缺血性脑血管病急性期REG改变及其与伴随高血压的关系

本文应用ＲＥＧ（脑阻抗血流图）法、检测缺血性脑血管病发病急性期伴随、不伴随高血压的脑血管功能变化，结果显示；伴随高血压未病侧脑血流量指标较健康对照组有显著下降，各缺血性血管病的弹性指标病侧、未病侧较健康对照组有不同程度下降，表明脑血管病后伴有高血压的脑血管功能减退更为显著。上述结果与临床表现相一致、故用ＲＥＧ０这一简单、重复性较好的方法检测脑血管功能、特别是病后伴随高血压的检测，对指导预防再复发是有一定意义的。     

脑阻抗血流图波幅变化与缺血性脑血管病患者预后的关系

为了观察脑血管病患者发病后脑阻抗血流图波幅高低变化与预后的关系。作者对济南市历下区人民医院和山东中医药大学附属医院住院的缺血性脑血管病患者149例进行了预后的随访调查,现总结如下:     

心肺阻抗血流图对胸闷病人的诊断价值

目的：了解心肺阻抗血流图对胸闷病人的诊断价值。材料与方法：分析了101例以胸闷为唯一主述并以心电图及胸片检查均为阴性的病人的心肺阻抗血流图，并与60例正常人的心肺阻抗血流图相比较，结果：有胸闷者的心肺阻抗血流图的异常率明显高于正常组，尤以甲亢，甲减，右心射血功能减退，肺动脉高压，左心射血功能减退表现居多，其中部分经治疗后临床症状和心肺阻抗血流图的变化以及其他有关检查均明显好转，结论：作为一种无创检查，心肺阻抗血流图对胸闷病人的早期诊断及对疾病的发展及治疗效果的判断也提供着一定的指导作用。     

子宫肌瘤患者手术前后盆腔阻抗血流图对比分析

目的探讨现有的盆腔阻抗技术其电力线能否由人体皮表通过深部组织脏器并反映所测区域的血液循环状态．方法选择经Ｂ超检查与手术证实的子宫肌瘤患者３５例，采用盆腔阻抗法，于术前、术后１０天及术后９０天分别检测３次盆腔血流图．统计学分析采用组间均数ｔ检验．结果子宫肌瘤患者的盆腔血流图中Ｈｓ（盆腔血流灌注波幅）、Ｃｄｚ／ｄｔｍａｘ（盆腔血流灌注速度）、Ｃ／Ｂ－ Ｃ（盆腔血流灌注指数）均降低，与对照组相比有显著差异（ｐ＜０．０１）；与术后１０天复查组相比无差异（ｐ＞ ０．０５）；与术后 ９０天复查组 １７例相比有显著差异（ｐ＜０．０１）对照组与术后９０天复查组 １７例相比无差异（ｐ＞０．０５）．结论盆腔阻抗技术完全可以客观、真实、无创性地综合反映盆腔的血流动力学变化，证实现用的阻抗技术电力线完全可以经人体表层通过内脏器官直接提取其生物阻抗信息．     

心阻抗微分环及其临床意义

在心血流图原理的基础上，将阻抗血流图及其微分图同时输入到示波器X及Y轴上，获得了阻抗微分环（IDL），经临床与动物实验证实，各种影响心脏舒缩功能的诸因素均对IDL有明显的影响。IDL克服了单一指标的局限性，对判断心脏舒缩功能及病理改变提供了一些有意义的指标，对具有较好的灵敏性，是一种新的无创伤心功能检查方法。     

心阻抗血流图心搏量计算公式的问题

心阻抗血流图目前已在我国广泛应用，并不断取得进展。使用心搏量公式的计算结果评价心功能，是心阻抗血流图的重要应用方向之一。本文从作为Ｋｕｂｉｃｅｋ心搏量公式理论基础的并联阻抗模型和Ｎｙｂｏｅｒ公式开始，对Ｋｕｂｉｃｅｋ公式进行了讨论。并提出了在临床应用现状的条件下，应特别注意影响心搏量计算结果的两个问题：基础阻抗值Ｚ０的影响和血液电阻率ρ不变。     

采用心阻抗血流图对体外反搏的控制研究

本文采用点状电极技术，自适应信号处理技术，微型计算机检测控制技术，对反映每一心动周期中，胸腔内主动脉等大血管及心脏血液搏动性变化的心阻抗血流图进行检测和处理。由临床实验采用五个点状电极获得心电信号，心阻抗血流信号和自适应处理阻抗参考信号。自适应处理采用变步长ＬＭＳ噪声抵消算法，消除阻抗血流图波形中反搏引起身体震动的干扰，获得波形稳定、特征点明显的心阻抗血流图波形，从而探索利用心阻抗血流图波形对反搏充排气的控制。     

低能量He-Ne激光血管内照射与急性脑血管病微循环、血液流变学研究

通过对60例急性脑血管病患者使用低能量He－Ne激光血管内照射治疗，发现其甲襞微循环治疗前后有明显改变。即治疗后管襻数增多管襻畸形减少，血流速度增快。其血液流变学改变表现为治疗前全血病切变率粘度为5．91±1．68，治疗后降为4．88±1．04，P＜0．001。说明红细胞变形能力显著提高，红细胞聚集性显著降低。故低能量He－Ne激光血管内照射这一方法对治疗急性脑血管病有一定的临床意义。     

长春西丁治疗脑血管病60例微循环疗效分析

本文对60例缺血性脑血管病人口服长春西丁片前后甲襞微循环指标变化进行了研究。结果显示缺血性脑血管病患者均有不同程度微循环障碍。服用长春西丁片后微循环明显改善,解除红细胞聚集、增快血流速度、扩张微血管口径、增加毛细血管开放数。总积分值降低,有统计学意义。本研究显示了长春西丁在脑血管病微循环方面的治疗作用,并讨论了作用机理。     

心阻抗血流图电阻新公式与常用电阻公式的比较分析

本文是我们建立一种心阻抗血流图新理论的系列研究之三。本文根据文献［１，２］所得出心阻抗血流图新理论和电阻公式，通过数值计算，给出了电阻新公式与常用电阻公式的差别，分析了产生差别的原因；并对阻抗血流图中的电阻公式和我们提出的新公式进行了比较。     

Sources and outcome of bloodstream infections in cancer patients: the role of central venous catheters

Simultaneously drawn quantitative blood cultures are used to diagnose catheter-related bloodstream infections. We conducted this study to determine the frequency with which central venous catheters were the source of bloodstream infections detected through paired positive blood cultures drawn from cancer patients and the potential for quantitative blood cultures to help predict outcome in neutropenic and non-neutropenic patients. From September 1999 to November 2000, we identified 169 patients with bloodstream infections. Of all bloodstream infections, 56% were catheter-related bloodstream infections. Gram-positive bacteremia was found to be catheter-related in 55% and 69% of patients with hematologic malignancy and solid tumors, respectively, whereas gram-negative bacteremia was catheter-related in only 19% of patients with underlying hematologic malignancy and in 60% of patients with solid tumor (P = 0.01). By multivariate analysis, poor response was associated with critical illness and persistent neutropenia (P < 0.01). In neutropenic patients with catheter-related bloodstream infections, peripheral quantitative blood cultures of ≥100 CFU/mL was also associated with poor response (P = 0.05). Central venous catheters were the major source of bloodstream infection, particularly in patients with solid tumors. In addition to critical illness and persistent neutropenia, quantitative blood cultures might be useful in predicting outcomes for neutropenic patients with catheter-related bloodstream infections.     

The Value of Combining Blood Culture and SeptiFast Data for Predicting Complicated Bloodstream Infections Caused by Gram-Positive Bacteria or Candida Species

Management of complicated bloodstream infections requires more aggressive treatment than uncomplicated bloodstream infections. We assessed the value of follow-up blood culture in bloodstream infections caused by Staphylococcus aureus, Enterococcus spp., Streptococcus spp., and Candida spp. and studied the value of persistence of DNA in blood (using SeptiFast) for predicting complicated bloodstream infections. Patients with bloodstream infections caused by these microorganisms were enrolled prospectively. After the first positive blood culture, samples were obtained every third day to perform blood culture and SeptiFast analyses simultaneously. Patients were followed to detect complicated bloodstream infection. The study sample comprised 119 patients. One-third of the patients developed complicated bloodstream infections. The values of persistently positive tests to predict complicated bloodstream infections were as follows: SeptiFast positive samples (sensitivity, 56%; specificity, 79.5%; positive predictive value, 54%; negative predictive value, 80.5%; accuracy, 72.3%) and positive blood cultures (sensitivity, 30.5%; specificity, 92.8%; positive predictive value, 64%; negative predictive value, 75.5%; accuracy, 73.9%). Multivariate analysis showed that patients with a positive SeptiFast result between days 3 and 7 had an almost 8-fold-higher risk of developing a complicated bloodstream infection. In S. aureus, the combination of both techniques to exclude endovascular complications was significantly better than the use of blood culture alone. We obtained a score with variables selected by the multivariate model. With a cutoff of 7, the negative predictive value for complicated bloodstream infection was 96.6%. Patients with a positive SeptiFast result between days 3 and 7 after a positive blood culture have an almost 8-fold-higher risk of developing complicated bloodstream infections. A score combining clinical data with the SeptiFast result may improve the exclusion of complicated bloodstream infections.     

中性粒细胞/淋巴细胞比值对血流感染的诊断价值

目的探讨5项感染标志物对血流感染的诊断价值。方法随机选取望京医院血培养阳性的血流感染患者110例为研究组,血培养阴性的细菌感染患者30例为对照组。在血培养的同1天抽取静脉血,检测全血细胞计数和C反应蛋白(CRP)。比较两组白细胞(WBC)、中性粒细胞(NEU)、淋巴细胞(LYM)、中性粒细胞/淋巴细胞比值(NLCR)和CRP的差异。结果血流感染组WBC、NEU、NLCR、CRP均显著高于对照组(P0.05),而LYM显著低于对照组(P0.05)。5项感染标志物中,NLCR和LYM诊断血流感染的受试者工作特征曲线下面积(ROC-AUC)分别为0.808和0.756。当NLCR取临界值为9.33时,敏感性为63.6%,特异性为93.3%;LYM小于等于0.97为临界值时,敏感性为58.2%,特异性为86.7%。进一步,在血培养阳性患者中,革兰氏阴性菌所致的血流感染组的NLCR高于革兰氏阳性菌血流感染组,NLCR在区分血流感染的类型中具有重要的临床意义。结论 NLCR优于其他常规感染指标,有助于血流感染的诊断。     

DNA fingerprinting analysis of coagulase negative staphylococci implicated in catheter related bloodstream infections

AIMS: The epidemiological assessment of cases of coagulase negative staphylococcal catheter related bloodstream infection. METHODS: Two hundred and thirty patients with suspected catheter related bloodstream infection were evaluated over a two year period. Central venous catheters were cultured both endoluminally and extraluminally. Peripheral blood, catheter hubs, skin entry, and skin control sites were also cultured. Pulsed field gel electrophoresis (PFGE) was used to DNA fingerprint coagulase negative staphylococci isolated from patients with presumptive catheter related bloodstream infection. RESULTS: Sixty cases of catheter related bloodstream infection were identified, 21 of which were attributed to coagulase negative staphylococci. Two hundred and ninety four separate isolates of coagulase negative staphylococci from the 21 cases of catheter related bloodstream infection were subjected to PFGE (mean of 14 for each case). Catheter related bloodstream infection was only confirmed by PFGE analysis in 16 of the 21 cases because in the remaining five cases peripheral blood and central venous catheter coagulase negative staphylococci isolates were different. Skin entry, control skin, and central venous catheter hub isolates matched peripheral blood isolates in six, four, and seven cases, respectively. Coagulase negative staphylococci isolates could not be cultured from the patients' own skin in seven cases of catheter related bloodstream infection. Central venous catheter lumens were colonised in all cases of catheter related bloodstream infection compared with 44-81% of cases that had positive external surface catheter tip cultures, depending on the threshold used to define significant growth. CONCLUSIONS: Catheter related bloodstream infection as a result of coagulase negative staphylococci may be over stated in about a quarter of cases, unless a discriminatory technique is used to fingerprint isolates. No single, simplistic route of bacterial contamination of central venous catheters was identified, but endoluminal catheter colonisation is invariably present in cases of catheter related bloodstream infection.     

Risk factors for central venous catheter-related infections in general surgery.

BACKGROUND AND PURPOSE: Central venous catheter (CVC) infection is a common problem during hospitalization and nosocomial bloodstream infection in these patients is associated with increased morbidity, mortality, and health care cost. This prospective study examined the risk factors of CVC-related infections. METHODS: During a 6-month period, a total of 281 patients who underwent central venous catheterization after general surgery were enrolled. RESULTS: The mean duration from CVC insertion to the development of infection was 7.12 days. The rate of bloodstream infection without isolation of the same organism from the catheter was 1.4% (4/281). The rate of catheter-related bloodstream infection was 6.0% (17/281). The rate of catheter bacteremia, defined as positive culture from a catheter blood sample in a patient without signs of infection, was 8.5% (24/281). The incidence of catheter-related bloodstream infection was 7.5/1000 catheter-days. Risk factors for catheter-related infection on univariate analysis included place of insertion (operating room or surgical ward), total parenteral nutrition (TPN), more than 3 tubings, and duration of catheterization. TPN was a significant risk factor in the logistic regression analysis. CONCLUSIONS: Established infection control guidelines should be rigorously observed with regard to catheter use and various risk factors controlled to prevent the occurrence of CVC-related infection, especially in patients receiving TPN.     

Enhanced Diagnostic Yields of Bacteremia and Candidemia in Blood Specimens by PCR-Electrospray Ionization Mass Spectrometry

A prospective study was performed to determine the value of direct molecular testing of whole blood for detecting the presence of culturable and unculturable bacteria and yeasts in patients with suspected bloodstream infections. A total of 464 adult and pediatric patients with positive blood cultures matched with 442 patients with negative blood cultures collected during the same period were recruited during a 10-month study. PCR amplification coupled with electrospray ionization mass spectrometry (PCR-ESI-MS) plus blood culture reached an overall agreement of 78.6% in the detection and species-level identification of bacterial and candidal pathogens. Of 33 culture-negative/PCR-ESI-MS-positive specimens, 31 (93.9%) were judged to be truly bacteremic and/or candidemic based on a medical chart review and analytical metrics. Among the 15 culture-positive specimens in which PCR-ESI-MS detected additional bacterial or yeast species, 66.7% and 20.0% of the additional positive specimens by PCR-ESI-MS were judged to be truly or possibly bacteremic and/or candidemic, respectively. Direct analysis of blood samples by PCR-ESI-MS rapidly detects bacterial and yeast pathogens in patients with bloodstream infections. When used in conjunction with blood culture, PCR-ESI-MS enhances the diagnostics of septicemia by shortening test turnaround time and improving yields.     

Classification of positive blood cultures: computer algorithms versus physicians' assessment - development of tools for surveillance of bloodstream infection prognosis using population-based laboratory databases

ABSTRACT: BACKGROUND: Information from blood cultures is utilized for infection control, public health surveillance, and clinical outcome research. This information can be enriched by physicians assessments of positive blood cultures, which are, however, often available from selected patient groups or pathogens only. The aim of this work was to determine whether patients with positive blood cultures can be classified effectively for outcome research in epidemiological studies by the use of administrative data and computer algorithms, taking physicians assessments as reference. METHODS: Physicians assessments of positive blood cultures were routinely recorded at two Danish hospitals from 2006 through 2008. The physicians assessments classified positive blood cultures as: a) contamination or bloodstream infection; b) bloodstream infection as mono- or polymicrobial; c) bloodstream infection as community- or hospital-onset; d) communityonset bloodstream infection as healthcare-associated or not. We applied the computer algorithms to data from laboratory databases and the Danish National Patient Registry to classify the same groups and compared these with the physicians assessments as reference episodes. For each classification, we tabulated episodes derived by the physicians assessment and the computer algorithm and compared 30-day mortality between concordant and discrepant groups with adjustment for age, gender, and comorbidity. RESULTS: Physicians derived 9,482 reference episodes from 21,705 positive blood cultures. The agreement between computer algorithms and physicians assessments was high for contamination vs. bloodstream infection (8,966/9,482 reference episodes [96.6%], Kappa = 0.83) and mono- vs. polymicrobial bloodstream infection (6,932/7,288 reference episodes [95.2%], Kappa = 0.76), but lower for community- vs. hospital-onset bloodstream infection (6,056/7,288 reference episodes [83.1%], Kappa = 0.57) and healthcare-association (3,032/4,740 reference episodes [64.0%], Kappa = 0.15). The 30-day mortality in the discrepant groups differed from the concordant groups as regards community- vs. hospitalonset, whereas there were no material differences within the other comparison groups. CONCLUSIONS: Using data from health administrative registries, we found high agreement between the computer algorithms and the physicians assessments as regards contamination vs. bloodstream infection and monomicrobial vs. polymicrobial bloodstream infection, whereas there was only moderate agreement between the computer algorithms and the physicians assessments concerning the place of onset. These results provide new information on the utility of computer algorithms derived from health administrative registries.     

Salmonella bloodstream infection in Ghanaian children

Objective: To examine the frequency of community-acquired salmonella bloodstream infection in Ghanaian children and the occurrence of antibiotic resistance in salmonellae.
Methods: The study comprised 472 patients with a blood culture obtained within 48 h of admission to the pediatric department of Korle Bu Teaching Hospital in Accra, Ghana, over a 3-month period. All Salmonella isolates from blood cultures were speciated and antibiotic susceptibility tests were performed. Clinical data of children with salmonella bloodstream infection were compared to those of controls. Two control groups were identified: all children enrolled in the study without salmonella bloodstream infection (group 1), and those with bloodstream infection due to other organisms (group 2).
Results: A pathogen was isolated from 111 children (23.5%), and salmonellae were among the most common isolates ( n =24; 21.6%). Among Salmonella strains, S. enteritidis ( n =14;59%) predominated over S. typhi ( n =6;25%). Resistance to several antibiotics was only found in S. enteritidis isolates ( n =8;57%). Children with salmonella bloodstream infection presented more often than controls with severe anemia, jaundice, abdominal pain and distension as well as hepatomegaly and splenomegaly. They were also hospitalized for a significantly longer period, but the case-fatality rate was similar.
Conclusions: Salmonella bloodstream infection, especially due to non-typhoidal strains, is a potential health problem for Ghanaian children and may be complicated by resistance to the commonly available antibiotics.     

Corynebacterium striatum bacteremia associated with central venous catheter infection

Corynebacterium striatum (C striatum) has been considered a contaminant of blood culture in past decades. Here we report the case of a patient with acute deterioration of chronic renal failure. She received hemodialysis and died from C striatum bacteremia. By using a randomly amplified polymorphic DNA (RAPD) method, we found that an association existed between C striatum from the bloodstream and that from the central venous catheter. We suggest that C striatum could be a pathogen of bloodstream infection in patients with such a catheter in place.     

Colonization, bloodstream infection, and mortality caused by vancomycin-resistant enterococcus early after allogeneic hematopoietic stem cell transplant.

Bloodstream infection caused by vancomycin-resistant enterococcus (VRE) is associated with very high mortality among allogeneic hematopoietic stem cell transplant (alloHSCT) recipients. However, it remains unclear whether VRE bloodstream infection directly causes mortality in the early posttransplant period or is simply a marker of poor outcome. To determine the risk factors for VRE bloodstream infection and its effect on outcome, we followed 92 patients screened for stool colonization by VRE upon admission for alloHSCT. Patient records were reviewed to determine outcomes, including mortality and microbiologic failure. Colonization by VRE was extremely common, occurring in 40.2% of patients. VRE bloodstream infection developed in 34.2% of colonized patients by day +35, compared to 1.8% without VRE colonization (P < .01). VRE bloodstream infection was associated with a significant decrement in survival and frequent microbiologic failure, despite treatment with linezolid and/or daptomycin. Five (35.7%) of 14 patients with VRE bloodstream infection had attributable mortality or contributing mortality from the infection. Strain typing by pulsed-field gel electrophoresis identified 9 different VRE strains among the 37 colonized patients and 5 patients with different strains recovered from the stool and the blood. In conclusion, stool screening effectively identified patients at extremely high risk for VRE bloodstream infection. The high mortality of VRE in the early posttransplant period supports the use of empiric antibiotics with activity against VRE during periods of fever and neutropenia in colonized patients.