmax, Tlim) were more pronounced following HRV-based training. Peak oxygen uptake () and submaximal running parameters (eg, LT1, LT2) improved following both HRV-based and predefined training, with no clear difference in the extent of improvement in . Submaximal running parameters tended to improve more following HRV-based training. Research findings to date have been limited and inconsistent. Both HRV-based and predefined training improve running performance and certain submaximal physiological adaptations, with effects of the former training tending to be greater.     

An off-the-shelf plasma-based material to prevent pacemaker pocket infection

Bacterial infection of subcutaneous “pockets” housing cardiovascular implantable electronic devices is a significant clinical complication. In this study, pacemakers encapsulated in a blood plasma-based material (PBM) composited with antibiotics were investigated for use as prophylactics against such infections. PBMs, which are made from pooled allogeneic plasma and platelets, are off-the-shelf biomaterials that can be manufactured in the form of complex 3D shapes, extrudable putties, or injectable pastes. In vitro studies with PBM pastes formulated with rifampicin and minocycline demonstrated antibiotic release over 6 days, activity against Escherichia coli, and reduced cytotoxic effects of the antibiotics on fibroblasts. The materials were also evaluated in vivo in a rabbit model in which pacemaker pockets were inoculated with methicillin-resistant Staphylococcus aureus (S. aureus) strain and examined 1 week later. The pockets containing the pacemaker plus S. aureus were grossly purulent and culture positive, whereas pockets into which PBM with antibiotics were injected around the pacemaker were free of purulence and culture negative (p < 0.001). None of the pockets into which PBM without antibiotics were placed demonstrated purulence, but 60% were culture positive. These results demonstrate the potential of PBMs to deliver antibiotics to diminish the incidence of pocket infections for pacemakers and other implantable devices.     

Utilization and Complications of Central Venous Access Devices in Oncology Patients

Purpose: To describe how central venous access devices (CVADs) are utilized for ambulatory oncology patients and to evaluate the rate of complications. Method: Single institution retrospective study of oncology patients with CVADs who received systemic treatment at the Walker Family Cancer Centre (WFCC) between 1 January and 31 December 2018. Results: A total of 480 CVADS were placed in 305 patients, of which 408 (85%) were peripherally inserted central catheters (PICCs) and 72 (15%) were implanted vascular access devices (PORTs). The incidence of early and late complications was 9% and 24%, respectively. For the entire cohort, the rate of venous thromboembolism (VTE) was 16%, of which 9% were CVAD-related thrombosis (CRTs) and 7% were distant VTE. The CRT rates were similar for PICCs and PORTs (9% vs. 7%). A total of 6% of CVADs were complicated by infection (i.e., localized infections and bacteremia), with a total infection rate of 0.43 and 0.26 per 1000 indwelling days for PICCs and PORTs, respectively. The incidence of central line associated bloodstream infections (CLABSI) was greater for PICCs than PORTs, at a rate of 0.22 compared with 0.08 per 1000 indwelling days, respectively. The premature catheter removal rate was 26% for PICCs and 18% for PORTs. PORTs required more additional hospital visits. Conclusions: PICCs were utilized more frequently than PORTs and had a higher rate of premature removal. The rates of VTE and CRT were similar for both CVAD types. PORTs had a lower rate of infection per 1000 indwelling days. However, the management of PORT related complications required more visits to the hospital and oncology clinic.     

Successful Use of Surgically Placed Impella 5.0 and Central Extracorporeal Membrane Oxygenation Circuit in a Patient with Postcardiotomy Shock

The Impella 5.0, a percutaneously inserted left ventricular assist device, has been used to support patients who have severe heart failure or who are undergoing high-risk percutaneous coronary intervention. We report our surgical placement of the Impella 5.0, through a graft sewn to the aorta, to unload the left ventricle of a 59-year-old man who was undergoing venoarterial extracorporeal membrane oxygenation for postcardiotomy shock. The patient underwent successful placement of a long-term left ventricular assist device before his discharge from the hospital. The versatility of the Impella 5.0 is exemplified in this patient who was successfully bridged to long-term support.     

压力梯度长袜和间歇充气装置预防恶性肿瘤患者术后下肢深静脉血栓形成的效果

目的 观察单纯应用压力梯度长袜（CS）或与间歇充气装置（IPC）联合使用预防恶性肿瘤患者术后下肢深静脉血栓（DVT）形成的效果及可能的机制。方法 胸科、泌尿外科、肝胆外科恶性肿瘤根治手术患者240例，随机分为4组：对照组、单纯CS组、CS＋IPC全程组、CS＋IPC术后组，每组60例。术后3～8d内行双下肢深静脉超声检查，记录DVT例数及血栓发生部位（大腿或小腿）。随机选择对照组和CS＋IPC全程组各15例患者，分别于术前、切皮后2h及术后24h各采集外周静脉血2ml，测定D-二聚体（D-D）、纤溶酶原激活物抗原（tPA-Ag）、纤溶酶原激活物抑制物（PAI）、血管性血友病因子（vWF）、凝血酶原时间（PT）和活化部分凝血活酶时间（APTT）。结果 术后3-8d对照组、CS＋IPC全程组、CS＋IPC术后组和单纯CS组DVT发生率分别为49．3％、15．0％、23．3％和30．0％（P〈0．05）。所有发生DVT患者中，除CS组发现1例近端DVT外，其余均为远端DVT。发生DVT患者年龄、卧床时间、危险因素个数等与未发生血栓患者相比差异有统计学意义（P〈0．05）。凝血，纤溶指标：与对照组比较，切皮后2h，CS＋IPC全程组vWF升高，D-D、tPA-Ag降低（P〈0．05），术后24h对照组和cs＋IPC全程组间D—D、vWF、tPA-Ag及PAI差异无统计学意义。结论 CS＋IPC全程或术后使用均能降低高危患者术后DVT的发生，其中CS＋IPC全程使用预防效果最好，可能与IPC增加纤溶活性有关。