Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002871 (anemia)
 52,094 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sixty consecutive patients undergoing elective open-heart surgery were prospectively enrolled in a study to compare the efficacy of 3 different antifibrinolytic drugs to reduce postoperative bleeding and to reduce homologous blood requirements in combination with blood-saving techniques and restrictive indications for blood transfusion. The patients were randomized to 1 of 4 intraoperative treatment regimens: 1) control (no antifibrinolytic therapy); 2) epsilon-aminocaproic acid (10 g IV at induction of anesthesia, followed by infusion of 2 g/h for 5 hours); 3) tranexamic acid (10 mg/kg IV within 30 minutes after induction of anesthesia, followed by infusion of 1 mg/kg per hour for 10 hours); or 4) high-dose aprotinin (2 million KIU IV at induction of anesthesia and 2 million KIU added to the extracorporeal circuit, followed by infusion of 500 thousand KIU/h during surgery). Hemoconcentration and reinfusion of blood drained from the operative field and the extracorporeal circuit after operation were used in all patients. Indications for blood transfusion were hypotension, tachycardia, or both, with hemoglobin values < 8.5 g/dL; or severe anemia with hemoglobin values < 7 g/dL. Compared with the blood loss in the control group, patients receiving aprotinin and epsilon-aminocaproic acid showed significantly less postoperative blood loss at 1 hour (control, 128 +/- 94 mL; aprotinin, 54 +/- 47 mL, p = 0.01; and epsilon-aminocaproic acid, 69 +/- 35 mL, p = 0.03); this trend continued at 24 hours after operation (control, 724 +/- 280 mL; aprotinin, 344 +/- 106 mL, p < 0.0001; and epsilon-aminocaproic acid, 509 +/- 148 mL, p = 0.01). Aprotinin was significantly more efficient than epsilon-aminocaproic acid (p=0.002). Tranexamic acid did not have a statistically significant effect on blood loss. Homologous blood requirements were not significantly different among the groups; postoperative hematologic values and coagulation times were also comparable. Despite the efficacy of aprotinin and epsilon-aminocaproic acid shown in the present study, the blood requirements were not significantly different from those that are found when transfusions are restricted, autotransfusions are used, and blood from the operative field and extracorporeal circuit is concentrated and reinfused. Therefore, intraoperative antifibrinolysis may not be indicated in routine cardiac surgery when other blood-saving techniques are adopted.
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PMID:Intraoperative antifibrinolysis and blood-saving techniques in cardiac surgery. Prospective trial of 3 antifibrinolytic drugs. 758 Mar 60

Members of Jehovah's Witnesses refuse blood transfusions and blood products under any circumstances. Because of an improvement in blood salvage techniques in our centre, they are not excluded from open-heart surgery. In recent years recombinant human erythropoietin (rhEPO) has been applied to correct perioperative anemia in these patients. METHODS. Seventeen members of Jehovah's Witnesses who were more than 18 years of age were operated on using various blood salvage technique, e.g., haemoseparation and a high dose of Aprotinin. We present the first three patients treated with 4 x 500 U of i.v. rhEPO/kg body wt. given within 11 days preoperatively. Thirteen of the patients operated on had elevated preoperative risk factors, for instance poor left ventricle, severe aortic valve stenosis, metabolic syndrome, age older than 70 years, etc. In other centres that perform cardiac operations on members of Jehovah's Witnesses, these risk factors represent contraindications for open-heart surgery in these patients. RESULTS. Patients with rhEPO treatment showed a preoperative hematocrit increase of 7 Vol.% within 10 days and no postoperative complications. At the 6th postoperative hour the hematocrit returned to the starting values; in patients without rhEPO, however, the hematocrit generally had not increased to preoperative values even by the 8th day after operation. In 9 patients with preoperative elevated risk factors and a postoperative relative decrease in hematocrit below 33% we observed an uncomplicated postoperative period. Four patients with these risk factors, a pronounced decrease in hematocrit and blood loss postoperatively had various severe complications. CONCLUSIONS. Preoperative treatment with a high dose of rhEPO to enhance the hematocrit and maturity by precursor red blood cells in patients with a hematocrit below 45 Vol.% is a possibility to compensate for the blood loss perioperatively and to avoid complications from a decrease in oxygen transport capacity. The anaemia and high blood loss postoperatively are the main causes for a slightly elevated operation risk in members of Jehovah's Witnesses in all heart centres that perform cardiac operations on these patients. Nevertheless, Jehovah's Witnesses should be not excluded from cardiac operations, since open-heart surgery without use of homologous blood is becoming a routine procedure.
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PMID:[Operations with a heart-lung machine in adult members of Jehovah's Witnesses]. 778 54

Bleeding remains a complication of certain complex surgical procedures, particularly those cardiac operations associated with long bypass times and profound hypothermia. Clinical and novel experimental strategies to reduce bleeding and the need for blood and blood-product transfusions are the focus of this review. Preoperative assessment of the patient will identify drug-induced, acquired, or inherited coagulation defects that may contribute to this problem. The main attention is directed to the perioperative period, and broad areas discussed include the preoperative use of erythropoietin to increase red blood cell mass, autologous donation either preoperatively or before bypass, autotransfusion/hemofiltration, and acceptance of relative anemia both during the operation and into the postoperative period. A further, often overlooked, management strategy in treating major coagulopathies is the consideration of the cost and half-lives of the coagulation factors in individual blood components. Prevention of bleeding has become possible both by manipulation of the control of coagulation and inflammatory processes and by the introduction of pharmacologic agents such as aprotinin. Aprotinin is widely used and has proven efficacy in the management of excess bleeding. It is a serine protease inhibitor and has several possible mechanisms of action, including inhibition of the plasma enzyme systems activated by contact with the foreign surface of the bypass circuit and preservation of platelet function. Safety issues include the possibility of hypersensitivity and anaphylactic reaction on a second exposure. Concerns that aprotinin may induce a prothrombotic or coagulant state have no basis in theory or any good evidence in the current literature. A recent study specifically sought to identify the presence of disseminated microvascular platelet-fibrin thrombi present at autopsy in patients who had received aprotinin therapy. The study concluded that diffuse platelet-fibrin thrombi were not a direct complication of aprotinin therapy. Finally, modern molecular biology has led to the recent development of an inhibitor for factor IXa that competitively replaced IXa in the intrinsic complex and blocked the conversion of factor X to factor Xa. This compound is under investigation in animal studies. These have so far shown efficacy in reducing blood loss after bypass in comparison with standard heparin anticoagulation.
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PMID:Management of bleeding complications in redo cardiac operations. 956 96

There is still no alternative that is as effective or as well tolerated as blood; nevertheless, the search for ways to conserve, and even eliminate blood transfusion, continues. Based on hemoglobin levels, practice guidelines for the use of perioperative transfusion of red blood cells in patients undergoing coronary artery bypass grafting have been formulated by the National Institutes of Health and the American Society of Anesthesiologists. However, it has been argued that more physiologic indicators of adequacy of oxygen delivery should be used to assess the need for blood transfusion. Methods used for conserving blood during surgery include autologous blood donation, acute normovolemic hemodilution and intra- and postoperative blood recovery and reinfusion. The guidelines for the use of autologous blood transfusion are controversial and it does not appear to be cost effective compared with allogeneic blood transfusion in patients undergoing cardiac surgery. Similarly, the cost effectiveness of intra- and postoperative blood recovery and reinfusion need further evaluation. Treatment with recombinant human erythropoietin (rhEPO) remains unapproved in the US for patients undergoing cardiac or vascular surgery, but it is a valuable adjunct in Jehovah's Witness patients, for whom blood is unacceptable. The characterization of darbepoetin alfa, a novel erythropoiesis stimulating protein with a 3-fold greater plasma elimination half-life compared with rhEPO, is an important advance in this field. Darbepoetin alfa appears to be effective in treating the anemia in patients with renal failure or cancer and trials in patients with surgical anemia are planned. Desmopressin has been used to effectively reduce intraoperative blood loss. Topical agents to prevent blood loss, such as fibrin glue and fibrin gel, and agents that alter platelet function, such as aspirin (acetylsalicylic acid) or dipyridamole, need further evaluation in patients undergoing cardiac surgery. Aprotinin has been shown to preserve hemostasis and reduce allogeneic blood exposure to a greater extent than the antifibrinolytic agents tranexamic acid and aminocaproic acid. Controlled clinical trials comparing the costs of these agents with clinical outcomes, along with tolerability profiles in patients at risk for substantial perioperative bleeding are needed.
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PMID:Transfusion medicine : support of patients undergoing cardiac surgery. 1472 16