Isopropyl alcohol pad use for blood ethanol sampling does not cause false-positive results

This was a retrospective analysis of prospective data collected from a study of blood ethanol levels after the use of the alcohol-based hand sanitizer (ABHS). A total of 5 male volunteers were enrolled. Eight of the 10 total blood ethanol level measurements were drawn after skin preparation with Kendall WEBCOL Alcohol Preps (APP) containing 70% isopropyl alcohol. All had an initial and post-ABHS application blood alcohol level (BAL) drawn, for a total of 10 BAL measurements. Measurements upon completion of the study were <5 mg/dL in all 5 study participants and in each of the 10 blood draws regardless of skin preparation technique. This study demonstrates that the use of isopropyl skin prep pads is unlikely to cause significant false-positive blood ethanol levels.     

The application of multiparameter reference intervals for pre-donation capillary blood counts: the experience of a single institution

Objectives: To evaluate a set of reference counts applied to multiparameter pre‐counts in blood donors. Aim: Analyse the impact of pre‐donation counts and specific reference intervals on donors' management. Background: Multiparameter blood counts allow an improved enrolment process of blood donors due to a prompt identification of abnormalities involving haemoglobin (Hb), white blood cells (WBC) and platelets (PLT). Methods/Materials: Multiple pre‐donation capillary counts were applied in the enrolment process of 13 347 consecutive donors. The rate of specific alterations of permanent exclusion and donor readmittance to donations for temporary exclusion had been evaluated, applying a set of multiparameter reference intervals. Results: Alterations involved Hb in 72·55% of cases, mean corpuscular volume (MCV) in 20·99%, total WBC in 9·39%, lymphocytes in 7·55% and PLT in 6·07%. Among donors with initial alterations (543; 4·06%), 12·70% were readmitted to donations within 15 days, 14·36% had permanent exclusion, 36·83% underwent prompt supplementation treatment and 36·09% were lost at follow‐up or refused treatments. Discussion: The systematic use of blood count reference intervals and pre‐donation multiparameter blood counts allowed prompt identification of WBC, PLT and MCV alterations, readmittance within 15 days of 12·70% of initially excluded donors and contributed to prompt management of supplement deficiency.     

湛江市无偿献血者血液检测结果分析

目的分析无偿献血者血液检测结果,为招募安全献血者提供依据及减少血液报废,确保临床用血安全。方法对湛江市近5年来无偿献血者血液检测情况进行回顾性统计分析。结果丙氨酸氨基转移酶(ALT)不合格率为4.11%,乙型肝炎病毒表面抗原不合格率为0.53%,丙型肝炎病毒抗体不合格率为0.40%,人类免疫缺陷病毒抗体不合格率为0.08%,梅毒抗体不合格率为0.65%;总检测不合格率为5.57%。结论 ALT阳性是血液报废的最主要因素,梅毒抗体的阳性率逐年增高,成为仅次于ALT阳性而造成血液报废的重要因素。     

A rapid ABO and RhD test demonstrates high fidelity to blood bank testing for RhD typing

Background

The rapid provision of blood products is life-saving for patients with massive hemorrhage. Ideally, RhD-negative blood products would be supplied to a woman of childbearing potential whose Rh type is unknown due to the risk of D-alloimmunization and the potential for hemolytic disease of the fetus and newborn to occur if RhD-positive blood products are transfused. Therefore, there is a need for a test that rapidly determines her RhD type. This study compared the RhD type determined using a rapid ABO and RhD test to the RhD type determined by an immunohematology reference laboratory.

Methods

After receiving ethics review board approval, 200 random, unique, deidentified patient samples that had undergone routine pretransfusion testing in an immunohematology reference laboratory using column agglutination technology were collected and tested using a rapid ABO and RhD test (Eldoncard Home kit 2511). The RhD typing results from these two methods were compared to determine the accuracy of the rapid ABO and RhD test.

Results

The rapid ABO and RhD test produced results that were concordant with the transfusion service's results in 199/200 (99.5%) of cases, with a negative predictive value of 98.2% and 99.3% sensitivity. The single outlier was likely an RhD variant due to its serological characteristics.

Discussion

These data indicate that this rapid ABO and RhD test could be used for the rapid determination of a patient's RhD type, perhaps even in the emergency department, which could guide the selection of blood products provided during their resuscitation.     

Feasibility and cost-benefit of implementing pooled screening for HCVAg in small blood bank settings

To examine the accuracy, feasibility and benefits of screening for hepatitis C virus core antigen (HCVAg) using enzyme-linked immunosorbent assay (ELISA) test in pools. Many countries cannot afford to test blood donations for hepatitis C using molecular methods. Screening individual units using the ELISA HCVAg test is an acceptable, yet still expensive, alternative, especially for small blood bank settings. This study evaluated the option of screening for HCVAg in pools. The sensitivity (Se) and specificity (Sp) of HCVAg in pools of three and six antibody-negative samples were estimated and compared with polymerase chain reaction (PCR). The feasibility and cost-benefit of the assay was assessed on 960 routine samples collected at a hospital blood bank in Gaza. Based on results for 50 PCR-positive pools and 50 and 110 PCR-negative pools of three and six, the Se of testing in pools of three and six samples is 80-82% [95% confidence interval (CI): 66.3-91.4] and Sp >or=98% (95% CI: 89.4-100.0) compared with PCR. The incidence of antigen in donors in Gaza was 0.1% (95% CI: 0-0.56). Cost analyses suggested significant benefits from implementing screening blood donations for HCVAg when the incidence rate is >4.2/10,000, leading to reduction in the expenditures needed to treat patients infected with HCV. The risk of transfusion-transmitted hepatitis C in resource-deprived developing countries can be efficiently reduced by additional screening of antibody-negative blood donations for HCVAg in pools of six.     

The Saliva Strip Test Is an Accurate Method to Determine Blood Alcohol Concentration in Trauma Patients

OBJECTIVES: To determine the accuracy of alcohol saliva testing (AST) in trauma patients. METHODS: Blood alcohol concentration (BAC) was measured by using both AST (QED A350; STC Technologies, Bethlehem, PA) and blood serum levels in 100 trauma patients admitted to the emergency department of an urban Level 1 trauma center. RESULTS: All 41 patients who tested positive for BAC on AST (mean [+/-SD]: 167.9 +/- 16.16; range: 20-350 mg/dL) also tested positive on serum determination (mean: 197.6 +/- 13.79; range: 22-446 mg/dL). Correlation between the two positive tests was significant (0.879, p < 0.001). Of the remaining 61 patients, 59 tested negative on both tests, while two patients with BACs of <30 mg/dL tested negative on the AST. For 18 patients with blood in the oropharynx, there was a correlation of 0.976 (p < 0.001, two-tailed) between serum and AST tests. CONCLUSIONS: The AST method of measuring BAC in trauma patients is accurate. Blood in the oral cavity did not appear to affect the accuracy of the test.     

广州番禺地区开展核酸血液筛查的应用情况

目的分析广州番禺地区开展核酸血液筛查以来情况,探讨核酸检测技术(NAT)在血液筛查中的应用价值。方法采用罗氏诊断Cobas S201系统对两遍酶免4项(ELISA)及ALT筛查阴性的献血者标本进行HIV-RNA、HCV-RNA和HBV-DNA 3项联合、6样本混样检测,对混样阳性的样本进行拆分实验,并对拆分阳性的标本进行分项确证实验,对确证实验HBV-DNA阳性的样本进行乙肝两对半血清学标志物的酶免检测。结果共完成40 107例标本的核酸混样检测,拆分阳性的标本60例,阳性率为0.150%(60/40 107)。对这60例样本做分项鉴别实验,结果HBV-DNA阳性47例,阳性率为0.117%(47/40 107),其余13例确认阴性。对47例分项鉴别实验HBV-DNA阳性的样的进行乙肝两对半血清学标志物检测,结果显示:单独HBc Ab阳性15例(31.9%),HBc Ab阳性伴HBs Ab弱阳性15例(31.9%)(其中有2例HBs Ab较强阳性S/CO分别达到14.6、22.3),HBe Ab、HBc Ab阳性8例(17.0%),单独HBs Ab阳性4例(8.5%),两对半全部阴性4例(8.5%),HBs Ab、HBe Ab、HBc Ab 3项阳性的1例(2.1%)。结论血站酶免4项及ALT筛查阴性的血液仍然存在一定的输血传染残余风险,HBs Ag阴性HBV-DNA阳性样本的两对半抗体阳性组合模式有6种,以单独HBc Ab阳性和HBc Ab阳性伴HBs Ab弱阳性占比最大。应用ELISA联合NAT进行血站血液筛查能更有效保障血液安全。     

直接药敏试验与常规药敏试验在血培养中的应用比较

目的评价直接药敏试验和常规药敏试验在血液细菌感染中的临床应用意义。方法随机选取2012年3月至2014年5月广州中医药大学附属新会中医院280份血培养阳性标本,对上述280份标本分别予以直接药物敏感试验和常规药敏试验,研究2种检测结果的细菌鉴定结果以及药敏结果在2种不同方法中的相关性。结果直接细菌鉴定法与常规细菌鉴定法的一致性为92.5%,2种检测方式的敏感度、药物耐药及中度敏感的符合率比较,差异无统计学意义(P0.05)。结论直接药敏试验可以缩短血培养阳性标本的报告时间,有效指导临床合理选用抗菌药物。     

自制输血相容性检测室内质控品保存条件的研究

本研究目的是利用输血相容性检测实验室现有血液标本资源,建立自制室内质控品技术。随机选取24名A型RhD阳性的健康献血者,分别采集静脉血4ml,采用析因设计方法,根据使用抗凝剂种类、是否添加红细胞保存液以及标本每日室温存放时间,将24个标本随机平均分成8组,将所有盛装标本的试管盖帽后4℃保存,每天在室温放置1小时或2小时。分别在保存的0、7、14、21、28、35天测定所有标本的ABO、RhD血型（记录正反定型的凝集强度）、IgM抗B抗体效价和上清液中游离血红蛋白浓度并计算其增量值。结果表明：使用ACD-B抗凝剂并添加MAP红细胞保存液,每天室温放置1小时（A282C1）组标本的红细胞损伤最小,各时间点FHb浓度及其增量值均最低（P〈0．01）,35天时FHb浓度仅为（245．1±84,5）mg／L。保存过程中A抗原、D抗原及kM抗B抗体反应活性无明显变化（P〉0．05）。结论：在输血相容性检测实验室现有条件下,可以利用本研究建立的A282C1方案制备出性能相对稳定、可有效保存的能够满足室内质控要求的改良全血室内质控品。     

成都市无偿献血者血液检测结果与人群结构分析

目的了解成都市无偿献血人群结构,为制定招募安全血源的策略提供依据。方法收集2004年11月~2005年6月的献血者资料(性别、年龄、文化程度、职业等)及其血液HBsAg、抗-HCV、抗-HIV、梅毒抗体检测结果,运用统计学方法分析二者的关系。结果①45270名献血者血液检测阳检率(3.11%)随着年龄增长、文化程度的降低而增加,与献血者的职业相关;②献血者中为18~30岁的年轻人占76.7%,随着年龄增加,参与献血的女性明显少于男性;③高中以上文化程度的献血者占81.6%,其阳检率远低于初中和小学文化程度的献血者;④献血者中农民阳检率最高(6.63%),其次为工人和商业服务业人员,医生和学生;⑤献血者中性别、年龄、职业和文化程度不明(记录不完整)的“未知”组血液阳检率远高于资料完整的献血者。结论献血者选择过程的质量控制是招募安全血源策略中的重要环节;年轻人、高文化程度者和学生是较安全的献血者,应针对初中以下文化程度的献血者和农民开展无偿献血、献血者传染病防治知识的健康教育并进行效果评价。     

Comparison and validation of point of care lactate meters as a replacement for fetal pH measurement

Objective

To validate a point of care lactate device to replace fetal pH measurement.

Study design and methods

Cord blood samples drawn immediately following delivery were tested on the Nova Lactate Plus and ARKRAY Lactate Pro, the Corometrics 220 pH System, and the Vitros chemistry analyzer (used as lactate reference).

Results

Nova demonstrated a constant positive bias relative to the lactate reference method; while the Lactate Pro correlated well with the reference method up to 6 mmol/L. Receiver operating characteristic (ROC) curve analysis showed optimal sensitivity and specificity for predicting pH < 7.20 at lactate values of 6.8 mmol/L for the Nova and 4.8 mmol/L for the Lactate Pro.

Conclusion

Using Lactate Pro the best cut-off for predicting pH ≤ 7.20 was 4.8 mM; which coincides with current clinical cut-offs. Thus any lactate device that correlates well with the laboratory reference method can be used with a clinical cut-off of 4.8 mmol/L.     

2种血糖仪检测方法与生化仪血糖检测的比对

目的对2种血糖仪检测方法与生化仪血糖检测进行比对,对结果、临床可操作性及影响因素进行评估。方法选取糖尿病和非糖尿病患者共61例,早晨抽取空腹静脉血2mL置于含有EDTA-K2的抗凝管中颠倒混匀。取1滴静脉血用血糖仪测静脉全血血糖(VBG),剩余标本离心取血浆用生化仪(日立7600)检测静脉血浆葡萄糖浓度(VPG)。抽取静脉血后5min内用同一血糖仪检测指尖毛细血管血糖(CBG)。以VPG为参考标准,分别计算血糖仪VBG和CBG的偏差;用统计软件分别进行VBG或CBG与VPG的相关性分析;针对VBG和CBG绘制Parkes误差网格图,判断数据的临床接受程度。结果使用罗氏公司的Accu-Chek Performa血糖仪检测静脉血糖或毛细血管血糖与生化方法血糖比对,结果呈线性相关(r分别为0.991和0.989),偏差范围均能达到国家标准,所有数据在临床可接受区。结论便携式血糖仪检测静脉血糖与生化血糖结果比对,因标本来源一致、操作流程简单、可人为制造过高或过低血糖样本,故建议医疗机构采用该方案进行定期比对实验。     

Reference values for blood pressure response to cycle ergometry in the first two decades of life: comparison with patients with a repaired coarctation of the aorta

Background: Hemodynamic responses to exercise are used as markers of diagnosis for cardiac diseases, systolic blood pressure (SBP) especially. However, the reference values for SBP in children at peak exertion level are outdated. This study aimed to establish current reference values for SBP, rate pressure product (RPP), and circulatory power (CircP).

Methods: Data from children who previously underwent cardiopulmonary exercise testing were categorized as healthy (N = 184; age 12.6 ± 2.9 years), and CoA patients (N = 25; age 13.0 ± 3.2 years). With the Lambda-Mu-Sigma (LMS) method, percentile curves were made for SBP, CircP, and RPP in function of peak work rate (Wpeak). Data of CoA patients were used to validate the reference values.

Results: Wpeak was the best predictor of peak SBP during exercise. The prediction equations for SBP, CircP and RPP were: (0.2853 x Wpeak) + 111.46; (10.56 x Wpeak) + 2550.2 and (61.879 x Wpeak) + 19.887, respectively. CoA patients showed significantly increased values for peak SBP (Z-score 1.063 ± 1.347).

Conclusion: This study provides reference values for SBP, RPP, and CircP at peak exercise. These values can be used for objective evaluation of participants 6–18 years of age in a Dutch population.