Evaluation of Mechanical Properties of ZY-1 Maxillofacial Prosthetic Materials

Objective Maxillofacial prosthetic materials are used to replace facial parts lost through disease or trauma. Silicone rubbers are the materials of choice. The silicone elastomer A-2186 is a widely used maxillofacial prosthetic material. It is a pourable two-component silicone rubber cured by a platinum catalyst. Used as a prosthetic material, A-2186 has short working time and good mechanical properties. The purpose of this study is to evaluate the physical properties of new prosthetic materials based on addition-type silicone elastomer （ZY-1）, and compared the mechanical properties with those of A-2186, Methods Hardness, tensile strength, ultimate elongation, tear strength and adhesive bonding strength of ZY-1 and A-2186 were compared. Statistical analyses were done using a two-way analysis of variance （ANOVA）. Results The hardness and ultimate elongation of ZY-1 is similar to A-2186. However, tensile strength, tear strength of ZY-1 were higher than those of A-2186. Conclusion ZY-1 addition-type silicone elastomer processed good mechanical properties for use as a maxillofacial prosthetic material.     

High-frequency ventilation (HFV) in hyaline membrane disease —a preliminary report

Eight premature babies affected by hyaline membrane disease and needing mechanical respiratory support were ventilated by means of a VDR 1 (Bird Space Technology) respirator at 10 Hz during a mean time of 51 h. Before HFV 7 infants had been on conventional mechanical ventilation (CMV) and one on nasal CPAP. The values of mean airway pressure (MAP) and oxygenation index (PaO₂/FIO₂) on CMV and HFV were (mean and range): 1. CMV: MAP 15 (4–29) mm Hg, ox. index 15.47 (5.07–23.19) kPa; 2. HFV after 1 h: MAP 15 (10–19) mm Hg, ox. index 24.13 (9.07–46.12) kPa. Improved oxygenation allowed rapid reduction of FIO₂ in the following hours. Only 3 infants were weaned directly from VDR 1, 5 were switched back to CMV mainly because of technical failures of the respirator. The change from HFV to CMV was associated with a fall of PaO₂/FIO₂ from 35.99 (15.86–74.52) to 22.39 (7.33–31.46) kPa. The mean time of artificial ventilation (CMV+HFV) was 121 h (range 46–166). Except for 1 pneumothorax no medical complications were seen during HFV, and all patients survived. Despite impressive improvements in oxygenation it is cautioned against the use of the VDR 1 because of the high incidence of technical problems.     

Invasive ventilation in the emergency department: Part 2: Implications for patient safety

The use of mechanical ventilation in the Emergency Department requires adequate resources in order to maintain patient safety and avoid potential risks. Moreover, developments in technology require increased knowledge of mechanical ventilation techniques to address the complexity of decision-making involved. Organisational issues and system factors have the potential to negatively impact on the ability of the emergency service to provide optimum care to patients receiving mechanical ventilation. These issues include staffing and skill-mix, demand on emergency services, role-delineation, scope of practice, and current mechanisms for monitoring of quality and safety. Furthermore, in response to advances in ventilator technology, current education programs for both nursing and medical staff require review to ensure that they provide comprehensive information about the types of ventilation techniques now available and the relative risks and benefits associated with their application.This article is the second in a two-part series and explores the educational and organisational factors that impact upon safety and quality of care delivered to patients receiving mechanical ventilation in the emergency department. Recommendations for future policy development, curriculum review and reporting mechanisms to support further research in the application of mechanical ventilation in the emergency department are made.     

无创气道正压通气治疗心力衰竭疗效观察

目的:探讨无创气道正压通气对心力衰竭患者的疗效。方法:将我院住院的86例心力衰竭患者随机分为治疗组(药物常规治疗的基础上运用机械通气)44例和对照组(常规药物治疗组)42例。两组患者性别、年龄、病情情况均无统计学意义。治疗组在药物常规治疗的基础上运用机械通气。结果:两组治疗后,心衰症状、心脏功能指标,血气指标均有改进。但治疗组较对照组改进更明显,与对照组比较差异有显著意义(P<0.01)。结论:无创气道正压通气能增加心脏射血,改善心功能、提高心衰患者生存率。     

院前紧急气管插管与机械通气24例临床分析

目的总结紧急气管插管与机械通气在院前急救中应用的经验,以期提高院前急救水平。方法回顾性分析24例院前气管插管与机械通气抢救心搏呼吸骤停病人的临床资料。结果24例病人气管内插管均获成功,成功率100%。完成气管内插管的时间是15s～60s,平均时间(25±15)s。心搏、自主呼吸恢复4例(16.7%),心搏恢复8例(33.3%);心搏及自主呼吸均未恢复12例(50.0%)。结论气管插管与机械通气是急诊抢救危重病人的基础,对保证进一步心肺复苏、挽留手术机会以及提高危重患者抢救成功率有重要意义。要加强对抢救人员进行紧急气管插管和机械通气的培训。     

一种新型的声门外通气设备——喉导管

喉导管是一种新型的声门外通气设备.在气道的建立和维持上和喉罩相比有相似的优缺点.喉导管和喉罩总的插管成功率相近,一次插管成功率喉导管要远远高于喉罩.喉导管的气道封闭性更好.喉导管可用于四肢、泌尿、妇科和躯干体表手术以及困难气道的插管.在喉部空间狭小患者和颈髓损伤患者气道的建立上比喉罩更有优势,亦可用于心肺复苏时紧急气道的建立.     

机械通气致下呼吸道黄杆菌感染的临床分析

目的:探讨黄杆菌属致下呼吸道感染的临床特点及对常用抗生素的耐药情况。方法:分析我院六年来机械通气致下呼吸道黄杆菌感染的11例临床资料,平板稀释法测定常用抗菌药物对该菌株的最低抑菌浓度,采用法国生物梅里埃公司API系统进行细菌学鉴定,以美国国家实验室标准化委员会NCCLS的标准判定结果。结果:全部应用广谱抗生素,年龄>60岁者8例,机械通气到发生黄杆菌感染的平均时间为18天,死亡4例;耐药率高,仅对头孢哌酮/舒巴坦、复方磺胺甲恶唑、哌拉西林、左氧氟沙星等较敏感。结论:机械通气致下呼吸道黄杆菌感染常发生在基础状态较差,机械通气时间较长,且长期应用广谱抗生素的老年患者,临床表现常无特征性,细菌耐药严重,病死率高     

BiPAP ViSION 在慢性阻塞性肺疾病Ⅱ型呼吸衰竭的应用和护理

目的 探讨经鼻(面)罩双水平气道内正压通气(BiPAP)ViSION型呼吸机对慢性阻塞性肺疾病(COPD)伴Ⅱ型呼吸衰竭患者疗效及护理特点。方法 应用BiPAP ViSION型呼吸机对21例COPD伴Ⅱ型呼吸衰竭患者采用鼻/面罩连接单向呼气活瓣行双水平气道正压通气,观察其通气前后动脉血气及临床表现变化。结果 通气治疗后19例患者动脉血氧分压(PaO_2)及氧饱和度(SaO_2)明显升高(P<0.01),二氧化碳分压(PaCO_2)显著降低(P<0.05);肺性脑病症状消失,昏迷患者神志转清。2例病情恶化,其中1例改用有创通气后好转,1例拒绝有创通气死亡。结论BiPAP ViSION呼吸机治疗COPD伴Ⅱ型呼吸衰竭的疗效较为肯定,正确的护理对提高其疗效和减少并发症至关重要。     

两种剂量氟碳部分液体通气治疗犬吸入伤的比较研究

目的：对比研究两种剂量氟碳（PFC）部分液体通气（PLV）对蒸气吸入性损伤犬的血气和血流动力学的影响，方法：将健康犬15条随机分面两组，即PFC6ml/kg组（PFC－6）和PFC 12ml/kg(PFC-12)组，采用蒸气吸入造成吸入性损伤模型后经气管内注入PFC实施部分液体通气（PLV）治疗，观察治疗后30min,60min,90min血气，血流动力学参数的变化，结果：PFC－6组PaO2在PLV治疗30min后明显升高（P＜0．05），在治疗60min,90min生的PaO2与致伤值比较无统计学意义，而PFC－12组的PaO2在PLV治疗后30min,60min,90min均明显升高（P＜0．05），与PFC－6组相比，PFC－12组的PaO2,PvO2均呈上升趋势，但未达显著水平（P＞0．05），在PLV治疗后各时间点的PaCO2HR,MAP,CVP 致伤值相比均无明显变化（P＞0．05），两组之间比较，各对应时间点的PaCO2,HR,MAP,CVP也均无明显变化（P＞0．05），结论：氟碳部分液体通气是一种新的通气技术，它能明显改善蒸气入伤犬的氧合作用，对血液动力学参数无不良影响，两种剂量氟碳部分液体通气治疗蒸气吸入性损伤未呈现明显剂量一效应关系。     

无创正压通气不同压力支持水平对正常人呼吸做功的影响

目的 :观察无创正压通气 (NIPPV)不同压力水平对正常人呼吸做功的影响 ,为临床合理地应用NIPPV提供理论依据。方法 :选择 9例正常人行NIPPV并寻找出“最舒适”的吸气压力水平 (IPAP) ,在此压力基础上增加或减少 2 5 %的压力 ,构成低IPAP、最舒适IPAP和高IPAP三个压力水平 ,每一IPAP水平通气 15min以上 ,比较不同压力水平呼吸做功改变。结果 :受试者认为“最舒适”的IPAP为 (11.33± 3.2 0 )cmH2 O ,EPAP为 (4 .5 6± 0 .88)cmH2 O[相当于PSV水平为 (6 .77± 3.2 0 )cmH2 O]。与自主呼吸相比 ,NIPPV增加VE的同时 ,总的呼吸做功(Wtot)明显增加 (P <0 .0 5 ) ,而受试者吸气肌做功占总的吸气做功的百分比 (Wi,p/Wi)明显减少 (P <0 .0 5 )。在最舒适IPAP时 ,Wi,p/Wi降低到基础值的 14 %± 9%。这种变化趋势与IPAP的水平相关。结论 :NIPPV可以显著降低吸气肌肉做功。吸气肌做功减少的比例与IPAP的水平相关。研究的结果为NIPPV时PSV的参数设定提供了生理学的依据。