***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: Purpose . To compare the use of a blood salvage and reinfusion system with st and ard allogeneic blood transfusion  after total knee arthroplasty — a procedure associated with significant postoperative blood loss . Methods . Between June 2002 and May 2004 , 60 patients undergoing total knee arthroplasty were r and omly allocated into a reinfusion group ( n=26 ) or a control group ( n=34 ) . Patients in the reinfusion group had their blood reinfused from drains within 6 hours of surgery . Both groups received allogeneic blood transfusions according to specified transfusion criteria if the haemoglobin level fell below 90 g/l , or in the presence of severe anaemic symptoms . Haemoglobin levels and drain output were recorded daily for 3 consecutive days after surgery . Results . There was no significant difference between the 2 groups in demographic data , drain output , total blood loss , and mean postoperative haemoglobin levels . Significantly more allogeneic blood was required by the control group than by the reinfusion group ( p=0.022 ) . Conclusion . Postoperative reinfusion of drained blood reduced the need for blood transfusion after total knee arthroplasty , while having an effect on postoperative haemoglobin level equivalent to st and ard allogeneic blood transfusion To investigate the safety and efficacy of  postoperative autologous blood transfusion ( AT ) using the Shiley hardshell venous reservoir , a prospect i ve , r and omised , controlled study was carried out in two matched groups of twenty patients undergoing elective coronary artery bypass surgery .  The mean volume of shed mediastinal blood reinfused in the first 6 h postoperatively was 371.7 + /- 63.23 ml . Use of homologous blood  was reduced from 760.5 + /- 108.37 ml in the control patients to 466.25 + /- 87.44 ml in the AT patients , a reduction of 38.7 % ( p less than 0.05 ) . There was no statistically significant difference in the clinical outcome , overall blood loss , use of platelets , fresh frozen plasma and colloids , haematological indices , renal and hepatic functions , or clotting mechanism , although there was a reduction in the fibrinogen level in the patients who received AT ( p less than 0.05 ) . Mediastinal blood did not clot and was defibrinogenated . It contained significant levels of haemoglobin ( 8.175 + /- 0.506 g/dl ) , platelets ( 96.55 + /- 10.39 per mm3 10(3 ) ) , protein ( 42.5 + /- 1.13 g/l ) , calcium ( 2.385 + /- 0.054 mmol/l ) and was well oxygenated ( PO2 = 20.46 + /- 0.81 kPa ) . No patients developed bacteraemia or had any AT-related infections . We conclude that postoperative autologous transfusion using the Shiley hardshell venous reservoir is a safe and efficient method for reducing postoperative homologous blood requirement after coronary artery bypass surgery A series of 40 patients undergoing primary unilateral total knee arthroplasty were entered into a r and omised controlled trial to assess the safety and efficacy of postoperative autologous blood salvage and reinfusion . The mean volume of autologous blood reinfused was 520 ml per patient ( 51 % of the mean total drainage ) .  Homologous blood transfusion  was required in only 35 % of patients in the study group compared with 95 % of patients in the control group ( P less than 0.001 ) . The mean volume of homologous blood transfused was 0.9 units per patient in the study group compared with 2.5 units in the control group ( P less than 0.001 ) , a saving of 64 % BACKGROUND Aprotinin therapy is now widely used during cardiac surgery . This study examined the clinical and economic effectiveness of high-dose or low-dose aprotinin in comparison to placebo . METHODS In a double blind , r and omized study , three groups of 50 patients received  high-dose aprotinin costing AUS$614 per patient ( AUS$ = Australian dollars ) , low-dose aprotinin costing AUS$220 per patient or placebo .  Re source use influenced by aprotinin therapy was measured . RESULTS Both doses were effective in reducing chest drainage and postoperative transfusion requirements , high-dose being more effective than low-dose . Both doses reduced the rate of reoperations for hemostasis . A base case of statistically significant differences associated with the high-dose and low-dose aprotinin showed cost savings of AUS$77 and AUS$348 per patient , respectively . If the demonstrated less significant reductions in operating room and ward stay are included , these savings become AUS$463 and AUS$715 , respectively . Alternately , if cross-matches are replaced by group- and -hold and cell savers are not used , the savings per patient would be AUS$196 and AUS$467 , respectively . CONCLUSIONS While high-dose aprotinin is clinical ly more effective than low-dose aprotinin , low-dose therapy demonstrates greater cost savings BACKGROUND : Previous trials have indicated that cell salvage may reduce allogeneic blood transfusion during cardiac surgery , but these studies have limitations , including inconsistent use of other blood transfusion-sparing strategies . We design ed a r and omized controlled trial to determine whether routine cell salvage for elective uncomplicated cardiac surgery reduces blood transfusion and is cost effective in the setting of a rigorous transfusion protocol and routine administration of antifibrinolytics . METHODS : Two-hundred-thirteen patients presenting for first-time coronary artery bypass grafting and /or cardiac valve surgery were prospect ively r and omized to control or cell salvage groups . The latter group had blood aspirate during surgery and mediastinal drainage the first 6 h after surgery processed in a cell saver device and autotransfused . All patients received tranexamic acid and were subjected to an algorithm for red blood cell and hemostatic blood factor transfusion . RESULTS : There was no difference between the two groups in the proportion of patients exposed to allogeneic blood ( 32 % in both groups , relative risk 1.0 P = 0.89 ) . At current blood products and cell saver prices , the use of cell salvage increased the costs per patient by a minimum of $ 103 . When patients who had mediastinal re-exploration for bleeding were excluded ( as planned in the protocol ) , significantly fewer units of allogeneic red blood cells were transfused in the cell salvage compared with the control group ( 65 vs 100 U , relative risk 0.71 P = 0.04 ) . CONCLUSION : In patients undergoing routine first-time cardiac surgery in an institution with a rigorous blood conservation program , the routine use of cell salvage does not further reduce the proportion of patients exposed to allogeneic blood transfusion . However , patients who do not have excessive bleeding after surgery receive significantly fewer units of blood with cell salvage . Although the use of cell savage may reduce the dem and for blood products during cardiac surgery , this comes at an increased cost to the institution To evaluate the safety and effectiveness of the collection and retransfusion of postoperatively shed mediastinal blood as part of a multifaceted approach to blood conservation following cardiac operation , 113 patients were r and omized into either an  autotransfusion group ( 54 patients ) or a control group ( 59 patients ) . Intraoperative and postoperative hemodilution was practice d in all patients . The clinical safety of this technique was confirmed by the lack of septic , hematological , pulmonary , renal , or hepatic complications . However , in this setting where blood conservation is already aggressively practice d , the ability of the technique to further reduce the use of banked blood following cardiac surgical procedures was not demonstrated A controlled , r and omised , prospect i ve study was undertaken to assess the efficacy of the use of a blood re-infusion device in the reduction of allogenic blood requirements of patients undergoing bilateral simultaneous total knee replacements . Thirty-three consecutive patients were  r and omised to receive allogenic blood only , or a combination of collected and re-infused blood . An average of 1000 ml of drainage blood was salvaged in the study group , result ing in a significant reduction in allogenic blood requirements from 6.3 to 3.8 units in total ( P value=0.002 ) . No patients suffered transfusion reactions . We conclude that autologous re-infusion is a safe and effective method of reducing allogenic blood requirements , and as a result , reducing the risks of transmission of infection , and the rate of post-operative infection BACKGROUND Autotransfusion of shed mediastinal blood may reduce the need for homologous blood transfusions in cardiac surgery . In an earlier study we have shown that the red blood cells ( RBCs ) of shed mediastinal blood have a normal membrane stability ( osmotic fragility ) compared with circulating RBCs after coronary artery bypass grafting and better than stored RBCs . This indicates that RBCs in shed mediastinal blood are not damaged further during salvage . It remains to be determined how autotransfusion affects the survival of RBCs from shed mediastinal blood . METHODS We performed a prospect i ve , r and omized , and controlled study involving 26 patients having elective , uncomplicated coronary artery bypass grafting . Dual-isotope labeling technique ( chromium 51 and technetium 99 m ) was used to investigate the 24-hour survival of RBCs from shed mediastinal blood and RBCs from circulating blood , and to estimate the mean survival time of RBCs . RESULTS There was no significant difference between the 24-hour survival of shed mediastinal RBCs and circulating RBCs . The estimated mean cell lifespan was 20.5 days ( range , 11.6 to 29.0 days ) for shed mediastinal RBCs and 22.7 days ( range , 14.4 to 36.2 days ) for circulating RBCs . CONCLUSIONS The survival of RBCs from shed mediastinal blood after autotransfusion is comparable with the survival of RBCs in the patients ' circulating blood PURPOSE The net benefit of routine intraoperative autotransfusion ( IAT ) in patients undergoing elective infrarenal aortic surgery was studied . METHODS One hundred patients undergoing abdominal aortic aneurysm ( AAA ) repair ( n = 50 ) or aortofemoral bypass ( AFB ) for occlusive disease ( n = 50 ) were r and omized to IAT and control groups .  This experience accounted for 58 % of patients undergoing aortic surgery during the 16-month study period . RESULTS IAT and control groups were balanced for preoperative demographics , disease ( 50:50 split of AFB : AAA in each group ) , and risk factors . There were no significant differences between patients r and omized to IAT and control patients in estimated blood loss ( EBL ) , allogeneic blood transfusion ( units administered intraoperatively , postoperatively , and total ) , proportion of patients not receiving allogeneic blood ( 34 % of patients r and omized to IAT and 28 % of control patients ) , postoperative hemoglobin/hematocrit levels , and complications .  IAT did not reduce allogeneic blood transfusion among all patients undergoing aortic surgery nor in any subgroups that might be more likely to benefit , such as those undergoing AAA repair , those with 1000 mL or more EBL , and those receiving larger volumes of IAT-processed blood . CONCLUSION We could find no net benefit of IAT in patients undergoing elective , infrarenal aortic surgery The purpose of the study reported here was the determination of the efficacy of a postoperative autologous blood drainage and transfusion device in reducing allogeneic red cell requirements in patients undergoing elective knee arthroplasty . The study was a r and omized controlled trial with adult patients undergoing unilateral elective arthroplastic knee surgery . Patients underwent suction drainage , attached to an autologous blood drainage and transfusion device , or st and ard suction drainage . Allogeneic red cells were given according to strict transfusion guidelines based on blood loss and postoperative hemoglobin values . Outcome measures included the mean number of allogeneic red cell concentrates required and the number of patients in each group who required no transfusion . Patients assigned to st and ard suction drainage had a mean allogeneic red cell utilization of 1.2 units ( SD 1.0 ) , as compared to a mean of 0.4 units ( SD 0.8 ) in the group undergoing drainage with the autologous blood drainage and transfusion device ( p = 0.0007 ) . The percentage of patients not requiring allogeneic red cells was significantly higher in the latter group ( 74.3 % vs. 32.5 % ; p = 0.002 ) . The postoperative drainage and transfusion device was efficacious in reducing the amount of allogeneic red cells required by patients undergoing knee arthroplasty , and its use result ed in a 42 percent reduction in the number of patients requiring allogeneic transfusion BACKGROUND The aim of this study was to ascertain whether cell salvage and autotransfusion after first time elective coronary artery bypass grafting is associated with a significant reduction in the use of homologous blood , a clinical ly significant derangement of postoperative clotting profiles , or an increased risk of 
    Output:
    
Cell salvage did not appear to impact adversely on clinical outcomes .
The results suggest cell salvage is efficacious in reducing the need for allogeneic red cell transfusion in adult elective cardiac and orthopaedic surgery .
The use of cell salvage did not appear to impact adversely on clinical outcomes .
As the trials were unblinded and lacked adequate concealment of treatment allocation , transfusion practice s may have been influenced by knowledge of the patients ' treatment status potentially biasing the results in favour of cell salvage