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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.  相似文献   
3.

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.  相似文献   
4.
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。  相似文献   
5.
《Cirugía espa?ola》2022,100(4):230-234
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.  相似文献   
6.
背景与目的:调强放疗(intensity-modulated radiation therapy,IMRT)中剂量投照失误可导致严重后果,而目前常用的治疗前计划验证方法并不能反映患者真实投照剂量。实现一种评估患者在体剂量执行准确度的方法,能够在分次治疗中及时发现较大剂量错误,避免发生患者投照剂量过高或不足。方法:复旦大学附属肿瘤医院收治的患者首次实施治疗前行锥形束计算机断层成像(cone beam computed tomography,CBCT)扫描,与定位CT图像进行配准保证治疗体位与模拟定位时一致,实时治疗中使用电子射野影像装置(electronic portal imaging device,EPID)获取患者出射剂量影像,并把首次出射EPID影像作为剩余分次治疗的基准值,后续分次实时治疗野结束后快速将其出射EPID影像与对应基准影像进行γ分析比较,以验证治疗计划是否准确执行于患者身上。设计模体实验对治疗部位错误和摆位误差情况进行分析,来评估本方法识别放疗差错的准确性。结果:本方法可有效地识别出IMRT放疗中患者治疗部位错误和非平行于射野角度方向的摆位误差,但对平行于射野角度方向的摆位误差并不敏感,30例鼻咽癌患者临床应用结果中能够直观显示分次治疗间摆位重复性情况。结论:基于EPID实现的一种在体剂量验证方法能够对调强放疗中患者实时剂量的准确性进行评估,在单个治疗野结束后可快速检测出较大治疗错误。  相似文献   
7.

Objective

To determine the association between provider training level and postplacental intrauterine device (IUD) outcomes following insertion instruction by email only.

Study design

We conducted a single-center chart review of demographics, insertion and clinical outcomes within 6 months of delivery for 116 patients who underwent postplacental levonorgestrel 52?mg IUD placement from October 1, 2016, to March 31, 2017.

Results

We confirmed IUD retention, removal or expulsion in 87 of 116 (75.0%) patients by 6 months after delivery. Complete expulsion or removal for malposition occurred in 20 (23.0%) patients and more frequently after vaginal than cesarean delivery (30.2% vs. 4.2%, OR 9.93 [95% CI 1.25–78.96]) and when a postgraduate year (PGY) 1 physician placed the IUD compared to a PGY 2–4 or attending physician (37.5% vs. 14.5%, OR 3.52 [95% CI 1.25–9.94]).

Conclusion

Postplacental levonorgestrel 52?mg IUD expulsion rates are associated with provider training level as well as delivery route, though the individual association of each of these factors is difficult to ascertain given the high degree of collinearity between these two variables in our study.  相似文献   
8.

Objectives

We explored levonorgestrel (LNG) concentrations, bleeding patterns and endometrial thickness in women with epilepsy (WWE) initiating an LNG-intrauterine device (IUD) co-administered with antiepileptic drugs (AEDs).

Study design

This pilot study included 20 WWE ages 18 to 45 years with well-controlled seizures and stable AED regimens initiating a 52-mg LNG-IUD (20 mcg/d initial release). We collected blood and measured endometrial thickness before IUD placement and 21 days, 3 months and 6 months thereafter. Participants recorded bleeding/spotting daily. We measured total LNG (radioimmunoassay), serum hormone binding globulin (SHBG, immunoassay) and calculated the free LNG index. We compared total LNG, free LNG index, SHBG and endometrial thickness over time using a linear mixed-effects model.

Results

Total LNG, free LNG index and SBHG levels remained stable from day 21 throughout. Endometrial thickness decreased from a median of 5.9 mm [interquartile range (IQR) 4.6–7.5] at day 21 to 3.3mm (2.8–4.9) by month 6 (p=0.02). Bleeding and spotting days decreased from a median of 16 (IQR 13–23) in month 1 to 6.5 (IQR 4–8.5) in month 6 regardless of AED regimen.

Conclusion

Like women without epilepsy, WWE initiating the LNG-IUD experience stable total LNG concentrations and decreasing endometrial thickness and bleeding over the first 6 months of use.

Implications

Like women without epilepsy, WWE using antiepileptic drugs can expect a stable LNG concentration and decreasing bleeding during the first 6 months of LNG-IUD use. Our data can be useful for guidance of WWE considering use the LNG-IUD.  相似文献   
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