***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 Aprotinin and epsilon aminocaproic acid are antifibrinolytic agents used to reduce postoperative blood loss after cardiopulmonary bypass . We compared low dose aprotinin with epsilon aminocaproic acid and a combination of the two agents to reduce postoperative blood loss in infants with congenital cyanotic heart disease undergoing corrective surgical procedures . METHODS This prospect i ve study was conducted r and omly on 300 children . Group I ( n = 80 ) acted as the control and did not receive either of the study drugs . Group II ( n = 100 ) received low dose aprotinin , group III ( n = 60 ) received epsilon aminocaproic acid , and group IV ( n = 60 ) received a combination of the two antifibrinolytic agents . RESULTS The control group had the longest time for sternal closure , maximum blood loss at 24 hours , and greatest requirements for packed red blood cells and platelets . Fibrinogen levels were significantly lower , and levels of fibrin breakdown products were significantly higher compared with the groups given either or both of the antifibrinolytics . CONCLUSIONS Epsilon aminocaproic acid is as efficacious as low dose aprotinin in reducing postoperative blood loss and packed red blood cell and platelet requirements in children with congenital cyanotic heart disease . The combination of the two was slightly more effective To evaluate the functional integrity of platelets in patients administered the proteinase inhibitor aprotinin during cardiopulmonary bypass , 20 patients undergoing a complicated and prolonged open heart operation were studied . They were r and omized to receive either a high dose of aprotinin ( total dose , 6 to 7 x 10(6 ) KIU ) before and during cardiopulmonary bypass ( 10 patients ) or a placebo ( 10 patients ) . Blood sample s were collected preoperatively , at the termination of bypass , and 90 minutes thereafter to assess platelet count and aggregation on extracellular matrix , which was studied by scanning electron microscopy . On a scale of 1 to 4 , mean preoperative platelet aggregation grade s were similar in both groups ( 3.5 + /- 0.5 ) . Postoperatively , at the termination of cardiopulmonary bypass and 90 minutes thereafter , all 10 patients treated with aprotinin revealed normal , unchanged platelet aggregation ( grade , 3.5 + /- 0.5 ) , whereas all placebo-treated patients showed severely disturbed aggregation ( grade , 1.4 + /- 0.5 ) ( p less than 0.001 ) . The platelet count was similar in both groups before and after operation ( preoperatively , 182 + /- 75 x 10(9)/L and 146 + /- 30 x 10(9)/L , and postoperatively , 87 + /- 13 x 10(9)/L and 80 + /- 27 x 10(9)/L for the aprotinin and placebo groups , respectively ) . Total 24-hour postoperative bleeding and blood requirement were significantly lower in the aprotinin group ( 371 + /- 84 mL and 2 + /- 0.7 units , respectively ) compared with the placebo group ( 608 + /- 28 mL and 3.4 + /- 1.3 units , respectively ) ( p less than 0.01 ) . These results demonstrate that improved postoperative hemostasis is directly related to the complete preservation of platelet function achieved by the protective properties of aprotinin Excessive hemorrhage secondary to cardiopulmonary bypass may be encountered after pediatric cardiac operations . Platelet dysfunction appears to be especially responsible for this problem . The proteinase inhibitor aprotinin is suggested to possess platelet preservation properties and reduce blood loss in this situation . The effects of aprotinin ( 25,000 U/kg after induction of anesthesia , 25,000 U/kg added to the prime , 25,000 U/kg every hour of cardiopulmonary bypass ) on platelet function were r and omly studied in 12 children with a weight of less than 10 kg ( group 2 ) and 12 children weighing more than 10 kg ( group 4 ) , who were compared with two groups of children without aprotinin ( group 1 , < 10 kg ; group 3 , > 10 kg ) . Twelve children undergoing major vessel operations without cardiopulmonary bypass and aprotinin  served as a control .  Platelet function was assessed using aggregometry ( turbidometric technique with adenosine diphosphate , 2.0 mumol/L ; collagen , 4 micrograms/mL ; epinephrine , 25 mumol/L ; NaCl [ control ] ) . Platelet function was not altered in the control patients within the entire investigation period . Maximum aggregation in the small children was already lower at baseline in comparison with that of the children > 10 kg . Cardiopulmonary bypass was followed by a significant reduction in platelet aggregation in all groups . Treatment with aprotinin did not improve platelet function ( maximum aggregation and maximum gradient of aggregation ) in any group . On the first postoperative day , maximum aggregation in the small children exceeded baseline values , whereas in both groups of children > 10 kg baseline values had almost been established . Postoperative blood loss was not reduced by treatment with aprotinin . ( ABSTRACT TRUNCATED AT 250 WORDS The effect of the proteinase-inhibitor aprotinin on blood loss and homologous blood requirement in cardiac surgery was investigated . In a prospect i ve study , 902 adult patients were treated with high-dose aprotinin ( total greater than 5 x 10(6 ) kallikrein inactivator units [ KIU ] ; group A ) , while 882 patients without aprotinin administration served as the controls  ( group C ) . Both groups were operated on between January 1987 and October 1989 , and included patients with primary coronary artery bypass grafting ( n = 525 group C , n = 560 group A ) , valve replacement ( n = 292 group C , n = 264 group A ) , or combined procedures ( n = 65 group C , n = 78 group A ) , as well as cardiac reoperations ( n = 91 group C , n = 110 group A ) . The average blood loss 36 hours postoperatively in the aprotinin group was 679 + /- 419 mL , compared with 1,038 + /- 671 mL in the control group ( P less than 0.05 ) . Total homologous blood requirement was also significantly less in group A ( 942 + /- 1,630 mL ) compared with group C ( 1,999 + /- 2,283 mL ) ( P less than 0.05 ) , a reduction of 53 % . Serum creatinine concentrations did not show intergroup differences on the first postoperative day ( group A , 1.2 + /- 0.7 ; group C , 1.3 + /- 0.5 mg/dL ) or on discharge from the intensive care unit ( ICU ) . Thus , impairment of renal function as a consequence of aprotinin treatment was not observed . Three patients developed signs of mild circulatory depression after injection of aprotinin , which responded promptly to vasopressor therapy . ( ABSTRACT TRUNCATED AT 250 WORDS We performed a prospect i ve , r and omized , placebo-controlled , double-blind trial to assess the efficacy of aprotinin in 61 children ( median age 3.7 yr ) undergoing reoperative open heart surgery ( OHS ) . Three demographically similar groups were studied : large-dose aprotinin ( ALD ) , small-dose aprotinin ( ASD ) , and placebo ( P ) . Over the first 24 postoperative hours fewer patients in the aprotinin groups received packed red cells ( ALD , 53 % ; ASD , 89 % ; and P , 95 % ; P = 0.001 ) , platelets ( ALD , 32 % ; ASD , 50 % ; and P , 65 % ; P = 0.04 ) , and fresh frozen plasma ( ALD , 16 % ; ASD , 17 % ; and P , 60 % ; P = 0.003 ) than placebo patients . Most importantly , aprotinin patients had fewer exposures to banked blood components ( ALD , median 1 U ; and ASD , median 2 U ) than P ( median 6 U ; P = 0.001 ) , with no difference in overall complication rate . Use of aprotinin was associated with a savings in the patient charges for blood components , operating room time , and duration of hospitalization . In conclusion , aprotinin decreased the number of units of banked blood components used during the first 24 postoperative hours in reoperative pediatric OHS . Aprotinin thus decreases the risks associated with exposure to banked blood components and reduces hospital charges . ( Anesth Analg 1996;83:1193 - 9 BACKGROUND Though multiple studies have affirmed the effectiveness of aprotinin in reducing blood loss in adult cardiac surgery , the possible benefit in pediatric cardiac surgery is controversial . METHODS In a double-blind , r and omized , and placebo-controlled study , the efficacy of aprotinin in attenuating the hemostatic and inflammatory activation during cardiopulmonary bypass in 60 patients weighing less than 10 kg was investigated . Secondary endpoints were the influence of aprotinin  on the reduction of blood loss and allogeneic blood requirement , as well as postoperative oxygenation and length of mechanical ventilation .  Aprotinin was administered in a high-dose of 3 x 10(4 ) KIU/kg plus a bolus of 5 x 10(5 ) KIU ( not weight adjusted ) added to the pump prime . RESULTS  Aprotinin plasma concentration at the end of cardiopulmonary bypass ( CPB ) was with 184 + /- 45 KIU/mL , within the targeted range of 200 KIU/mL. Coagulation and fibrinolysis were suppressed ( F1.2 1 hour after CPB : 5.35 + /- 2.9 nmol/L vs 14.5 + /- 23.1 nmol/L ; D-dimer 1 hour after CPB : 0.63 + /- 0.6 ng/mL vs 2.3 + /- 3.1 ng/mL ; p < 0.05 ) , inflammatory markers ( interleukin [IL]-6 , IL-8 , IL-10 ) increased over time without significant differences between the groups , and only complement C3a activation was significantly attenuated at the end of CPB in the aprotinin group . Chest tube drainage was significantly reduced ( 24 hours : median 13.5 [ IQR 12.2 ] mL/kg vs 19.4 [ 8.2 ] mL/kg ; p < 0.05 ) . All patients received one unit of packed cells to prime the heart lung machine . A second unit was needed significantly less often in the aprotinin group ( 13 % vs 47 % ; p < 0.05 ) . Postoperative oxygenation ( pO2/FIO2 172 [ IQR 128 ] mm Hg vs 127 [ 74 ] ; p < 0.05 ) improved , and the time on ventilator was shorter in the aprotinin group ( median 45 hours [ IQR 94 ] vs 101 [ IQR 74 ] ; p < 0.05 ) . No side effects were attributable to the use of aprotinin . CONCLUSIONS High-dose aprotinin effectively attenuated hemostatic activation and reduced blood loss and transfusion requirement in pediatric cardiac surgery . Postoperative ventilation was also shortened in the aprotinin group Thirty children undergoing surgical repair for congenital heart defects were r and omly selected for a double-blind study on the anti-hemorrhagic and blood-saving properties of aprotinin . The treatment group comprised 14 patients who received aprotinin 7 mg/kg of body weight until the end of perfusion . The placebo group ( n = 16 ) received an infusion of the corresponding volumes of saline . Patients treated with aprotinin  bled less during the operation ( 12.6 ml/kg versus 18.1 ml/kg , p = 0.25 ) and in the first 24 postoperative hours ( chest drainage 12.1 ml/kg versus 17.7 ml/kg , p = 0.07 ) . Hemoglobin loss into chest drainage was reduced in the treated group by half ( 0.66 versus 1.21 gm in 24 hours , p = 0.07 ) . Fewer blood donors were needed during hospitalization by patients receiving aprotinin ( 1.07 versus 2.75 donors per patient , p = 0.04 ) . Postoperative transfusion was unnecessary in 64.2 % of patients receiving aprotinin compared with only 25 % of the placebo group ( p = 0.03 ) . Aprotinin increased diuresis significantly during perfusion ( 4.3 ml/kg versus 1.0 ml/kg , p = 0.005 ) . Other parameters are evaluated , and considerations are made regarding adequacy of the dosage regimen . The drug seems to be safe and easy to h and le in children BACKGROUND Conflicting reports exist in the medical literature regarding the association between industry funding and published research findings . In 
    Output:
    
Aprotinin did not have a significant effect on the volume of blood transfused or on the amount of postoperative chest tube drainage .
Overall , aprotinin reduced the proportion of children who received blood transfusion during cardiac surgery with cardiopulmonary bypass .