***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: Background Diffuse microvascular bleeding remains a common problem after cardiac procedures .Systemic use of antifibrinolytic reduces the postoperative blood loss . The purpose of this study was to examine the effectiveness of local application of tranexamic acid to reduce blood loss after coronary artery bypass grafting ( CABG ) . Methods Thirty eight patients scheduled for primary isolated coronary artery bypass grafting were included in this double blind , prospect i ve , r and omized , placebo controlled study .Tranexamic acid ( TA ) group ( 19 patients ) received 1 gram of TA diluted in 100 ml normal saline . Placebo group ( 19 patients ) received 100 ml of normal saline only . The solution was purred in the pericardial and mediastinal cavities . Results Both groups were comparable in their baseline demographic and surgical characteristics . During the first 24 hours post-operatively , cumulative blood loss was significantly less in TA group ( median of 626 ml ) compared to Placebo group ( median of 1040 ml ) ( P = 0.04 ) . There was no significant difference in the post-op Packed RBCs transfusion between both groups ( median of one unit in each ) ( P = 0.82 ) . Significant less platelets transfusion required in TA group ( median zero unit ) than in placebo group ( median 2 units ) ( P = 0.03 ) . Apart from re-exploration for excessive surgical bleeding in one patient in TA group , no difference was found in morbidity or mortality between both groups . Conclusion Topical application of tranexamic acid in patients undergoing primary coronary artery bypass grafting led to a significant reduction in postoperative blood loss without adding extra risk to the patient Background Hidden blood loss is a major concern for patients undergoing hip surgery for intertrochanteric fracture . The objective of this study was to investigate whether tranexamic acid ( TXA ) could reduce postoperative hidden blood loss in patients undergoing hip surgery for intertrochanteric fracture . Methods A total of 77 patients with intertrochanteric fracture were enrolled in this r and omized controlled study . Patients received either 200 mL ( 1 g ) of TXA ( n = 37 ) or normal-saline ( NS ) ( n = 40 ) i.v . before hip surgery using proximal femoral nail anti-rotation ( PFNA ) . Hemoglobin and hematocrit levels were measured preoperatively and postoperatively at day 1 and 3 . Visible and hidden blood loss volumes were calculated at postoperative day 3 . Results On postoperative day 3 , the transfusion rate was significantly lower in the TXA group compared to the NS group , although mean hemoglobin and hematocrit levels were not significantly different between the two groups . However , the estimated hidden blood loss volume ( 210.09 ± 202.14 mL vs. 359.35 ± 290.12 mL ; P < 0.05 ) and total blood loss volume ( 279.35 ± 209.11 mL vs. 417.89 ± 289.56 mL ; P < 0.05 ) were significantly less in the TXA group compared to the NS group , respectively . Conclusion TXA significantly reduced postoperative hidden blood loss in patients with intertrochanteric fracture who underwent PFNA . ( Registration number : ChiCTR-INR-16008134 ) Objectives : We aim ed to determine whether ( 1 ) tranexamic acid ( TXA ) reduces the incidence of transfusion ( 2 ) TXA reduces the calculated blood loss , and ( 3 ) there are any observable differences in 30- and 90-day complications with TXA administration during arthroplasty for femoral neck fracture ( FNF ) . Design : Prospect i ve , double-blinded , r and omized controlled trial . Setting : Level 1 Academic Trauma Center . Patients / Participants : One hundred thirty-eight patients who presented with a low-energy , isolated , FNF ( AO 31B ) treated with either hemi- or total hip arthroplasty within 72 hours of injury were r and omized to either the TXA group ( 69 patients ) or placebo group ( 69 patients ) . Intervention : In the TXA group , patients received 2 doses of 15 mg/kg intravenous TXA dissolved in 100 mL of saline , each administered over 10 minutes ; 1 dose just before incision , and the second at wound closure . In the placebo group , 100 mL of saline solution was administered in a similar fashion . Perioperative care was otherwise st and ardized including conservative transfusion criteria . Main Outcome Measurements : Our primary outcome was to determine the proportion of patients who underwent blood transfusion during hospitalization . Secondary outcomes were calculated blood loss , number of units transfused during hospitalization , and incidence of adverse events at 30 and 90 days including thromboembolic event , wound complications , reoperation , hospital readmission , and all-cause mortality . Results : TXA reduced mean incidence of transfusion by 305 mL ( P = 0.0005 ) . There was a trend toward decreased transfusion rate in the TXA group ( 17 % vs. 26 % , P = 0.22 ) . TXA was safe with no differences in adverse events at 30 and 90 days . Conclusions : This r and omized clinical trial found that TXA administration safely reduced blood loss with a tendency for decreased transfusion rate and total blood product consumption for patients undergoing hip arthroplasty for acute FNF . More studies are needed to further ascertain the role of TXA in the management of patients with FNF . Level of Evidence : Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence Context : Pharmacological agents are used to reduce postoperative blood loss . Aims : To assess the effects of tranexamic acid on prevention of bleeding and requirement of blood transfusion after major hip and femoral surgeries . Setting s and Design : A prospect i ve , r and omized , double blinded study was conducted in the tertiary care teaching hospital . Methods : Ninety ASA grade I-II patients undergoing hip fracture surgery were included in this prospect i ve study . Forty-five patients received tranexamic acid ( TA ) given in a bolus dose of 500 mg 15 min before surgical incision followed by continuous infusion . The remaining , 45 patients were allocated as a control group . Postoperative bleeding ( volume of blood in the drain ) , percentage fall of hemoglobin , transfusions and complications were recorded . Results : Mean volume of blood in the drain was 39.33±10.09 ml ( mean±SD ) as compared to 91.11±17.61 ml in placebo group showing a P<0.001 . Mean percentage fall in Hb at day 0 was 2.99±3.45 in the study group as compared to 7.70±6.05 in the placebo group ( P<0.001 ) , and fall at day 2 in the study group was 0.35±0.74 , compared to 2.72±2.70 in the placebo group ( P<0.001 ) . The number of patients required blood transfusions were lower in the study group than in the placebo group ( P=0.01 ) . Conclusions : We conclude that tranexamic acid significantly reduces postoperative blood loss and transfusion requirements during major hip and femoral surgeries BACKGROUND Proximal Femoral shaft fractures are commonly associated with marked blood loss which can lead to postoperative acute anemia and some other complications . Tranexamic acid ( TA ) is an antifibrinolytic medication that reduces intra- and postoperative blood loss and transfusion requirements during some elective surgeries . The aim of this study is to evaluate the effect of intravenous Tranexamic acid ( TA ) on intraoperative blood loss and a subsequent need for transfusion in patients who were undergoing surgery for femoral shaft fractures in trauma setting . METHODS Thirty-eight ASA grade I-II patients undergoing proximal femoral shaft fracture surgery with intra medullary nailing were included in this double blind r and omized controlled clinical trial . They were allocated into two groups . Group I , the intervention group with eighteen patients received 15 mg/kg ( TA ) via intravenous infusion before surgical incision . Patients in the placebo group received an identical volume of normal saline .  Hemoglobin level was measured four hours before and after the surgeries . Postoperative blood loss and hemoglobin change as well as transfusion rates and volumes were compared between the two groups . RESULTS Mean Percentage fall in hemoglobin after surgery were 1.75±0.84 and 2.04±1.9 in the study and placebo groups , respectively ( P=0.570 ) . Hemoglobin loss was higher in the placebo group . Transfusion rates was lower in TA group ( 5.6 % ) compared to the placebo group ( 30 % ) ( P=0.06 ) . No significant difference in The Allowable Blood Loss during the surgery was found between the two groups ( P=0.894 ) . CONCLUSION Preoperative treatment with TA  reduces postoperative blood loss and the need for blood transfusion during traumatic femoral fracture operation Background : Extensive blood loss is common in pediatric craniosynostosis reconstruction surgery .  Tranexamic acid ( TXA ) is increasingly used to reduce perioperative blood loss in various setting s , but data on its efficacy are limited in children . The purpose of this r and omized , double-blind , placebo-controlled , parallel trial was to evaluate the efficacy of TXA in pediatric craniosynostosis correction surgery . The primary and secondary outcome variables were reduction in perioperative blood loss and reduction in blood transfusion , respectively . Methods : Forty-three children , ages 2 months to 6 yr , received either placebo or TXA in a loading dose of 50 mg·kg−1 , followed by an infusion of 5 mg·kg−1·h−1 during surgery . TXA plasma concentrations were measured . Results : The TXA group had significantly lower perioperative mean blood loss ( 65 vs. 119 ml·kg−1 , P < 0.001 ) and lower perioperative mean blood transfusion ( 33 vs. 56 ml · kg−1 , P = 0.006 ) compared to the placebo group . The mean difference between the TXA and placebo groups for total blood loss was 54 ml·kg−1 ( 95 % CI for the difference , 23–84 ml·kg−1 ) and for packed erythrocytes transfused was 23 ml·kg−1 ( 95 % CI for the difference , 7–39 ml·kg−1 ) . TXA administration also significantly diminished ( by two thirds ) the perioperative exposure of patients to transfused blood ( median , 1 unit vs. 3 units ; P < 0.001  ) . TXA plasma concentrations were maintained above the in vitro thresholds reported for inhibition of fibrinolysis ( 10 & mgr;g·ml−1 ) and plasmin-induced platelet activation ( 16 & mgr;g·ml−1 ) throughout the infusion . Conclusions : TXA is effective in reducing perioperative blood loss and transfusion requirement in children undergoing craniosynostosis reconstruction surgery A best evidence topic in cardiac surgery was written according to a structured protocol . The question addressed was whether prophylactic tranexamic acid can safely reduce bleeding without increasing thrombotic complications in patients undergoing cardiac surgery . Altogether 334 papers were found using the reported search , of which 12 represented the best evidence on this topic . The author , journal , date and country of publication , patient group studied , study type , relevant outcomes , results , and study weaknesses were tabulated . We conclude that tranexamic acid clearly reduces blood loss , requirement for blood transfusion , and the risk of reoperation for bleeding , and although no study has yet looked directly at vein graft patency with tranexamic acid , no r and omized studies have raised concerns over its safety AIMS We chose unstable extra-capsular hip fractures as our study group because these types of fractures suffer the largest blood loss . We hypothesised that tranexamic acid ( TXA ) would reduce total blood loss ( TBL ) in extra-capsular fractures of the hip . PATIENTS AND METHODS A single-centre  placebo-controlled double-blinded r and omised clinical trial was performed to test the hypothesis on patients undergoing surgery for extra-capsular hip fractures . For reasons outside the control of the investigators , the trial was stopped before reaching the 120 included patients as planned in the protocol . RESULTS In all 72 patients ( 51 women , 21 men ; 33 patients in the TXA group , 39 in the placebo group ) were included in the final analysis , with a significant mean reduction of 570.8 ml ( p = 0.029 ) in TBL from 2100.4 ml ( st and ard deviation ( sd ) = 1152.6 ) in the placebo group to 1529.6 ml ( sd = 1012.7 ) in the TXA group . The 90-day mortality was 27.2 % ( n = 9 ) in the TXA group and 10.2 % ( n = 4 ) in the placebo group ( p = 0.07 ) . We were not able to ascertain a reliable cause of death in these patients . DISCUSSION TXA significantly reduced TBL in extra-capsular hip fractures , but concerns 
    Output:
    
Conclusion : There is evidence that TXA reduces the proportion of patients requiring blood transfusions when undergoing hip fracture surgery .