***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 Some observational studies suggest that the use of pulmonary-artery catheters to guide therapy is associated with increased mortality . METHODS We performed a r and omized trial comparing goal -directed therapy guided by a pulmonary-artery catheter with st and ard care without the use of a pulmonary-artery catheter . The subjects were high-risk patients 60 years of age or older , with American Society of Anesthesiologists ( ASA ) class III or IV risk , who were scheduled for urgent or elective major surgery , followed by a stay in an intensive care unit . Outcomes were adjudicated by observers who were unaware of the treatment-group assignments . The primary outcome was in-hospital mortality from any cause . RESULTS Of 3803 eligible patients , 1994 ( 52.4 percent ) underwent r and omization . The base-line characteristics of the two treatment groups were similar . A total of 77 of 997 patients who underwent surgery without the use of a  pulmonary-artery catheter ( 7.7 percent ) died in the hospital , as compared with 78 of 997 patients in whom a pulmonary-artery catheter was used ( 7.8 percent)--a difference of 0.1 percentage point ( 95 percent confidence interval , -2.3 to 2.5 ) . There was a higher rate of pulmonary embolism in the catheter group than in the st and ard-care group ( 8 events vs. 0 events , P=0.004 ) . The survival rates at 6 months among patients in the st and ard-care and catheter groups were 88.1 and 87.4 percent , respectively ( difference , -0.7 percentage point [ 95 percent confidence interval , -3.6 to 2.2 ] ; negative survival differences favor st and ard care ) ; at 12 months , the rates were 83.9 and 83.0 percent , respectively ( difference , -0.9 percentage point [ 95 percent confidence interval , -4.3 to 2.4 ] ) . The median hospital stay was 10 days in each group . CONCLUSIONS We found no benefit to therapy directed by pulmonary-artery catheter over st and ard care in elderly , high-risk surgical patients requiring intensive care Introduction Several studies have shown that goal -directed hemodynamic and fluid optimization may result in improved outcome . However , the methods used were either invasive or had other limitations . The aim of this study was to perform intraoperative goal -directed therapy with a minimally invasive , easy to use device ( FloTrac/Vigileo ) , and to evaluate possible improvements in patient outcome determined by the duration of hospital stay and the incidence of complications compared to a st and ard management protocol . Methods In this r and omized , controlled trial 60 high-risk patients scheduled for major abdominal surgery were included . Patients were allocated into either an enhanced hemodynamic monitoring group using a cardiac index based intraoperative optimization protocol ( FloTrac/Vigileo device , GDT-group , n = 30 ) or a st and ard management group ( Control-group , n = 30 ) , based on st and ard monitoring data . Results The median duration of hospital stay was significantly reduced in the GDT-group with 15 ( 12 - 17.75 ) days versus 19 ( 14 - 23.5 ) days ( P = 0.006 ) and fewer patients developed complications than in the Control-group [ 6 patients ( 20 % ) versus 15 patients ( 50 % ) , P = 0.03 ] . The total number of complications was reduced in the GDT-group ( 17 versus 49 complications , P = 0.001 ) . Conclusions In high-risk patients undergoing major abdominal surgery , implementation of an intraoperative goal -directed hemodynamic optimization protocol using the FloTrac/Vigileo device was associated with a reduced length of hospital stay and a lower incidence of complications compared to a st and ard management protocol .Trial Registration Clinical trial registration information : Unique identifier : Background : An individualized fluid optimization strategy , based on maximization of cardiac stroke volume ( SV ) with colloid boluses ( goal ‐directed therapy ) , improves outcome after surgery .  Oesophageal Doppler ( OD ) is used for SV maximization in most r and omized studies , but evidence ‐based guidelines for the SV maximization procedure are lacking and variation in SV may influence the indication for fluid administration . We measured beat‐to‐beat OD SV before and after  fluid optimization  in order to estimate the number of heartbeats for which SV needs to be averaged to provide an acceptable accuracy for goal ‐directed therapy with this technology OBJECTIVE To evaluate the effects of increased oxygen delivery on mortality and morbidity . DESIGN R and omized , controlled trial . SETTING Medical-surgical ICU of a tertiary care hospital . PATIENTS Sixty-three patients classified according to predetermined criteria as having severe sepsis or septic shock . INTERVENTIONS The patients were r and omly assigned to one of two groups : the control group ( n = 32 ) received conventional therapy with a normal targeted value of oxygen delivery , and the treatment group ( n = 31 ) received therapy with a targeted oxygen delivery index ( DO2I ) value of > 600 mL/min/m2 . The therapeutic approach to maintain BP , arterial saturation , hemoglobin concentration , and pulmonary artery occlusion pressure was similar in both groups . MEASUREMENTS AND MAIN RESULTS The hemodynamic , oxygen transport , and gastric intramucosal pH measurements were recorded at the time of admission to the study and every 6 h for the next 96 h. The outcome measures were the rate of patient mortality and the number of organ dysfunctions occurring during the ICU stay . The study groups were similar with respect to demographics and admission hemodynamic variables , but the percentage of patients with positive blood cultures was significantly higher in the control group than in the treatment group , respectively : 34 vs 13 % ( p = 0.04 ) . The average cardiac index was significantly higher in the treatment group than in the control group , respectively : 3.96 vs 3.05 L/min/m2 ( p = 0.01 ) . This factor did not significantly affect the DO2I . Nine of the 31 treatment group patients reached an average DO2I value of > 600 mL/min/m2 . The rate of mortality in the control group patients up to the time of ICU discharge ( 66 % ) was similar to that seen in the treatment group ( 74 % ) , respectively : 21 of 32 vs 23 of 31 ( p = 0.46 ) . The number of dysfunctional organs per patient was also similar in the control and treatment groups , respectively : 2.1+/-1.1 vs 2.6+/-1.2 ( p = 0.12 ) . CONCLUSION Treatment aim ed at maximizing oxygen delivery in patients with severe sepsis or septic shock does not reduce mortality or morbidity BACKGROUND A prospect i ve , r and omized controlled trial comparing conventional intraoperative fluid management with two differing methods of invasive haemodynamic monitoring to optimize intraoperative fluid therapy , in patients undergoing proximal femoral fracture repair under general anaesthesia . METHODS Ninety patients r and omized to three groups ; conventional intraoperative fluid management ( Gp CON  , n=29 ) , and two groups receiving additional repeated colloid fluid challenges guided by central venous pressure ( Gp CVP , n=31 ) or oesophageal Doppler ultrasonography ( Gp DOP , n=30 ) . Primary outcome measures were time to medical fitness to discharge , hospital stay and postoperative morbidity . RESULTS The fluid challenge result ed in significantly greater perioperative changes in central venous pressure between Gp CVP and Gp CON ( mean 5 ( 95 % confidence interval 3 - 7 ) mm Hg ) ( P<0.0001 ) . Important perioperative changes were also shown in Gp DOP with increases of 49.4 ms ( 19.7 - 79.1 ms ) in the corrected flow time , 13.5 ml ( 7.4 - 19.6 ml ) in stroke volume , and 0.9 ( 0.49 - 1.39 ) litre min(-1 ) in cardiac output . As a result , fewer patients in Gp CVP and Gp DOP experienced severe intraoperative hypotension ( Gp CON 28 % ( 8/29 ) , Gp CVP 9 % ( 3/31 ) , Gp DOP 7 % ( 2/30 ) , P=0.048 ( chi-squared , 2 degrees of freedom ( df ) . No differences were seen between the three groups when major morbidity and mortality were combined , P=0.24 ( chi-squared , 2 df ) . Postoperative recovery for survivors , as defined by time to be deemed medically fit for discharge , was significantly faster , in comparison with Gp CON , in both the Gp CVP ( 10 vs 14 ( 95 % confidence interval 8 - 12 vs 12 - 17 ) days , P=0.008 ( t-test ) ) , and Gp DOP ( 8 vs 14 ( 95 % confidence interval 6 - 12 vs 12 - 17 ) days , P=0.023 ( t-test ) . There were no significant differences between groups , for survivors , with respect to acute orthopaedic hospital and total hospital stay . CONCLUSIONS Invasive intraoperative haemodynamic monitoring with fluid challenges during repair of femoral fracture under general anaesthetic shortens time to being medically fit for discharge This systematic review and meta- analysis summarizes the clinical effects of increasing perioperative blood flow using fluids with or without inotropes/vasoactive drugs to explicit defined goals in adults . We included r and omized controlled trials of adult patients ( aged 16 years or older ) undergoing surgery . We included 31 studies of 5292 participants . There was no difference in mortality at the longest follow-up : 282/2615 ( 10.8 % ) died in the control group and 238/2677 ( 8.9 % ) in the treatment group , RR of 0.89 ( 95 % CI : 0.76 - 1.05 ; P=0.18 ) . However , the results were sensitive to analytical methods and withdrawal of studies with method ological limitations . The intervention reduced the rate of three morbidities ( renal failure , respiratory failure , and wound infections ) but not the rates of arrhythmia , myocardial infa rct ion , congestive cardiac failure , venous thrombosis , and other types of infections . The number of patients with complications was also reduced by the intervention . Hospital length of stay was reduced in the treatment group by 1.16 days . There was no difference in critical care length of stay . The primary analysis of this review showed no difference between groups but this result was sensitive to the method of analysis , withdrawal of studies with method ological limitations , and was dominated by a single large study . Patients receiving this intervention stayed in hospital 1 day less with fewer complications . It is unlikely that the intervention causes harm . The balance of current evidence does not support widespread implementation of this approach to reduce mortality but does suggest that complications and duration of hospital stay are reduced Introduction Total hip replacement is one of the most commonly performed major orthopaedic operations . Goal -directed therapy ( GDT ) using haemodynamic monitoring has previously demonstrated outcome benefits in high-risk surgical patients under general anaesthesia .  GDT has never been formally assessed during regional anaesthesia . Methods Patients undergoing total hip replacement while under regional anaesthesia were r and omised to either the control group ( CTRL ) or the protocol group ( GDT ) . Patients in the GDT group , in addition to st and ard monitoring , were connected to the FloTrac sensor/Vigileo monitor haemodynamic monitoring system , and a GDT protocol was used to maximise the stroke volume and target the oxygen delivery index to > 600 mL/minute/m2 . Results Patients r and omised to the GDT group were given a greater volume of intravenous fluids during the intraoperative period ( means ± st and ard deviation ( SD ) : 6,032 ± 1,388 mL vs. 2,635 ± 346 mL ; P < 0.0001 ) , and more of the GDT patients received dobutamine ( 0 of 20 CTRL patients vs. 11 of 20 GDT patients ; P < 0.0003 ) . The GDT patients also received more blood transfused during the intraoperative period ( means ± SD : 595 ± 316 mL vs. 0 ± 0 mL ; P < 0.0001 ) , although the CTRL group received greater volumes of blood replacement postoperatively ( CTRL patients 658 ± 68 mL vs. GDT patients 198 ± 292 mL ; P < 0.001 ) . Overall blood consumption ( intraoperatively and postoperatively ) was not different between the two groups . There were an increased number of complications in the CTRL group ( 20 of 20 CTRL patients ( 100 % ) vs. 16 of 20 GDT patients ( 80 % ) ; P = 0.05 ) . These outcomes were predominantly due to a difference in minor complications ( 20 of 20 CTRL patients ( 100 % ) vs. 15 of 20 GDT patients ( 75 % ) ; P = 0.047 ) . Conclusions GDT applied during regional anaesthesia in patients undergoing elective total hip replacement changes intraoperative fluid management and may improve patient outcomes by decreasing postoperative complications . Larger trials are required to confirm our findings .Trial registration S RCT Objective To determine 
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AUTHORS ' CONCLUSIONS It remains uncertain whether increasing blood flow using fluids , with or without inotropes or vasoactive drugs , reduces mortality in adults undergoing surgery .
The balance of current evidence does not support widespread implementation of this approach to reduce mortality but does suggest that complications and duration of hospital stay are reduced