心包积液时呼吸对血流动力学影响的超声心动图研究

目的　观察心包积液时呼吸性胸压变化对血流动力学的影响 ,从临床角度验证笔者提出的关于呼吸影响心功能机制新假说 ,提出心包积液时血流动力学改变程度参考指标。方法　 10例大量心包积液患者 ,采用AcusonSequoia 512和 12 8XP/ 10型超声仪 ,同步记录各瓣口血流速率、心电图和呼吸曲线。分别于呼气相和吸气相连续测量 5个呼吸周期的各瓣口血流速率 ,并分别取呼气相和吸气相平均值 ,计算呼吸性血流速率波动指数 (RVI) ,并与 18例健康志愿者的结果进行比较分析。结果　心包积液组二尖瓣(MV)E峰血流速率RVI值和主动脉瓣 (AV)血流速率RVI值均较正常组明显增大 [MV :(14 .57± 7.89) %对 (9.71± 3 .3 9) % ,P <0 .0 5;AV :(11.61± 4.96) %对 (4.67± 1.79) % ,P <0 .0 0 1] ;三尖瓣 (TV)E峰血流速率RVI值和肺动脉瓣 (PV)血流速率RVI值也均较正常组显著增大 [TV :(2 4.97%± 6.19) %对 (14 .82± 3 .70 ) % ,P <0 .0 0 1;PV :(2 3 .93± 10 .12 ) %对 (5.86± 2 .55) % ,P <0 .0 0 1]。结论心包积液时呼吸性胸压变化对心脏各瓣口血流速率影响明显增大 ,RVI值可以作为心包积液和心包填塞严重程度的衡量指标 ;心包腔内压是决定呼吸对血流动力学影响程度的因素之一     

呼吸对慢性阻塞性肺疾病心脏血流动力学影响的超声心动图研究

目的用超声心动图方法检测慢性阻塞性肺疾病(COPD)患者自然呼吸过程中心脏各瓣口血流速度随呼吸的变化,探讨自然呼吸对COPD患者心功能影响的机制及临床意义。方法采用AcusonSequoia512彩色超声仪记录20例COPD患者和30例健康人自然呼吸时心脏各瓣口血流速度,同步记录心电图和呼吸曲线,计算各瓣口的血流速度呼吸性波动指数(RVI)。结果COPD组与健康对照组均表现为二尖瓣E峰血流速度和主动脉瓣血流速度在呼气相高于吸气相(P<0.001),三尖瓣E峰血流速度和肺动脉瓣血流速度在吸气相高于呼气相(P<0.001)。COPD组心脏各瓣口血流速度RVI较对照组均明显增大[二尖瓣(16.26±8.71)%对(10.53±3.15)%,P<0.03;主动脉瓣(11.61±4.96)%对(4.67±1.79)%,P<0.001;三尖瓣(27.74±8.39)%对(14.89±6.32)%,P<0.001;肺动脉瓣(13.78±4.98)%对(8.55±2.32)%,P<0.001]。结论COPD组与健康对照组自然呼吸时心脏各瓣口血流速度随呼吸时相波动的变化规律一致,但COPD组四个瓣口RVI较健康对照组明显升高,进一步证明了呼吸性胸压变化可以导致心脏各瓣口血流速度变化。该结果对COPD患者肺实质损伤程度的判定以及治疗效果的追踪观察有重要参考价值。     

平静呼吸对正常人心内血流速度影响的超声心动图研究

目的　研究呼吸对心脏血流动力学的影响 ,为建立我国正常人呼吸性血流速度波动指数 (RVI)提供参考 ,验证呼吸影响心功能新假说。方法　 79名健康志愿者 ,采用AcusonSequoia 5 12和 12 8XP/10彩色电脑声像仪 ,记录各瓣口血流速度、同步心电图和呼吸曲线。不同呼吸相所测的各瓣口血流速度分别取平均值 ,计算RVI。结果　二尖瓣E峰血流速度和主动脉瓣血流速度在呼气相均高于吸气相 [( 83.79± 17.74)cm/svs ( 76.5 5± 15 .5 0 )cm/s ,P <0 .0 0 0 1;( 10 9.36± 14 .0 9)cm /svs ( 10 4.2 2± 13.75 )cm/s ,P <0 .0 0 0 1] ;三尖瓣E峰血流速度和肺动脉瓣血流速度在吸气相高于呼气相 [( 62 .19± 17.2 1)cm/svs ( 5 2 .79± 14 .10 )cm/s ,P <0 .0 0 0 1;( 89.80± 15 .78)cm/svs ( 84.76± 15 .0 3)cm /s ,P <0 .0 0 0 1]。二、三尖瓣 ,主、肺动脉瓣的RVI均值分别为8.39%、16.40 %、4.71%和 5 .73%。结论　平静呼吸对心脏血流动力学影响具有规律性。RVI可作为评定呼吸影响心功能的客观指标 ,为呼吸影响心功能假说提供了临床实验依据     

呼吸对正常犬血流动力学影响的超声心动图研究

目的研究正常自主呼吸胸压变化对血流动力学的影响,进一步探讨呼吸影响心功能的机制.方法 11条心功能正常杂种犬,使用Acuson Sequoia 512彩色电脑声像仪,同步记录心电图、呼吸曲线和心内各瓣口血流速度,观察瓣口血流速度随呼吸变化的规律.结果三尖瓣和肺动脉瓣口血流速度随呼吸周期呈现规律性变化,但二尖瓣和主动脉瓣口的血流在部分呼吸周期中的变化并无明显规律,峰值血流速度出现与呼吸时相间有不确定性.结论自主呼吸所引起的胸压变化使室间隔左右摆动,但由于肺组织本身弹性的差异,胸内压和肺毛细血管内压间存在的压差使全胸内系统血液重新分布.这种血液重新分布取决于肺组织的弹性,从而导致二尖瓣和主动脉瓣口血流速度变化与呼吸时相间具有不确定性.     

超声心动图研究正压通气对犬心功能的影响及其机制

目的观察正压通气时心内瓣口血流速度和左、右心功能的变化,研究正压通气影响血流动力学机制的新理论。方法11条杂种犬,用超声心动图测定正压通气时心内各瓣口的血流速度,右室、左室每搏量,左室容积和射血分数的变化。结果三尖瓣和肺动脉瓣口血流速度正压吸气相减低,呼气相增加;二尖瓣和主动脉瓣口血流速度变化与之相反(P<0.05)。与自主呼吸相比,正压吸气时,右室每搏量减少,左室舒张末和收缩末容积减小,射血分数降低(P<0.05)。结论正压通气使室间隔趋于右移,同时,肺血管床回心血量增加,但与自主呼吸时相比,腔静脉回心血量相对减少,故心功能降低。     

超声心动图观察室间隔运动新方法研究

目的 利用室间隔运动时曲率半径的变化,观察正常人呼吸性胸压变化对室间隔摆动和形变的影响,评价新方法 观察室间隔运动的敏感性.方法 应用Acuson Sequoia 512型超声仪对21例健康志愿者进行检查.分别获取呼气相和吸气相左室腱索短轴观图像;同步记录各瓣口血流速率、心电图和呼吸曲线.两名医师在双盲条件下采用自制的测量软件.分别测量吸气相与呼气相室间隔曲率半径.结果 二尖瓣E峰血流速率和主动脉血流速率在呼气相均高于吸气相;三尖瓣E峰血流速率和肺动脉瓣血流速率则相反.吸气相室间隔曲率半径为(25.14±6.082)mm.呼气相室间隔曲率半径为(22.296±4.398)mm,二者差异有统计学意义(P<0.0001).结论 曲率半径可以评估室壁摆动和形变,具有良好的重复性,为临床评价呼吸性胸压变化提供一种敏感而可靠的新方法 .     

呼吸对慢性阻塞性肺病左心室充盈的影响及其机制的超声心动图研究

目的探讨超声心动图检测慢性阻塞性肺病（COPD）患者左心室功能和COPD病程的可行性。方法采用Sequoia512彩色超声诊断仪,记录21例COPD患者及50名健康人自然呼吸时二尖瓣口E峰、A峰血流速度,同步记录心电图和呼吸曲线,计算二尖瓣舒张早期E峰血流速度呼吸性波动指数（RVI）及E峰与A峰血流速度比值（E/A）呼吸变化率。结果两组均表现为E峰血流速度、E/A吸气相低于呼气相（P〈0.001）;COPD组A峰血流速度吸气相与呼气相差异无统计学意义（P=0.076）,而健康对照组A峰血流速度吸气相低于呼气相（P〈0.001）。COPD组二尖瓣E峰血流速度RVI及E/A呼吸变化率均较对照组增大（P=0.002）。结论自然呼吸对COPD患者二尖瓣血流影响具有规律性,进一步验证了呼吸影响心功能机制新假说,同时也为利用多普勒技术评价COPD患者左室功能损害程度和肺实质病变严重程度的进一步研究提供更多信息。     

胸压对三尖瓣反流速度和肺动脉压测定的影响

目的 应用超声心动图观察平静呼吸情况下胸压对三尖瓣反流速度的影响及规律,为超声心动图准确测定肺动脉压和验证呼吸影响心功能机制新假说提供依据.方法 对50例三尖瓣反流患者,利用二维及多普勒超声心动图记录不同呼吸时相三尖瓣反流速度和跨瓣压,观察不同呼吸时相时三尖瓣反流速度的变化规律.结果 呼吸对三尖瓣反流速度有确定影响,反流速度与呼吸时相关系表现有三种类型:第一种为吸气相速度增加,呼气相速度减小;第二种表现与第一种相反;第三种为速度变化表现为随机性.结论 呼吸性胸压变化对三尖瓣反流速度有明确影响,提示用多普勒法无创测定肺动脉压时需要将呼吸停止在呼吸时相的中期,并保持测定过程中胸压稳定,以提高测定准确性.     

多普勒组织显像评价左心室舒张功能：二尖瓣环运动速度

本文采用多普勒组织显像(DTI)检测了30例正常人和59例高血压病人舒张期二尖瓣瓣环运动速度频谱,并与二尖瓣瓣口血流频谱进行比较。结果发现:二尖瓣瓣环DTI速度频谱为负向双峰,正常人组e峰均高于a峰,高血压组e峰低于a峰,高血压组a/f值均大于1.0,明显高于正常人组(P<0.05);高血压组内DTI速度频谱较二尖瓣瓣口血流频谱类型单一,两者a/e值和A/E值之间有显著性差异(P<0.05),相关系数低(r=0.29)。结果表明:二尖瓣瓣环DTI速度频谱可以反映左心室舒张功能变化,较二尖瓣瓣口血流频谱敏感且影响因素少,是一项有前途的左心室舒张功能评价方法。     

平静呼吸对室间隔缺损左向右分流影响的超声心动图研究

目的应用超声心动图检测室间隔缺损（VSD）患者平静呼吸过程中室水平左向右分流血流速度随呼吸的变化,探讨平静呼吸对VSD患者心功能影响的机制及其临床意义。方法超声记录28例VSD患者平静呼吸时室水平左向右分流的血流速度,同步记录心电图和呼吸曲线。结果平静呼吸时,VSD患者室水平左向右分流的血流速度均于吸气相低于呼气相。结论VSD患者平静呼吸时室水平左向右分流的血流速度随呼吸时相波动而规律性变化,证明了呼吸性胸压变化是导致室间隔缺损分流速度波动性变化的主要原因。     

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.     

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.     

手转胎头术失败的原因与分娩结局临床分析

目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4％(55/72)]明显高于成功组[31.7％(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3％(42/72)]高于成功组[38.1％ (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9％ (28/72)]高于成功组[23.8％(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大＜6 cm、胎头位于坐骨棘上及宫口开大8～10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1％(44/72)]高于成功组[38.9％(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2％(52/72)]明显高于成功组[34.1 ％(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.     

Evidence-Based Pain Management and Palliative Care in Issue Four for 2009 of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly. Issue 4 for 2009 contains 4027 complete reviews, 1906 protocols for reviews in production, and 11447 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 600,000 randomized controlled trials, and 12,200 cited papers in the Cochrane methodology register. The health technology assessment database contains over 7500 citations. This edition of the Library contains 90 new reviews, of which 19 have potential relevance for practitioners in pain and palliative medicine.     

Wie zuverlässig sind Angaben zu nichtentzündlichen ausgedehnten Schmerzen?

ZusammenfassungFragestellung Es wurde geprüft, wie sich der Differenziertheitsgrad zweier Schmerzmessmethoden auf Angaben zur Ausgedehntheit klinischer Schmerzen auswirkt. Zugleich wurde der Referenzzeitraum variiert, über den die Patienten berichten sollten.Methode Erfasst wurde der Einfluss zu Lasten der Befragungsdifferenziertheit durch den Vergleich zweier Körperschema-Bildvorlagen. Drei Referenzzeiträume (Schmerz aktuell, letzte Woche, letztes halbes Jahr) wurden vorgegeben.Ergebnisse Patienten mit ausgedehnten Schmerzen gaben bei differenzierter Befragung um so mehr Schmerzen an, je weiter die Schmerzen zurück lagen und je größer der Berichtszeitraum war. Patienten mit gelenknahen Schmerzen gaben bei hoch differenzierter Befragung weniger ausgedehnte Schmerzen in der Vergangenheit an als bei globaler Einschätzung. Patienten mit Rückenschmerzen berichteten bei differenzierter Befragung zum aktuellen Schmerz über weniger ausgedehnte Schmerzen als bei globaler Befragung.Schlussfolgerung Die Angaben zur Schmerzausdehnung variieren vor allem bei Patienten mit ausgedehnten Schmerzen in Abhängigkeit von der Differenziertheit der Befragung. In diesen Fällen ist die Wahrscheinlichkeit erhöht, dass sich die Beschwerdesymptomatik zumindest teilweise erst in der Reaktion auf die situativen Befragungsbedingungen konstituiert und daher nicht auf andere Befragungsbedingungen generalisiert werden kann.