Blood Transfusion or Blood Substitution?

Blood transfusion has become a universally accepted, life-saving procedure in modern clinical medicine. In addition, specific blood fractions are widely used in the therapeutic treatment of haematological disorders. Problems are, however, encountered in conventional transfusion practice and in the clinical use of blood components. This paper outlines some of those problems and considers how plasma expanders and oxygen-carrying blood substitutes may be used to overcome some of them. The extent to which acceptable blood substitutes have been developed and tested in both animal and human studies is especially emphasized.     

Blood

 【网址】http://bloodjournal.hematologylibrary.org/【类型】专业期刊《血液》(Blood),由美国血液学会（American Society of Hematology）主办,周刊,由William Dameshek于1946年创刊。该刊是血液学领域中被引次数最高的期刊之一,它为全球血液科临床人员以及相关研究人员提供了一个国际型学术平台。该刊涵盖了血液学的各个方面,包括白细胞疾病（良性和恶性）、红细胞、血小板、止血机制、血管生物学、免疫学、血液学和肿瘤学等。所有论文均经过严格的同行评议,并根据文章的原创性、准确性和表达清晰性进行严格筛选,尤其注重各方面的原始研究。现今《血液》已被Index Medicus、Excerpta Medica、Current Contents、SCI、SCISEARCH、 Automatic Subject Citation Alert、 ISI/BIOMED、BIOSIS等数据库收录。据2012版期刊引证报告（JCR）显示,影响因子为9.060。目前,该刊可通过期刊官方网站、Cite Track和Medline于论文正式印刷发表前提前访问。该刊所有论文可于出版12个月后免费阅读。 (中国医科大学医学信息学系 隋明爽 黄亚明 整理)     

Alternatives to Human Blood and Blood Resources

Biotechnology is increasingly providing alternatives to established transfusion products, with the promise of freedom from infectivity and unlimited supply. Such products must demonstrate a safety and efficacy at least as great as current products, and thereafter an improved cost-benefit ratio. Alternatives to established products may be categorised as:

• ? Alternatives made from blood donations.
• ? Substitutes (acting by distinct mechanisms).
• ? Recombinant analogs.
• ? Cellular therapies (including gene therapy).

This overview covers the current status in each of these categories, and likely trends in the near future. Recombinant therapeutic proteins are already established in certain indications, and are likely to be extended to a wider range of applications as the methods for bulk production are improved. Alternative products from donated blood should find niche indications, especially for acute therapy, but cellular therapy is unlikely to be widely implemented on this timescale, except as an adjunct in life-threatening indications. Substitutes are perhaps the most interesting category and are expected to have a major impact, particularly through the use of “poietins” to stimulate endogenous production of circulating cell populations.     

献血后穿刺部位局部淤血400例的预防

目的讨论献血后对穿刺部位进行合理护理对减少不良反应发生率影响。方法对400例献血者选择合适的采血静脉,使用三指按压法,注意采后止血措施。结果只有12例发生局部不良反应,占总人数的3%,无1例引起献血者投诉。结论完善采血技术可改善不良反应的发生率,减少献血者投诉。     

Blood Kallikrein

Three chief components of the kallikrein-kinin system (kallikrein, kininogen, kininase) were studied in the blood of 42 patients with acute pancreatitis. Significant increase in content of kallikrein, decrease in level of kininogen, and increase of kininase activity were observed. The highest values for kallikrein, kininogen and kininase activity were found in patients in whom acute pancreatitis was accompanied by hemodynamic changes.     

Blood banks

Viral hepatitis is still one of the most common and severe complications of blood transfusions, with a high mortality rate. The incidence of viral hepatitis after blood transfusions has gone down, but it hasn't disappeared. In Mexico, the estimated risk of infection with HCV is 1 for every 103,000 units administered. The routes of transmission include infected whole blood (IgG), anti-D immunoglobulin and factor VIII. Mexico now has official regulations for blood transfusion. These laws gave place to a reduction of near 57% in the prevalence of infection among donors. The national prevalence of HCV in 2001 was estimated at 0.01 percent. Several tests, like PCR and core HCV antigen detection to determine AcHC, are being applied to guarantee the safety of national blood products.     

Adenine-Supplemented Blood

IgG in factor VIII preparations was studied as a possible cause of adverse reactions following infusion of hemophiliacs. Thin-layer immuno-gel filtration analysis of nine products from seven firms demonstrated aggregated and monomeric IgG at highly variable amounts and proportions. These factor VIII products contained from 20 to 700 mg IgG per 1000 IU of factor VIII; IgG-fibrinogen complexes were demonstrated by double-antibody testing. A relationship is suggested between aggregated IgG and/or IgG complexes in factor VIII concentrates and adverse clinical reactions. They may also partially explain abnormalities and aberrations of the immune system previously reported in hemophiliacs.     

Blood cultures

We reviewed the literature on the performance of the blood culture as a diagnostic test and analyzed the data with Bayes' theorem to find the optimal number of cultures to draw. The blood culture is unusually dependent on physician behavior (use of sterile technique, the number and timing of cultures, volume of blood drawn) and on their clinical judgment (estimating the pretest probability of bacteremia, anticipating the causative pathogen, interpreting the results). Because there is no independent "gold-standard" procedure against which to evaluate this test, sensitivity and specificity can only be approximated. Sensitivity can be maximized by doing multiple cultures containing at least 10 mL of blood per set. Specificity can be maximized by adhering strictly to aseptic techniques and by requiring that multiple sets be positive for the series to be considered positive when the anticipated pathogens are also common contaminants. Two or three blood culture sets almost always suffice to establish or rule out bacteremia, although on some occasions obtaining more than three sets of cultures is indicated. One set is rarely, if ever, sufficient.     

Blood substitutes

Blood substitutes are solutions intended to replace transfusion of banked red blood cells. Several variations of products based on either hemoglobin (animal or human) or perfluorocarbon emulsions are in advanced stages of clinical development. The need for such products is pressing as shortages of banked blood worsen and awareness of the dangers of blood transfusion increases. Animal and human studies with these cell-free oxygen carriers have led to new concepts of how oxygen is delivered to tissue and how the microcirculation is regulated. Although development of products is exciting and timely, understanding how they function to perfuse and oxygenate tissue could be at least as important. Because cell-free oxygen carriers will perfuse every organ of the body, their effects are far-reaching, and the transition from the laboratory to the bedside can be expected to be slow and deliberate. Comparison of oxygen carriers with more traditional starch-based products provides new insight into the interaction of oxygen transport, microvascular perfusion, and blood volume expansion.