呼吸机管道更换时间与呼吸机相关性肺炎发生的相关性探讨

目的通过呼吸机管道更换时间与呼吸机相关性肺炎(VAP)发生的相关性的研究,探索呼吸机管道最佳更换时间,对机械通气患者实施最佳护理。方法将60例ICU机械通气患者随机分为实验组和对照组,分别予以每7 d和每2 d更换呼吸机管道,两组患者每周行2次痰液培养,1次床边胸片,观察2周内有无VAP发生。结果两组VAP的发生率差异无显著意义(P0.05)。结论就护理成本以及对患者心理和生理的影响考虑,每7 d更换呼吸机管道比每2 d更换更合适。     

热湿交换器和加温湿化器对呼吸机相关性肺炎发生率影响的荟萃分析

目的 探讨热湿交换器(HME)与加温湿化器(HH)是否可降低机械通气患者呼吸机相关性肺炎(VAP)的发生。方法 通过计算机检索和手工检索PubMed、Cochrane数据库,收集1990年1月1日至2010年9月1日关于HME与HH对机械通气患者VAP影响的随机对照研究(RCT),按Cochrane协作网推荐的方法,对HME与HH预防机械通气患者VAP的发生率进行荟萃分析(Meta分析)。结果 共纳入11篇RCT文献,其中HME组1 121例,HH组1 101例,两组VAP发生率分别为14.2％(159/1 121)和15.9％(175/1 101),相对危险度(RR)=0.88,95％可信区间(95％CI)0.72～1.07,P=0.21,表明与HH相比,HME并不降低机械通气患者VAP的发生率。筛选机械通气时间＞7 d的RCT进行亚组分析,共纳入8篇文献,其中HME组834例,HH组859例,VAP发生率分别为15.2％(127/834)和17.5％(150/859),RR=0.84,95％CI0.58～1.23,P=0.37,表明在机械通气时间＞7d的患者中,HME同样不降低VAP的发生率。结论 HME并不降低机械通气患者VAP的发生率,即使在机械通气时间超过7d的患者也是如此。由于有关的RCT数量相对较少、质量较低（缺少盲法）,需要高质量的大规模RCT进一步证实。     

不同机械通气管道更换时间对细菌检查及呼吸机相关性肺炎的影响

目的:探讨不同机械通气管道更换时间对细菌学检查及呼吸机相关性肺炎(VAP)的影响。方法:2014年6月~2015年3月我院ICU收治60例患者,将2014年6~10月住院的30例患者设为对照组,呼吸机管道更换时间为每7 d更换1次;将2014年11月~2015年3月入院的30例患者设为观察组,更换时间为每9 d更换1次,比较机械通气第1天、第4天、第7天、第9天、第11天下呼吸道分泌物、呼吸机管路吸气端、呼气端、螺纹管近端内侧面细菌培养结果,比较两组患者VAP的发生情况及细菌污染情况。结果:观察组VAP发生情况与对照组比较差异无统计学意义(P0.05),观察组与对照组患者机械通气第1天、第4天、第7天、第9天及第11天的细菌污染情况比较差异无统计学意义(P0.05)。结论:ICU患者每7 d与每9 d更换管道频率对VAP发生频率无明显影响,建议可每9 d更换1次。     

观察机械通气患者呼吸机管路细菌污染以及对呼吸机相关性肺炎的影响北大核心CSCD

目的：观察重症监护病房（ ICU）内机械通气患者呼吸机管路细菌污染状态以及呼吸机管路更换对呼吸机相关性肺炎（ VAP）发生率的影响,为合理进行呼吸机管路管理提供依据。方法将ICU内161例机械通气患者根据换管时间分组,其中81例患者每天分别进行呼吸机管路不同部位细菌培养、痰培养,比较细菌生长率的情况;对不同组间VAP的发生率及预后进行比较。结果呼吸机管路细菌以革兰阴性菌为主,管路与人工气道接口处细菌生长率（84．65％）最高（P＜0．01）,进气管路细菌培养与痰培养一致率（41．49％）较低（P＜0．01）;呼吸机进气管路、出气管路、与人工气道接口处细菌生长均与时间呈正相关,相关系数（ r）分别为0．9694、0．9082、0．6384。细菌生长的时间先后顺序依次为人工气道接口处、出气管路、进气管路。不同换管时间患者VAP的发生率及预后比较差异无统计学意义（P＞0．05）。结论机械通气患者呼吸机管路细菌污染率高,但调整更换呼吸机管路的更换周期对VAP的发生率无影响。     

密闭式吸痰装置更换频率对呼吸机相关性肺炎影响的Meta分析

目的 系统评价密闭式吸痰装置更换频率对呼吸机相关性肺炎的影响。方法 计算机检索PubMed、EMBASE、Cochrane Library、中国期刊全文数据库、中国生物医学文献数据库、万方数据库中有关密闭式吸痰装置更换频率的随机对照试验,由2名研究者独立对获得文献进行筛查、质量评价和资料提取,采用Revman 5.3软件进行Meta分析。结果 最终纳入7篇随机对照试验,共1098例患者,Meta分析结果显示,每48h及以上与每24h更换密闭式吸痰装置相比,呼吸机相关性肺炎发生率的差异无统计学意义（P>0.05）;亚组分析显示,每48h、每72h或每120h更换密闭式吸痰装置对呼吸机相关性肺炎发生率的影响,差异无统计学意义（P>0.05）;每72h及以上更换的密闭式吸痰装置尖端菌群定植率高于每24h更换组（P<0.05）;密闭式吸痰装置更换频率对于患者的机械通气时间、ICU住院日、病死率均无影响（P>0.05）。结论 密闭式吸痰装置的更换频率对呼吸机相关性肺炎的发生率无影响,但超过72h更换,密闭吸痰装置尖端细菌定植率显著增加,建议临床每72h更换密闭式吸痰装置以减少尖端细菌定植,预防进一步感染。     

刷牙对机械通气病人呼吸机相关性肺炎发生率影响的Meta分析

[目的]评价刷牙对行机械通气病人呼吸机相关性肺炎(VAP)发生率的影响。[方法]采用Cochrane系统评价方法,检索国内外相关文献,纳入符合标准的随机对照试验(RCT)和类实验性研究(CCT)进行Meta分析。[结果]共纳入19篇RCT和1篇CCT。Meta分析结果显示,对于行机械通气的病人给予刷牙能有效降低呼吸机相关性肺炎的发生率,同时还可以降低牙菌斑指数、缩短机械通气时间及ICU住院时间、降低病死率以及减少口腔疾病的发生率等。[结论]行机械通气的病人给予刷牙不仅能有效降低VAP的发生率,还可缩短住院时间。     

腹腔感染患者呼吸机管路不同消毒时间对细菌定植的影响

目的 探讨以收治腹腔感染患者为主的ICU呼吸机管路的更换时间,降低因呼吸机管路内细菌定植引起的VAP发生率.方法 将2008年1月至2009年6月入住ICU病房机械通气时间＞48 h且APACHEⅡ≥8分的90例患者,随机分为A、B、C 3组各30例,分别在使用前及使用后1,3,7 d对呼吸机管路吸气端采样留取培养标本,行细菌培养加菌种分析,使用后呼吸机管路采样均在管路更换前30 min进行.结果 3组患者使用前的呼吸机管路培养均为无菌生长,使用后1,3,7 d的细菌培养阳性率分别为46.66%、53.33%和100.00%.结论 腹腔感染行机械通气治疗的患者,呼吸机管路的更换间隔时间应当缩短,3d更换呼吸机管路适合于收治感染患者为主的ICU病房.     

腹腔感染患者呼吸机管路不同消毒时间对细菌定植的影响

目的 探讨以收治腹腔感染患者为主的ICU呼吸机管路的更换时间,降低因呼吸机管路内细菌定植引起的VAP发生率.方法 将2008年1月至2009年6月入住ICU病房机械通气时间＞48 h且APACHEⅡ≥8分的90例患者,随机分为A、B、C 3组各30例,分别在使用前及使用后1,3,7 d对呼吸机管路吸气端采样留取培养标本,行细菌培养加菌种分析,使用后呼吸机管路采样均在管路更换前30 min进行.结果 3组患者使用前的呼吸机管路培养均为无菌生长,使用后1,3,7 d的细菌培养阳性率分别为46.66%、53.33%和100.00%.结论 腹腔感染行机械通气治疗的患者,呼吸机管路的更换间隔时间应当缩短,3d更换呼吸机管路适合于收治感染患者为主的ICU病房.     

呼吸机管路低位摆放联合口鼻腔冲洗干预在肺炎机械通气中的应用效果观察

目的 观察呼吸机管路低位摆放联合口鼻腔冲洗干预在肺炎机械通气中应用效果。方法 选取2019年1月至2022年5月我院收治的需机械通气的肺炎患者60例,采用简单随机法分为正常组和观察组各30例。正常组机械通气中采用口鼻腔冲洗干预,观察组机械通气中采用呼吸机管路低位摆放联合口鼻腔冲洗干预。比较两组患者有创通气时间、ICU住院时间及误拔管、呼吸机相关性肺炎(VAP)、28 d病死发生率,检测两组干预前及干预3、7 d降钙素原(PCT)、白细胞计数(WBC)等炎症因子的变化。结果 观察组有创通气时间、ICU住院时间明显短于正常组,冷凝液倒流和VAP发生率明显低于正常组(P<0.05);两组28 d病死率、累计误拔管发生率、临床总有效率比较,差异无统计学意义(P>0.05);干预3、7 d后两组PCT、WBC、肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)明显较干预前下降,且观察组炎症因子指标低于正常组(P<0.05)。结论 呼吸机管路低位摆放联合口鼻腔冲洗干预可降低肺炎机械通气中冷凝液倒流发生率,缩短病程,降低VAP的发生。     

ICU复用性呼吸机管路清洗消毒现状及研究进展

机械通气是现阶段临床抢救呼吸衰竭病人的主要手段,但它在起到重要作用的同时也存在很多问题,如呼吸机相关性肺炎(Ventilation-associated pneumoniaVAP).在机械通气过程中,呼吸机的复用性管路是重要感染源,有研究显示:使用7d的呼吸机管路细菌菌落数为3.75～7.5万cf u/cm,细菌培养阳性率为100％[1-2].因此,近年来各大医院对呼吸机复用性管路的清洗、消毒也进行了诸多探讨,但尚未有统一的方法.笔者将从不同方面介绍呼吸机管路的清洗消毒方法及近几年的研究进展,以期各医院能用适合自己的方法降低VAP的发生率.     

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.