***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Background Abnormal bleeding after cardiopulmonary bypass ( CPB ) is a common complication of cardiac surgery , with important health and economic consequences . Coagulation test – based algorithms may reduce transfusion of non-erythrocyte allogeneic blood in patients with abnormal bleeding . Methods The authors performed a r and omized prospect i ve trial comparing allogeneic transfusion practice s in 92 adult patients with abnormal bleeding after CPB . Patients with abnormal bleeding  were r and omized to one of two groups : a control group following individual anesthesiologist ’s transfusion practice s and a protocol group using a transfusion algorithm guided by coagulation tests . Results Among 836 eligible patients having all types of elective cardiac surgery requiring CPB , 92 patients developed abnormal bleeding after CPB ( incidence , 11 % ) . The transfusion algorithm group received less allogeneic fresh frozen plasma in the operating room after CPB ( median , 0 units ; range , 0–7 units ) than the control group ( median , 3 units ; range , 0–10 units ) ( P = 0.0002 ) . The median number of platelet units transfused in the operating room after CPB was 4 ( range , 0–12 ) in the algorithm group compared with 6 ( range , 0–18 ) in the control group ( P = 0.0001 ) . Intensive care unit ( ICU ) mediastinal blood loss was significantly less in the algorithm group . Multivariate analysis demonstrated that transfusion algorithm use result ed in reduced ICU blood loss . The control group also had a significantly greater incidence of surgical reoperation of the mediastinum for bleeding ( 11.8%vs . 0%;P = 0.032 ) . Conclusions Use of a coagulation test – based transfusion algorithm in cardiac surgery patients with abnormal bleeding after CPB  reduced non-erythrocyte allogeneic transfusions in the operating room and ICU blood loss Introduction : The current investigation aim ed to study the efficacy of hemostatic therapy guided either by conventional coagulation analyses or point-of-care ( POC ) testing in coagulopathic cardiac surgery patients . Methods : Patients undergoing complex cardiac surgery were assessed for eligibility . Those patients in whom diffuse bleeding was diagnosed after heparin reversal or increased blood loss during the first 24 postoperative hours were enrolled and r and omized to the conventional or  POC  group . Thromboelastometry and whole blood impedance aggregometry have been performed in the POC group . The primary outcome variable was the number of transfused units of packed erythrocytes during the first 24 h after inclusion . Secondary outcome variables included postoperative blood loss , use and costs of hemostatic therapy , and clinical outcome parameters . Sample size analysis revealed a sample size of at least 100 patients per group . Results : There were 152 patients who were screened for eligibility and 100 patients were enrolled in the study . After r and omization of 50 patients to each group , a planned interim analysis revealed a significant difference in erythrocyte transfusion rate in the conventional compared with the POC group [ 5 ( 4;9 ) versus 3 ( 2;6 ) units [ median ( 25th and 75th percentile ) ] , P < 0.001 ] . The study was terminated early . The secondary outcome parameters of fresh frozen plasma and platelet transfusion rates , postoperative mechanical ventilation time , length of intensive care unit stay , composite adverse events rate , costs of hemostatic therapy , and 6-month mortality were lower in the POC group . Conclusions : Hemostatic therapy based on POC testing reduced patient exposure to allogenic blood products and provided significant benefits with respect to clinical outcomes BACKGROUND Using algorithms based on point of care coagulation tests can decrease blood loss and blood component transfusion  after cardiac surgery . We wished to test the hypothesis that a management algorithm based on near-patient tests would reduce blood loss and blood component use after routine coronary artery surgery with cardiopulmonary bypass when compared with an algorithm based on routine laboratory assays or with clinical judgement . METHODS Patients ( n=102 ) undergoing elective coronary artery surgery with cardiac bypass were r and omized into two groups . In the point of care group , the management algorithm was based on information provided by three devices , the Hepcon , thromboelastography and the PFA-100 platelet function analyser . Management in the laboratory test group depended on rapidly available laboratory clotting tests and transfusion of haemostatic blood components only if specific criteria were met . Blood loss and transfusion was compared between these two groups and with a retrospective case-control group ( n=108 ) , in which management of bleeding had been according to the clinician 's discretion . RESULTS All three groups had similar median blood losses . The transfusion of packed red blood cells ( PRBCs ) and blood components was greater in the clinician discretion group ( P<0.05 ) but there was no difference in the transfusion of PRBCs and blood components between the two algorithm-guided groups . CONCLUSION Following algorithms based on point of care tests or on structured clinical practice with st and ard laboratory tests does not decrease blood loss , but reduces the transfusion of PRBCs and blood components after routine cardiac surgery , when compared with clinician discretion . Cardiac surgery services should use transfusion guidelines based on laboratory-guided algorithms , and the possible benefits of point of care testing should be tested against this st and ard We set out to determine if the heparinase-modified thrombelastogram using anticoagulated blood from patients during cardiac surgery could guide treatment with haemostatic components . In 60 patients a simple algorithm predicted a possible 60 - 80 % decrease in the use of  haemostatic components .  In a second series , 30 patients were allocated to receive components using this intra-operative algorithm and 30 using clinical criteria and laboratory-based tests . Ten patients in the clinical group received a total of 16 units of fresh frozen plasma and nine platelet concentrates compared with five patients transfused with five units of fresh frozen plasma and one platelet concentrate in the algorithm group . Twelve-hour chest tube losses [ algorithm group 470 ( 295 - 820 ) ml , clinical ly managed group 390 ( 240 - 820 ) ml ( median , quartile values ) ] were not different between groups despite the threefold reduction in the use of haemostatic products , showing that intra-operative monitoring of coagulation in the anticoagulated patient can be used to guide treatment BACKGROUND Thromboelastometric evaluation of coagulation might be useful for prediction and management of bleeding after paediatric cardiac surgery . We tested the hypothesis that the use of a thromboelastometry-guided algorithm for blood product management reduces blood loss and transfusion requirements . METHODS We studied 78 patients undergoing paediatric cardiac surgery with cardiopulmonary bypass ( CPB ) for the initial 12 h after operation . Stepwise multiple linear regression was used to develop an algorithm to guide blood product transfusions . Thereafter , we r and omly assigned 100 patients to conventional or algorithm-guided blood product management , and assessed bleeding and red cell transfusion requirements . RESULTS CPB time , post-bypass rotational thromboelastometry ( ROTEM ( ® ) ) EXTEM amplitude at 10 min ( A10 ) , and FIBTEM-A10 were independently associated with chest tube drainage volume during the initial 12 h after operation . Discriminative analysis determined cut-off values of 30 mm for EXTEM-A10 and 5 mm for FIBTEM-A10 , and estimated optimal intraoperative fresh-frozen plasma and platelet concentrate transfusion volumes . Thromboelastometry-guided post-bypass blood product management significantly reduced postoperative bleeding ( 9 vs 16 ml kg(-1 ) , P<0.001 ) and packed red cell transfusion requirement ( 11 vs 23 ml kg(-1 ) , P=0.005 ) at 12 h after surgery , and duration of critical care stay ( 60 vs 71 h , P=0.014 ) . CONCLUSIONS Rotational thromboelastometry-guided early haemostatic intervention by rapid intraoperative correction of EXTEM-A10 and FIBTEM-A10 reduced blood loss and red cell transfusion requirements after CPB , and reduced critical care duration in paediatric cardiac surgical patients . CLINICAL TRIAL REGISTRATION UMIN Clinical Trials Registry UMIN000006832 ( December 4 , 2011 ) OBJECTIVE To investigate if the use of preoperative platelet function testing ( PFT ) as part of a transfusion algorithm reduced blood product usage in coronary artery bypass surgery ( CABG ) . DESIGN Prospect i ve , r and omized , controlled trial . SETTING A cardiothoracic hospital . PARTICIPANTS 249 patients having CABG surgery . INTERVENTIONS The patients were allocated r and omly to PFT preoperatively with Multiple Electrode Aggregometry ( MEA , Group A ) , TEG PlateletMapping ( PM , Group B ) or none ( control , Group C ) . Post-bypass bleeding management was determined by a transfusion algorithm . MEASUREMENTS AND MAIN RESULTS The primary outcome measure was blood product transfusion in the first 48 hours post-surgery . There was a significant reduction in all blood product transfusion between Groups A ( MEA ) and B ( PM ) and Group C ( control ) ( median number of units transfused , 2 (A)/2 (B)/ 4(C ) , p=0.02 ) . Those in A and B received fewer units of red cells ( median number of units , 0 (A)/1 ( B ) /2 ( C ) , p=0.006 ) and fresh frozen plasma than the control Group C ( median number of units , 0 (A)/0 (B)/2 ( C ) , p<0.001 ) , without receiving significantly more units of platelets ( median number of units , 1 (A)/1 (B)/0 ( C ) , p=0.11 ) . In those who had taken an adenosine disphosphate (ADP)-receptor antagonist within 5 days ( n=173 ) , these results were amplified , and additionally , there was a significant cost saving ( median cost , A=£1738.53 , B=£1736.96 , C=£3191.80 p=0.006 ) . CONCLUSION Preoperative PFT as part of a point-of-care testing-based transfusion algorithm led to a reduction in blood transfusion . There is a potential cost saving in those who have taken an ADP-receptor antagonist within 5 days BACKGROUND The protease inhibitor aprotinin reduces hemostatic activation and blood loss after cardiac operations . The aim of the present study was to investigate the influence of two different aprotinin doses on hemostatic activation and to identify the most effective dose to reduce the postoperative bleeding tendency . METHODS In a prospect i ve , r and omized , double-blind clinical trial , 230 patients scheduled for routine open heart operations received either high-dose ( group H ) or low-dose ( group L ) aprotinin . Primary outcome measures were the level of F(1 + 2 ) prothrombin fragments as a marker of thrombin generation , the level of D-dimers as an indicator of fibrinolysis , and the amount of postoperative blood loss . Allogeneic blood transfusion was recorded as a secondary outcome measure . RESULTS Aprotinin plasma concentrations 5 minutes after the onset of cardiopulmonary bypass were 166 + /- 45 kallikrein inactivator units per milliliter in group H and 118 + /- 30 kallikrein inactivator units per milliliter in group L ( p < 0.05 ) . Fibrinolytic activation was reduced significantly in group H compared with group L : the level of D-dimers at the end of CPB was 1,027 + /- 781 ng/mL and 1,977 + /- 1,001 ng/mL , respectively , in the two groups ( p < 0.05 ) . However , thrombin generation ( F(1 + 2 ) fragments ) did not differ between the two groups ( 7.4 + /- 3.5 nmol/L in group H and 8.6 + /- 4.3 nmol/L in group L ) . Twenty-four-hour postoperative blood loss was 663 + /- 461 mL in group H compared with 877 + /- 513 mL in group L ( p < 0.05 ) , and the corresponding allogeneic blood requirement was 1.3 + /- 1.9 U in group H and 1.9 + /- 2.3 U in group L ( p < 0.05 ) . CONCLUSIONS A high-dose aprotinin regimen was significantly more effective than a low-dose regimen in attenuating fibrinolysis and reducing the bleeding tendency and allogeneic blood requirements , but not in reducing F(1 + 2 ) prothrombin fragments .  High-dose aprotinin therapy appears to be superior to low-dose therapy Platelet function can be easily measured as time to peak ( TP ) by Sonoclot Coagulation & Platelet Function Analyzer ( Sienco Inc. , Morrison , CO ) analysis . However a correlation between Sonoclot analysis and platelet aggregation , which is accepted as a test of platelet function , has not been established . In this study , we compared TP and collagen-induced whole blood platelet aggregation in 15 patients undergoing cardiac surgery . Two or three blood sample s were r and omly obtained from each patient before and after cardiopulmonary bypass ( CPB ) .  Sonoclot analysis , collagen-induced whole blood aggregation , and laboratory 
    Output:
    
Routine use of viscoelastic point-of-care tests did not improve important clinical outcomes beyond transfusion in adults undergoing cardiac surgery