***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Objective : Perioperative transfusion has adverse effects in adults undergoing cardiac surgery . We sought to investigate whether greater use of blood and blood products might be an independent predictor of prolonged postoperative recovery , indicated by duration of  mechanical ventilation ( DMV ) , after reparative infant heart surgery . Design : Secondary analysis of prospect ively collected data from two r and omized trials of hematocrit strategy during cardiopulmonary bypass in infant heart surgery to explore the association of DMV with perioperative transfusion and other variables . Setting : Tertiary pediatric hospital . Patients : Two hundred seventy infants undergoing two ventricle corrective cardiac surgery without aortic arch reconstruction . Measurements and Main Results : In univariable analyses , longer DMV was associated with younger age and lower weight at surgery , diagnostic group , and higher intraoperative and postoperative blood product transfusion ( each p < .001 ) . In multivariable proportional hazard regression , longer total support time and greater intraoperative and early postoperative blood products per kg were the strongest predictors of longer DMV . Patients in the highest tertile of intraoperative blood products per kg had an instantaneous risk of being extubated approximately half that of patients in the lowest tertile ( hazard ratio , 0.51 ; 95 % confidence interval , 0.35 , 0.73 ) . Patients who received any blood  products on postoperative day 1 , compared with those who did not , had a hazard ratio for extubation of 0.65 ( 95 % confidence interval , 0.50 , 0.85 ) . Conclusions : In this exploratory secondary analysis of infants undergoing two ventricular repair of congenital heart disease without aortic arch obstruction , greater intraoperative and early postoperative blood transfusion emerged as potential important risk factors for longer DMV . Future prospect i ve clinical trials are needed to determine whether reduction in blood product administration hastens postoperative recovery after infant heart surgery BACKGROUND Fibrinogen supplementation is increasingly recommended with the use of rotational thromboelastometry ( ROTEM ) . However , data regarding the paediatric population are sparse . OBJECTIVE We aim ed to assess the relationship between plasma fibrinogen concentration and postoperative blood loss in children undergoing cardiac surgery . DESIGN Retrospective analysis . SETTING Data prospect ively recorded in our departmental data base between September 2010 and January 2012 . PATIENTS Data from 156 children scheduled for congenital heart surgery with ROTEM performed at the end of cardiopulmonary bypass ( CPB )  were analysed . INTERVENTION None . MAIN OUTCOME MEASURES Abnormal bleeding was defined as blood loss that exceeded 10 % of total blood volume within the first 6 postoperative hours . Logistic regression analyses were used to determine variables associated with bleeding . Correlation analyses and receiver operating characteristic ( ROC ) curves were design ed to evaluate the relationship between blood loss and plasma fibrinogen concentration or ROTEM variables , if relevant . RESULTS Thirty-six children were considered as ‘ bleeders ’ and 120 as ‘ nonbleeders ’ . Univariate and multivariate logistic regression analysis revealed time for wound closure , clot formation time , maximal clot firmness ( MCF ) and plasma fibrinogen concentration as variables independently associated with postoperative bleeding . MCF was best correlated with plasma fibrinogen concentration . ROC curves for blood loss versus fibrinogen concentration and MCF showed that a plasma fibrinogen concentration of 1.5 g l−1 and a MCF value 3 mm or less could be used to predict blood loss . CONCLUSION Post-CPB plasma fibrinogen concentration significantly influences blood loss in children undergoing cardiac surgery . A fibrinogen concentration of at least 1.5 g l−1 or a MCF of at least 3 mm should accurately predict excessive blood loss in cardiac surgery children . Further prospect i ve trials are needed to assess the effect of fibrinogen supplementation on postoperative blood loss in this population BACKGROUND : The inflated costs and documented deleterious effects of excess perioperative transfusion have led to the investigation of targeted coagulation factor replacement strategies . One particular coagulation factor of interest is factor I ( fibrinogen ) . Hypofibrinogenemia is typically tested for using time-consuming st and ard laboratory assays . The thrombelastography (TEG)-based functional fibrinogen level ( FLEV ) provides an assessment of whole blood clot under platelet inhibition to report calculated fibrinogen levels in significantly less time . If FLEV values obtained on cardiopulmonary bypass ( CPB ) during rewarming are similar to values obtained immediately after the discontinuation of CPB , then rewarming values could be used for preemptive ordering of appropriate blood product therapy . METHODS : Fifty-one cardiac surgery patients were enrolled into this prospect i ve nonr and omized study to compare rewarming fibrinogen values with postbypass values using TEG FLEV assays .  Baseline , rewarming , and postbypass fibrinogen values were recorded for all patients using both st and ard laboratory assay ( Clauss method ) and FLEV . Mixed-effects regression models were used to examine the change in TEG FLEV values over time . Bl and -Altman analysis was used to examine bias and the limits of agreement ( LOA ) between the st and ard laboratory assay and FLEVs . RESULTS : Forty-nine patients were included in the analysis . The mean FLEV value during rewarming was 333.9 mg/dL compared with 332.8 mg/dL after protamine , corresponding to an estimated difference of −1.1 mg/dL ( 95 % confidence interval [ CI ] , −25.8 to 23.6 ; P = 0.917 ) . Rewarming values were available on average 47 minutes before postprotamine values . Bl and -Altman analysis showed poor agreement between FLEV and st and ard assays : mean difference at baseline was 92.5 mg/dL ( 95 % CI , 71.1 to 114.9 ) , with a lower LOA of −56.5 mg/dL ( 95 % CI , −94.4 to −18.6 ) and upper LOA of 242.4 mg/dL ( 95 % CI , 204.5 to 280.3 ) . The difference between assays increased after CPB and persisted after protamine administration . CONCLUSIONS : Our results revealed negligible change in FLEV values from the rewarming to postbypass periods , with a CI that does not include clinical ly meaningful differences . These findings suggest that rewarming sample s could be utilized for ordering fibrinogen-specific therapies before discontinuation of CPB . Mean FLEV values were consistently higher than the reference st and ard at each time point . Moreover , bias was highly heterogeneous among sample s , implying a large range of potential differences between assays for any 1 patient Background . In newborns and small infants undergoing cardiac surgery with cardiopulmonary bypass ( CPB ) and blood priming , it is unclear whether there is reduced blood loss if fresh frozen plasma ( FFP ) is added to the CPB priming volume . This single‐centre , r and omized trial tested the hypothesis that the administration of FFP after CPB ( late FFP group ) is superior to FFP priming ( early FFP group ) in terms of postoperative bleeding and overall red blood cell ( RBC ) transfusion . Methods . Seventy‐three infants weighing < 10 kg were r and omly allocated to receive FFP to supplement RBCs in the CPB priming solution ( n=36 ) or immediately after CPB ( n=37 ) . The primary endpoint was a difference in postoperative blood loss ; secondary endpoints included the amount of RBCs and FFP transfused through the first 48 postoperative hours . Results . All patients were included in the analysis . Patients in the late FFP arm had greater postoperative mean blood loss than patients in the early FFP arm [ 33.1 ( SD 20.6 ) vs 24.1 ( 12.9 ) ml kg‐1 ; P=0.028 ] , but no differences in transfusions were found . The subgroup of cyanotic heart disease patients had comparable results , but with greater use of RBCs in the late FFP group . Conclusions . In infants undergoing cardiac surgery , FFP in the priming solution appears slightly superior to late administration in terms of postoperative bleeding . Clinical trial registration : www . Clinical Trials.gov , NCT02738190 OBJECTIVES Acute acquired hypofibrinogenemia in children undergoing cardiac surgery is a major concern because it often results in perioperative bleeding and high rates of allogeneic blood transfusion . Fibrinogen concentrate has been proposed as an alternative to cryoprecipitate ( the gold st and ard therapy ) , with minimal infectious and immunologic risks . Our objective was to investigate the efficacy and safety of fibrinogen concentrate in children undergoing cardiac surgery . METHODS In this r and omized pilot study , patients were allocated to receive fibrinogen concentrate ( 60 mg/kg ) or cryoprecipitate ( 10 mL/kg ) if bleeding was associated with fibrinogen levels<1 g/dL after cardiopulmonary bypass weaning . The primary outcome was postoperative blood losses during the 48 hours after surgery . RESULTS A total of 63 patients were included in the study , 30 in the fibrinogen concentrate group and 33 in the cryoprecipitate group . The median 48-hour blood loss was not significantly different between the 2 groups ( 320 mL [ interquartile range , 157 - 750 ] vs 410 mL [ interquartile range , 215 - 510 ] , respectively ; P=.672 ) . After treatment , plasma fibrinogen concentration increased similarly following administration of both products . There were no differences in allogeneic blood transfusion after intervention treatment . CONCLUSIONS A large trial comparing fibrinogen concentrate and cryoprecipitate in the management of children with acute acquired hypofibrinogenemia during heart surgery is feasible . The preliminary results of our study showed that the use of fibrinogen concentrate was as efficient and safe as cryoprecipitate in the management of bleeding children undergoing cardiac surgery OBJECTIVE The present study was conducted to determine how children and adults differ ( it at all ) with respect to sensitivity to heparin activity and heparin-protamine interactions during cardiac surgery requiring cardiopulmonary bypass ( CPB ) . DESIGN A prospect i ve study of both children and adults undergoing CPB .  SETTING A tertiary care academic medical center between July 1992 and October 1994 . PARTICIPANTS Ninety patients who had cardiac or aortic arch surgery using CPB .  The median age of the entire study sample was 15.8 years ( range 2 months to 72 years ) . INTERVENTION Data were obtained using the Medtronic Hemotec Hepcon Hemostasis Management System ( Englewood , CO ) . An ex vivo  heparin dose-response ( HDR ) curve was generated for each patient before skin incision to determine the target heparin concentration ( THC ) needed to achieve an activated coagulation time ( ACT ) of at least 480 seconds . Protamine dose was determined on the basis of whole blood heparin concentration estimated by means of a heparin-protamine titration . MEASUREMENTS AND MAIN RESULTS The study population was divided into four groups based on age : infants ( < 1 year ) , preschool ( 1 to 5 years ) , school-age ( 5 to 14 years ) and adults ( > 14 years ) . The mean + /- SD THC for the preschool group was 4.0 + /- 1.1 ; for infants , 3.3 + /- 0.7 ; for school-age , 3.1 + /- 0.7 ; and for adults , 3.4 + /- 0.7 . The initial dose of heparin needed to achieve this THC ( mean + /- SD ) was significantly higher in infants ( 578 + /- 220 U/kg ) and preschool children ( 477 + /- 159 U/kg ) than in school-age children ( 327 + /- 57 U/kg ) and adults ( 332 + /- 64 U/kg ) . The ratio of protamine to heparin was significantly higher in adults ( 1.4 + /- 0.5 ) and school-age children ( 1.3 + /- 0.6 ) than in infants ( 1.1 + /- 0.7 ) and preschool children ( 1.1 + /- 0.4 ) . CONCLUSIONS Pre-school children are less sensitive to heparin but also display a wider range of sensitivity . The data in this study support the use of 300 U/kg of heparin before CPB in patients > or = 5 years but suggest that heparin requirements may be greater in the younger patient who may require as much as 500 U/kg to achieve what is believed to be an appropriate target heparin concentration for initiating CPB BACKGROUND : The majority of pediatric cardiac surgery patients receive blood transfusions . We hypothesized that the routine use of intraoperative thromboelastometry to guide transfusion decisions would reduce the overall proportion of patients receiving transfusions in pediatric cardiac surgery . METHODS : One hundred pediatric cardiac surgery patients were included in the study . Fifty patients ( study group ) were prospect ively included and compared with 50 procedure- and age-matched control patients ( control group ) .  In the study group , thromboelastometry , performed during cardiopulmonary bypass , guided intraoperative transfusions . Intraoperative and postoperative transfusions of pack 
    Output:
    
At present , literature data are too weak to define POCTs as a “ gold st and ard ” for the treatment of perioperative bleeding in pediatric cardiac surgery .
Nevertheless , introduction of POCTs into postoperative algorithms has shown to improve bleeding management , patient outcome , and cost efficiency