{"id":921,"date":"2020-02-18T10:36:46","date_gmt":"2020-02-18T05:06:46","guid":{"rendered":"https:\/\/medicineplexus.com\/?p=921"},"modified":"2020-02-18T10:36:46","modified_gmt":"2020-02-18T05:06:46","slug":"blood-substitutes","status":"publish","type":"post","link":"https:\/\/medicineplexus.com\/blood-substitutes\/","title":{"rendered":"Blood Substitutes"},"content":{"rendered":"\n
Blood Substitutes<\/strong><\/p>\n\n\n\n Blood is a special type of connective tissue that is composed of white cells, red cells, platelets, and plasma.<\/p>\n\n\n\n Plasma is the extracellular material made up of water, salts, and various proteins that, along with platelets, encourages blood to clot.<\/p>\n\n\n\n Functions of blood<\/p>\n\n\n\n A blood substitute <\/em><\/strong>(also called artificial blood or blood surrogates)<\/em><\/strong><\/p>\n\n\n\n Challenges for blood transfusion:<\/p>\n\n\n\n Ideal blood substitute<\/strong><\/p>\n\n\n\n Types of blood substitute:<\/strong><\/p>\n\n\n\n Can serve as<\/p>\n\n\n\n 1. Plasma Expanders: <\/strong>These are compounds, which are either entirely synthetic or processed from natural proteins that serve as infusion solutions which expand intravascular volume.<\/p>\n\n\n\n 2. RBC Substitutes:<\/strong><\/p>\n\n\n\n Modified Haemoglobins – these are essentially human haemoglobins extracted from outdated blood.<\/p>\n\n\n\n Perflurocarbons – Synthetic organic compounds that can take over perfusion<\/p>\n\n\n\n Plasma Expanders:<\/strong><\/p>\n\n\n\n Crystalloids:<\/strong><\/p>\n\n\n\n normal saline, dextrose and ringer lactate.<\/p>\n\n\n\n Can serve as volume substitutes and maintain plasma osmolarity.<\/p>\n\n\n\n Colloid:<\/strong><\/p>\n\n\n\n plasma expanders encompass a wide range of substances.<\/p>\n\n\n\n These compounds hold water and actually expand volume over the amount infused.<\/p>\n\n\n\n Gelatin:<\/strong><\/p>\n\n\n\n These are modified gelatin polymers, which were among the earliest used colloid expanders, but are now being phased out due to an inherent risk of anaphylaxis.<\/p>\n\n\n\n Dextran:<\/strong><\/p>\n\n\n\n This is a newer generation of colloid expander which uniquely not only expands plasma volume, but also serves to decrease blood viscosity, thereby improving perfusion.<\/p>\n\n\n\n Hydroxyethyl Starch (HES):<\/strong><\/p>\n\n\n\n This is a polymerized form of plant starch which is structurally similar to glycogen and is therefore the safest of the plasma expanders.<\/p>\n\n\n\n Albumins and Purified Protein Derivatives:<\/strong><\/p>\n\n\n\n These are prepared by fractionating albumin and other proteins from pooled human blood and then sterilizing and processing the albumin so that it is iso-osmolar with plasma. These carry the greatest risk of anaphylaxis.<\/p>\n\n\n\n Uses of plasma expanders<\/strong><\/p>\n\n\n\n General indications include hypovolemia, loss of blood or plasma or post-surgical states.<\/p>\n\n\n\n Issues with use of plasma expanders <\/strong><\/p>\n\n\n\n PFC based blood substitutes<\/strong><\/p>\n\n\n\n Advantages of PFC emulsions<\/strong><\/p>\n\n\n\n Disadvantages of perfluorocarbons (PFC) emulsions<\/strong><\/p>\n\n\n\n Examples of PFC based products<\/strong><\/p>\n\n\n\n Hemoglobin Based Oxygen Carriers<\/strong><\/p>\n\n\n\n The idea of using purified haemoglobin as a possible universal substitute for red blood cells has been around for nearly a century, based on haemoglobin\u2019s unique oxygenbinding property and the perceived lack of antigenicity. Each normal adult haemoglobin molecule has a tetrameric structure, comprising two alfa and two beta polypeptide chains. Each unit is linked by an iron ion (Fe2+) to a haem molecule, where the oxygen is fixed.<\/p>\n\n\n\n Advantages of HBOC<\/strong><\/p>\n\n\n\n Disadvantages of HBOC<\/strong><\/p>\n\n\n\n Nanobiotechnology<\/strong><\/p>\n\n\n\n Since we can not use free Hb which have several ADRs we should stabilize that Hb with various procedures and then only it can be used.<\/p>\n\n\n\n Nanodimension Complete Artificial RBC.<\/p>\n\n\n\n Concerns<\/strong><\/p>\n\n\n\n Free radical generation, Iron deposition, Antigenicity<\/p>\n\n\n\n Examples of HBOCs<\/strong><\/strong><\/p>\n\n\n\n Platelet substitutes<\/strong><\/p>\n\n\n\n Blood products grown from stem cells<\/strong><\/p>\n\n\n\n Other potential techniques<\/strong><\/p>\n\n\n\n Dendrimers<\/strong><\/p>\n\n\n\n Biodegradable micelles<\/strong><\/p>\n\n\n\n Placental umbilical cord blood<\/strong><\/p>\n\n\n\n Respirocytes<\/strong><\/p>\n\n\n\n Blood Substitutes Blood is a special type of connective tissue that is composed of white cells, red cells, platelets, and plasma. Plasma is the extracellular material made up of water, salts, and various proteins that, along with platelets, encourages blood to clot. Functions of blood Respiration Nutrition Excretion Coagulation Maintenance of normal acid base balance[…]\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"","_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","footnotes":""},"categories":[3],"tags":[],"_links":{"self":[{"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/posts\/921"}],"collection":[{"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/comments?post=921"}],"version-history":[{"count":0,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/posts\/921\/revisions"}],"wp:attachment":[{"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/media?parent=921"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/categories?post=921"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/medicineplexus.com\/wp-json\/wp\/v2\/tags?post=921"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Oxygent<\/strong><\/td> Currently approved for Phase II Trials in US and Europe, developed to \u2193 need for donor blood during surgery. Done well overall in most clinical trials, but recently, a cardiac surgery study found participants to be slightly more likely to suffer if treated with Oxygent rather than by standard care.<\/td><\/tr> Oxycyte<\/strong><\/td> Currently approved for Phase II-b Trials in the US. Targeted as an oxygen therapeutic, with successful small scale open label human trials treating traumatic brain injury.<\/td><\/tr> PHER-O2<\/strong><\/td> In research<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n Perftoran<\/strong><\/td> Approved in Russian<\/strong> and Mexico. Distributed by KEM Laboratory (Mexico). Its infusion alleviates symptoms of ischemia at different types of occlusion vessels disease, improves grafting in plastic surgery, diminishes inflammation and prevents rejection of transplants, inhibits retro-virus infection development. Local Perftoran applications are able to accelerate wounds and ulcers healing.<\/td><\/tr> Fluosol-DA<\/strong><\/td> withdrawn in 1994 due to usage complexity, limited clinical benefit and complications<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n Hemopure<\/strong> Polymerised bovine Hb<\/strong><\/td> Currently approved for Phase III trials in US and was more widely approved in South Africa. Many safety measures are taken to render free of pathogens, including herd control and monitoring.<\/strong><\/td><\/tr> Oxyglobin<\/strong><\/td> Currently approved for veterinary use in US & Europe. Oxyglobin solution is the first & only oxygen therapeutic to be both US FDA and European Commission approved for veterinary use. Oxyglobin has been used primarily for blood transfusions and for treatment of anaemia in dogs<\/em>.<\/strong><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n PolyHeme<\/strong> Polymerised pyridoxilatedHB<\/td> Unique human HBOC in development for the treatment of urgent, large volume blood loss in trauma and surgical settings. It is the only blood substitute that has completed a Phase III trial. <\/strong>Also, free haemoglobin can be taken up by the kidney, causing dysfunction and failure, similar to a hemolytic transfusion reaction<\/td><\/tr> Optro<\/strong> Cross-linked HB from genetically modified E. coli<\/td> Phase II trials completed.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n Hemospan<\/strong> Conjugated human Hb<\/td> Hemospan is currently in Phase II trials in the US. It is produced in powder form, which can then be mixed into liquid form and transfused immediately, regardless of a patient\u2019s blood type. This technology relies on coupling with polyethylene glycol (PEG) <\/strong>to eliminate the toxicity associated with free haemoglobin.<\/td><\/tr> Hemolink<\/strong> Cross-linked human Hb<\/td> Phase 3 trials completed. Abandoned due to cardiac toxicity.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n