机械通气患者呼吸过滤器更换时间的研究

目的探讨呼吸过滤器(BF)的最佳更换时间。方法将40例机械通气患者随机分为亲水型BF组每组各20例与复合型BF组每组各20例。在患者机械通气开始时,将BF连接在气管导管与呼吸机螺纹管Y形管接头之间;在患者机械通气后的第1~5 d,每天对两组患者BF滤过膜的呼吸机侧采样并进行细菌培养。结果亲水型BF组细菌培养阳性率第1 d均为0,第2、3、4、5 d细菌培养阳性率为60%、75%、100%和100%,复合型BF组细菌培养阳性率第1、2 d均为0,第3、4、5 d细菌培养阳性率为25%、70%和100%,两组不同采样时间细菌培养阳性率比较,第2、3、4 d比较有统计学意义(P0.05);两组细菌鉴定种类比较无差异,无统计学意义(P0.05)。结论亲水型BF的更换时间以1次/d适宜,复合型BF的更换时间以1次/2 d适宜,复合型过滤器滤菌效应较亲水型好,不同型号BF的更换与细菌的种类无关。     

机械通气病人呼吸过滤器更换时间的临床研究

[目的]探讨呼吸过滤器(BF)的最佳更换时间。[方法]将40例机械通气病人随机分为亲水型BF组(n=20)与复合型BF组(n=20)。在病人机械通气开始时,将BF连接在气管导管与呼吸机螺纹管Y形管接头之间;在病人机械通气后的第1天~第5天,每天对两组病人BF滤过膜的呼吸机侧采样并进行细菌培养。[结果]亲水型BF组细菌培养阳性率第1天均为0,第2天、第3天、第4天、第5天细菌培养阳性率分别为60%、75%、100%、100%,复合型BF组细菌培养阳性率第1天、第2天均为0,第3天、第4天、第5天细菌培养阳性率分别为25%、70%、100%,两组不同采样时间细菌培养阳性率比较,第2天、第3天、第4天比较差异有统计学意义(P0.05);两组细菌鉴定种类比较差异无统计学意义(P0.05)。[结论]亲水型BF的更换时间以每天1次为宜,复合型BF的更换时间以2d1次为宜,复合型过滤器滤菌效应较亲水型好,不同型号BF的更换与细菌的种类无关。     

机械通气病人呼吸过滤器更换时间的临床研究

[目的]探讨呼吸过滤器（BF）的最佳更换时间。[方法]将40例机械通气病人随机分为亲水型BF组（n=20）与复合型BF组（n=20）。在病人机械通气开始时,将BF连接在气管导管与呼吸机螺纹管 Y形管接头之间;在病人机械通气后的第1天-第5天,每天对两组病人BF滤过膜的呼吸机侧采样并进行细菌培养。[结果]亲水型 BF组细菌培养阳性率第1天均为0,第2天、第3天、第4天、第5天细菌培养阳性率分别为60%、75%、100%、100%,复合型BF组细菌培养阳性率第1天、第2天均为0,第3天、第4天、第5天细菌培养阳性率分别为25%、70%、100%,两组不同采样时间细菌培养阳性率比较,第2天、第3天、第4天比较差异有统计学意义（P〈0.05）;两组细菌鉴定种类比较差异无统计学意义（P〉0.05）。[结论]亲水型 BF的更换时间以每天1次为宜,复合型 BF的更换时间以2 d 1次为宜,复合型过滤器滤菌效应较亲水型好,不同型号BF的更换与细菌的种类无关。     

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.     

呼吸过滤器对麻醉呼吸回路滤菌作用的临床观察

目的观察呼吸过滤器对麻醉呼吸回路的滤菌作用。方法择期全麻手术患者60例 ,随机分为2组 ,实验组的气管导管与呼吸回路之间放置呼吸过滤器。于麻醉前、麻醉结束时对气管导管末端、呼吸回路气管端采样作细菌培养计数 ,并对手术室空气采样行细菌培养。结果麻醉结束后对照组呼吸回路中有大量细菌存在 ,而实验组无细菌发现(P<0.01)。结论呼吸过滤器能有效虑过患者呼吸道及呼吸回路中细菌 ,减少患者医源性肺部感染     

双伺服性加温控制型呼吸湿化器的应用对呼吸道与呼吸机回路细菌定植的影响

[目的]分析双伺服性加温控制型呼吸湿化器对呼吸道与呼吸机管道细菌定植的影响,为规范呼吸机管道更换周期、预防呼吸机相关性肺炎提供参考。[方法]选择重症医学科建立人工气道机械通气72h以上106例病人,使用伺服性加温控制型呼吸湿化器,分别于建立人工气道上机当天及应用第3天、第7天、第10天、第14天、第21天、第28天采样,采样部位分别为病人的咽喉部、下呼吸道、呼吸机接头端、呼吸机管道吸气端、呼吸机管道呼气端、湿化罐湿化液;对采样标本进行细菌培养,分离致病菌,比较不同时间段、不同部位致病菌的阳性率、定植率。[结果]呼吸机管道的定植菌与呼吸道病原菌具有同源性;呼吸道相同部位不同采样时间的致病菌检出率差异有统计学意义(P0.05),呼吸机管道相同部位不同采样时间的致病菌检出率差异无统计学意义(P0.05)。[结论]延长使用双伺服性加温控制型呼吸湿化器至28d,呼吸道细菌随着机械通气时间的延长细菌定植增加,而呼吸机管道系统随机械通气时间的增加细菌定植无明显增加;使用双伺服性加温控制型呼吸湿化器无污染的情况下持续使用是安全的,对长期使用呼吸机的病人呼吸机管道无需常规更换,对有污染或故障的呼吸机管道应及时更换。     

应用HME对呼吸机辅助呼吸病人呼吸机内部气路管道无菌状态的影响

[目的]比较人工气道使用呼吸机辅助呼吸病人中应用复合式人工鼻过滤器(HME)加细菌过滤器和单纯应用HME的临床效果。[方法]选择入住ICU建立人工气道使用呼吸机辅助呼吸72h以上、使用呼吸机辅助呼吸24h、痰培养为阳性的病人61例,随机分为HME加细菌过滤器组31例和HME组30例。观察两组主机内部气路管道系统细菌阻隔情况,比较两组费用和护理时数。[结果]HME加细菌过滤器组与HME组细菌过滤效果比较差异无统计学意义(P0.05),两组项目费用及护理时数比较差异有统计学意义(P0.01)。[结论]单纯应用HME与应用HME加细菌过滤器效果相同,但具有降低医疗费用、减轻病人经济负担、减少护理工作时数、提高工作效率等优点,是维持呼吸机内部气路无菌状态的经济、简单、有效、实用的方法。     

麻醉术后ICU病人机械通气的监测与护理

本文认为，对于麻醉术后带气管导管进入ＩＣＵ的病人机械通气期间，应从以下几方面加强监测与护理：①对病人的全身情况观察以了解病情的变化；②对气管插管及气管切开的病人要加强气道的管理，进行气道内雾化及冲洗，以保持呼吸道的通畅；③合理调节呼吸机的各项参数，观察机械通气的效果，改善呼吸功能。     

气管插管全麻手术相关的消毒管理研究

目的观察气管插管全麻手术医院内下呼吸道感染的相关因素,作好消毒管理。方法采用现场采样和实验室检验方法,对麻醉机内部元件及相关麻醉用品自然菌污染和人工菌杀灭效果进行了检测。结果患者呼出的气体经过一次性病毒/细菌过滤器过滤后进入呼吸回路的管道,细菌明显减少,一次性呼吸回路管道未能检出细菌。麻醉机内部的螺纹管、气阀均未检出致病菌。麻醉机内部的二氧化碳吸收剂(钠石灰)对细菌繁殖体、结核分枝杆菌和细菌芽孢均具有一定杀灭作用。结论麻醉用品的病毒/细菌过滤器对进入病人的呼吸道微生物具有一定过滤效果,管路中的二氧化碳吸收剂具有一定杀菌作用。     

高位截瘫有创通气的气道护理

高位截瘫病人常伴有咳嗽无力,无咳嗽反射,甚至伴有呼吸肌无力,导致病人出现血氧饱和度降低、呼吸困难、肺部感染,这时往往需要通过有创通气,即气管切开,建立人工气道,改善病人通气功能。气管切开后呼吸道直接与外界相通,失去了自身保护性的空气滤过作用,极易引起肺部感染等并发症,而高效的气道护理,     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.