***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 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 OBJECTIVE Aortic surgical procedures requiring hypothermic circulatory arrest are associated with altered hemostasis and increased bleeding . In a r and omized clinical trial , we evaluated effects of thromboelastometrically guided algorithm on transfusion requirements . METHODS Fifty-six consecutive patients ( 25 with acute type A dissection ) undergoing aortic surgery with hypothermic circulatory arrest were enrolled in a r and omized trial during a 6-month period . Patients were r and omly allocated to treatment group ( n = 27 ) with thromboelastometrically guided transfusion algorithm or control group ( n = 29 ) with routine transfusion practice s ( clinical judgment-guided transfusion followed by transfusion according to coagulation test results ) . Primary end point was cumulative allogeneic blood units ( red blood cells , fresh-frozen plasma , and platelets ) transfused . RESULTS Transfusion of allogeneic blood was significantly reduced in the thromboelastometry group : median 9.0 units ( interquartile range , 2.0 - 30.0 units ) versus . 16.0 units ( 9.0 - 23.0 units , P = .02 ) . Most significant decrease was in the use of fresh-frozen plasma ( 3.0 units , 0 - 12.0 units , vs 8.0 units , 4.0 - 18.0 units , P = .005 ) . Postoperative blood loss ( 890 mL/d , 600 - 1250 mL/d vs 950 mL/d , 650 - 1400 mL/d , p = 0.5 ) and rate of surgical re-exploration ( 19 % vs 24 % , P = .7 ) were similar between groups . Thromboelastometrically guided algorithm significantly decreased need for massive perioperative transfusion ( odds ratio , 0.45 ; 95 % confidence interval , 0.2 - 0.9 ; P = .03 ) in multivariable logistic regression analysis . CONCLUSIONS Thromboelastometrically guided transfusion is associated with a decreased use of allogeneic blood units and reduced incidence of massive transfusion in patients undergoing aortic surgery with circulatory arrest 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 ) UNLABELLED Transfusion therapy after cardiac surgery is empirically guided , partly due to a lack of specific point-of-care hemostasis monitors . In a r and omized , blinded , prospect i ve trial , we studied cardiac surgical patients at moderate to high risk of transfusion . Patients were r and omly assigned to either a thromboelastography (TEG)-guided transfusion algorithm ( n = 53 ) or routine transfusion therapy  ( n = 52 ) for intervention after cardiopulmonary bypass . Coagulation tests , TEG variables , mediastinal tube drainage , and transfusions were compared at multiple time points . There were no demographic or hemostatic test result differences between groups , and all patients were given prophylactic antifibrinolytic therapy .  Intraoperative transfusion rates did not differ , but there were significantly fewer postoperative and total transfusions in the TEG group . The proportion of patients receiving fresh-frozen plasma ( FFP ) was 4 of 53 in the TEG group compared with 16 of 52 in the control group ( P < 0.002 ) . Patients receiving platelets were 7 of 53 in the TEG group compared with 15 of 52 in the control group ( P < 0.05 ) . Patients in the TEG group also received less volume of FFP ( 36 + /- 142 vs 217 + /- 463 mL ; P < 0.04 ) . Mediastinal tube drainage was not statistically different 6 , 12 , or 24 h postoperatively . Point-of-care coagulation monitoring using TEG result ed in fewer transfusions in the postoperative period . We conclude that the reduction in transfusions may have been due to improved hemostasis in these patients who had earlier and specific identification of the hemostasis abnormality and thus received more appropriate intraoperative transfusion therapy . These data support the use of TEG in an algorithm to guide transfusion therapy in complex cardiac surgery . IMPLICATION S Transfusion of allogeneic blood products is common during complex cardiac surgical procedures . In a prospect i ve , r and omized trial , we compared a transfusion algorithm using point-of-care coagulation testing with routine laboratory testing , and found the algorithm to be effective in reducing transfusion requirements BACKGROUND Allogenic blood transfusion may affect clinical outcomes negatively . Up to 20 % of blood transfusions in the United States are associated with cardiac surgery and so strategies to conserve usage are of importance . This study compares administration according to physician 's choice based on laboratory coagulation tests with application of a strict protocol based on the thromboelastograph ( TEG ) . METHODS Sixty-nine patients presenting for cardiac surgery were r and omised to either study or control groups . In the study group a strict protocol was followed covering usage of all blood products according to TEG patterns . In the control group , the physician directed product administration with reference to activated partial thromboplastin time ( APTT ) , international normalised ratio ( INR ) , fibrinogen and platelet count . Bleeding , re-sternotomy , minimum haemoglobin , intubation time , and ICU stay were documented . RESULTS TEG-based management reduced total product usage by 58.8 % in the study group but this was not statistically significant . This was associated with a statistically insignificant trend towards better short-term outcomes . CONCLUSIONS This pilot study suggests that a strict protocol for blood product replacement based on the TEG might be highly effective in reducing usage without impairing short-term outcome OBJECTIVE Bleeding and allogeneic transfusion remain constant problems in cardiac surgical procedures . In this study , we aim ed to test the role of a routine thromboelastography (TEG)-based algorithm on bleeding and transfusions in patients undergoing elective coronary artery bypass grafting ( CABG ) .  METHODS Patients ( n = 224 ) undergoing elective CABG with cardiopulmonary bypass  were prospect ively r and omized into two groups according to transfusion strategy : in group 1 ( clinician-directed transfusion , n = 110 ) need for blood transfusion was based on clinician 's discretion and st and ard coagulation tests and in group 2 ( TEG algorithm group , n = 114 ) kaolin-activated ( k ) TEG-based algorithm-guided perioperative transfusion management .  Transfusion , blood loss , and outcome data were recorded . RESULTS There were no differences in consumption of packed cell units , blood loss , re-exploration for bleeding , and early clinical outcome between the groups . Patients in the TEG group had significantly lower median units of fresh frozen plasma and platelets compared with the other group ( p = 0.001 ) . The median number of total allogeneic units transfused 
    Output:
    
Trial sequential analysis of continuous data on blood loss and dichotomous outcomes on transfusion of blood products suggested the benefits of a TEG/ROTEM-guided algorithm .
Conclusions TEG or ROTEM-guided transfusion strategies may reduce blood loss volume and the transfusion rates in adult patients undergoing cardiac surgery