可回收式下腔静脉滤器预防肺栓塞临床效果分析

目的评价可回收式下腔静脉滤器(IVCF)在预防下肢深静脉血栓(DVT)导致肺栓塞中的的临床作用。方法46例下肢深静脉血栓形成患者为预防肺栓塞置入可回收式下腔静脉滤器,随访观察无滤器并发症发生及肺栓塞的出现。结果35例在放置12～14天取出,11例患者因滤器周围血栓形成,下腔静脉置管溶栓5～7天,5例血栓消失,滤器成功回收,另6例溶栓效果不佳,长期留置滤器。在取出的40例中,12例肉眼可见絮状血栓。结论下腔静脉滤器置入术能安全、有效预防肺栓塞,是治疗下肢深静脉血栓的重要方法之一。     

铅门跟随与固定技术结合有无均整器模式的鼻咽癌IMRT剂量学比较

目的:研究铅门跟随与固定技术结合有无均整器4种模式在鼻咽癌调强放疗中的剂量分布,为选择最优治疗技术提供指导和参考。方法:选择10例早期鼻咽癌患者,采用Varian公司的Eclipse 13.6治疗计划系统,设计铅门跟随无均整器模式（JTT-FFF）、铅门跟随有均整器模式（JTT-FF）、铅门固定无均整器模式（SJT-FFF）和铅门固定有均整器模式（SJT-FF）4种治疗计划,评估靶区、危及器官和正常组织剂量学参数以及机器跳数。结果:4组计划的靶区剂量分布均达到临床要求,且靶区的适形度差异无统计学意义（P>0.05）;SJT-FF计划靶区的均匀性最好,相对于JTT计划差异有统计学意义（P<0.05）,但相对于SJT-FFF计划差异无统计学意义（P>0.05）。在JTT-FFF计划中,晶体的最大剂量以及眼球、口腔、颞叶、下颌骨和Body的平均剂量最低但机器跳数最多;在JTT-FF计划中,脑干、垂体、交叉、视神经、脊髓的最大剂量和腮腺、喉、内耳的平均剂量最低。结论:4种计划均能满足临床使用要求,靶区适形度差异无统计学意义,JTT计划靶区均匀性相对于SJT计划要差,但能更好地降低危及器官和正常组织的受照剂量。     

呼吸过滤器对老年患者全身麻醉术后呼吸道感染的预防作用

目的 观察呼吸过滤器（BF）对老年患者全身麻醉插管术后并发呼吸道感染的预防作用.方法 选择全身麻醉插管择期行胃肠肿瘤根治术的老年患者100例,随机分成两组各50例.观察组使用BF,对照组不使用BF.分别对麻醉前后两组气管导管末端、呼吸回路气管端采样进行细菌培养;统计两组术后7d内下呼吸道感染的发生率.结果 术后两组气管导管末端均检测到大量细菌生长.对照组呼吸回路气管端检测到大量细菌生长[（305.2±12.4） CFU/cm2],而观察组[（10.2±2.0）CFU/cm2]几乎无细菌生长,两组比较差异有统计学意义（t=166.077,P＜0.01）;术后随访观察组无病例被确诊为下呼吸道感染,而对照组有5例（10.0％）发生肺部感染,差异有统计学意义（x2=5.263,P＜0.05）.结论 BF可有效滤过呼吸回路细菌,显著降低老年患者全身麻醉插管术后呼吸道感染的发生率.     

5A模式在困难性下腔静脉滤器取出术围术期的应用

目的评价5A模式在困难性下腔静脉滤器(IVCF)取出术患者围术期的应用及其效果。方法选取2020年6月至2022年6月在北京积水潭医院治疗的困难性IVCF取出术患者共140例为研究对象,根据护理方法分为5A模式组(n=66)及常规护理组(n=74)。5A模式组采用5A模式护理,常规护理组采用常规护理。比较两组患者的围术期并发症发生率、自我护理能力、负性情绪、护理满意度、远期并发症发生率。结果护理实施后,5A模式组患者围术期并发症发生率低于对照组(18.18%vs 35.14%,P<0.05)。5A模式组自我护理能力各项评分均高于常规护理组(P<0.05)。实施护理后,两组HAMA、HAMD评分均低于护理前,且5A模式组汉密乐顿焦虑量表(HAMA)、汉密尔顿抑郁量表(HAMD)评分均低于常规护理组(P<0.05)。5A模式组护理满意度高于常规护理组(92.42%vs 79.73%,P<0.05)。滤器取出术6个月后,5A模式组患者远期并发症总发生率低于常规护理组(12.12%vs 18.92%,P<0.05)。结论5A模式护理应用于困难性IVCF取出术患者有利于提升患者自护能力,缓解患者负性情绪,降低并发症发生率,提升患者护理满意度。     

Clinical outcome of patients with venous thromboembolism and recent major bleeding: findings from a prospective registry (RIETE)

BACKGROUND: Patients who have experienced a recent major bleeding episode are usually excluded from clinical studies of venous thromboembolism (VTE) treatment. Therefore, recommendations based on evidence from clinical trials may not be suitable for these patients. The Registro Informatizado de la Enfermedad TromboEmbolica (RIETE) is a multicenter, observational registry designed to gather and analyze data on VTE treatment practices and clinical outcomes in patients with acute VTE. OBJECTIVES: The aim of this analysis was to study outcomes of patients with VTE who had experienced recent major bleeding (< 30 days prior to VTE diagnosis). METHODS: Patients with objectively confirmed symptomatic acute VTE are consecutively enrolled into the RIETE registry. Patient characteristics, details of antithrombotic therapy, and clinical outcomes at 3 months were recorded. RESULTS: Of 6361 patients enrolled up to January 2004, 170 (2.7%) had experienced recent major bleeding: 69 (40.6%) gastrointestinal tract, 60 (35.3%) intracranial, 41 (24.1%) other. The incidences of major bleeding (4.1%) and recurrent pulmonary embolism (PE) (2.4%) were significantly higher in patients with recent major bleeding. Among them, patients with cancer had an increased incidence of major bleeding [odds ratio (OR) 10.0, 95% confidence interval (CI) 2.3, 50; P < 0.001] and fatal PE (OR 4.1, 95% CI 0.98, 17; P < 0.05). CONCLUSIONS: Patients with VTE and recent major bleeding prior to VTE diagnosis (2.7% of total enrolled patients) had poorer clinical outcomes compared with those who had not experienced recent major bleeding. In patients who had recent major bleeding prior to enrollment, those with cancer had a poorer clinical outcome than those without cancer.     

A Compact Band-Pass Filter with High Selectivity and Second Harmonic Suppression

The design of a novel band-pass filter with narrow-band features based on an electromagnetic resonator at 6.4 GHz is presented. A prototype is manufactured and characterized in terms of transmission and reflection coefficient. The selective passband and suppression of the second harmonic make the filter suitable to be used in a C band frequency range for radar systems and satellite/terrestrial applications. To avoid substantial interference for this kind of applications, passive components with narrow band features and small dimensions are required. Between 3.6 GHz and 4.2 GHz the band-pass filter with harmonic suppression should have an attenuation of at least 35 dB, whereas for a passband, less than 10% is sufficient.     

Conversion factors for determining organ doses received by paediatric patients in high-resolution single slice computed tomography with narrow collimation

Estimations of organ doses D_T received during computed tomographic examinations are usually performed by applying conversion factors to basic dose indicators like the computed tomography dose index (CTDI) or the dose-length-product (DLP). In addition to the existing conversion factors for beam apertures of 5 mm or 10 mm, we present new DLP-D_T conversion factors adapted to high-resolution CT (HRCT) examinations of infants and young children with beam apertures of the order of 1 mm and under consideration of bow tie filtration. Calculations are performed on mathematical MIRD phantoms for an age range from 0, 1, 5, 10, 15 up to (for comparison) 30 years by adapting PCXMC, a Monte Carlo algorithm originally developed by STUK (Helsinki, Finland) for dose reconstructions in projection radiography. For this purpose, each single slice CT examination is approximated by a series of corresponding virtual planar radiographies comprising all focus positions. The transformation of CT exposure parameters into exposure parameters of the series of corresponding planar radiographies is performed by a specially developed algorithm called XCT. The DLP values are evaluated using the EGSRay code. The new method is verified at a beam aperture of 10 mm by comparison with formerly published conversion factors. We show that the higher spatial resolution leads to an enhanced DLP-D_T conversion factor if a small organ (e. g. thyroid gland, mammae, uterus, ovaries, testes) is exactly met by the chosen CT slice, while the conversion factor is drastically reduced if the chosen CT slice is positioned above or below the organ. This effect is utilized for dose-saving examinations with only a few single slices instead a full scan, which technique is applied in about 10% of all paediatric chest CT examinations.     

气管插管全麻术中预防气道感染的临床研究

目的观察一次性病毒/细菌过滤器在气管插管全麻术中预防气道感染的应用价值,为临床预防策略的制定提供参考。方法选择2011年3月-2013年3月接受气管插管全麻手术的患者76例,按照随机数字表法将其分为观察组和对照组各38例;观察组应用一次性病毒/细菌过滤器,而对照组则未用,分别在麻醉前和手术结束时用无菌棉签采集麻醉机呼气端、吸气端表面标本行细菌学检测;在手术结束时收集钠石灰罐底部10g钠石灰行细菌学检测,对比两组患者的检测结果和术后24h内气道感染发生率。结果两组患者在麻醉开始前麻醉机呼气端、吸气端细菌学培养结果均为阴性;手术结束时,麻醉机吸气端、呼气端和钠石灰的细菌学培养阳性率均为0,对照组分别为5.26%、42.11%和15.79%,观察组细菌培养阳性率均显著低于对照组,差异有统计学意义(P<0.05);术后24h内气道感染发生率观察组为2.63%,显著低于对照组的18.62%,差异有统计学意义(P<0.05)。结论麻醉机气管插管全麻可增加患者气道感染的机会,通过一次性病毒/细菌过滤器、及时更换钠石灰等措施,可有效预防气道感染的发生。     

评价一次性使用输血器具用尼龙血液过滤网过滤性能的新方法

建立一种使用240μm和160μm的标准粒子溶液评价尼龙血液过滤网过滤性能新方法,代替传统人体血液的评价方法。并通过试验证实,用该方法评价过滤网的过滤性能具有良好的重复性,操作简便、试验材料可得性强、避免因使用血液带来的安全隐患等优点。可用于尼龙血液过滤网和输血器生产的过程控制。